Development Steps:

1. High-Level Rocket Structure: Thrust Range, Vehicle Mass (+-50%)

2. Conservative(High-Thrust) Thruster / Feed System Design + Review

3. Fluid System Assembly, Testing, Calibration. Instrumentation and Control Development. Flight Structure Design Integration

4. Static Fire Testing. Mass Optimization, Simulation Refinement.

5. Flight Vehicle Integration

Thruster + Injector

Priorities: Stable, Conservative Performance and Efficient Manufacturing/Assembly

• Injector: Unlike-Doublet Impinging, LOX-centered

• Chamber: Ablative + Fuel Jetted Wall-Film. 6061 Aluminum Jacket.

• Nozzle: Graphite Throat, 316L Stainless Steel Expansion

Fluid System (Engine "Feed System")

Flight Avionics: Stackable Sub-Module Array

Instrumentation Requirements:

Command/Communications Structure

Control State Structure

Design & Manufacturing

• Target Apogee, Precision: 2500m, +-10%

• Approx. Vehicle Mass: 40kg dry

• Approx. Thrust Level, Burn Time: 1.80kN, 10sec

• Rapid design iteration

• Physics, Analysis-oriented testing

• Efficient Cross-Specialty Collaboration

• Development for Reliability, Robustness

• Expand team technicality, individual learning capability

Specifications

• Dual side dual deployment

• Redundant Altimeters, ejection charges

• Dual-Camera Onboard Monitoring

• GPS real-time telemetry

Requirements

• Drogue Deployment velocity < 50 ft/s

• Main chute deployment velocity < 100 ft/s

• Landing velocity: below 25 ft/s

• Downwind Drift < 1 km

Demonstration Launch 11/2023

MCMC Dispersion Analysis

Fin design discussion:

We designed our fins based on the need of our rocket. Initially, we had fin dimensions that were larger. However, as our rocket design developed we realized that this design was not meeting our apogee and stability needs. Each change would need our fins to be altered which was constant. After our rocket design was set, we began our fin simulations with respect to our motor simulations. We wanted to make sure our fins and motor complimented each other. We did different fin-size simulations for each motor we felt could be used to meet the needs of our rocket. After many fin/motor simulations and utilizing the optimization tool in Open Rocket, we landed on our current fin dimensions.

Fin Semi-span (inches) *

Distance between root cord to tip cord (inches) - Numeric data only

7.4 in

Fin attachment *

Description of the method used for securing the fins to the airframe.

1. Sand areas of connection before applying epoxy. Clean off any fiberglass dust with IPA solution. Spread epoxy(JBweld) all around the bottom of the fin tab and side of fiberglass, so that it is completely coated.

2. Use the fin jigs to place the fins into the fin slots on the booster tube, so that the tabs are touching the motor tube and the aft side of the tab is touching the middle centering ring.

3. Create smooth epoxy fin fillets around each fin. After thoroughly mixing, wear gloves and use your finger to apply a generous amount of epoxy at the seams between the fins and the booster tube.

General Procedure:

1. Roughen surface with 80 grit sandpaper.

2. Clean surface with 50% IPA, 50% water.

3. Cut 3 types of cuts of cloth:

Fin Flutter Analysis *

Please describe the method and results used to determine the not to exceed flutter velocity or the divergence velocity.

We used the flutter boundary location to determine the rocket’s flutter velocity and ensure that our rocket’s velocity never exceeds this flutter velocity. Assuming our maximum altitude, which is the apogee of 10,000 feet, we were able to derive the estimated air temperature and estimated speed of sound. Finally, we were able to apply our fin geometry to calculate the fin flutter velocity, which is 1682.16 ft/s (1146.9 mph). We confirmed this value using the software FinSim, which combines our fin geometry with more specific rocket data to calculate this same value. Since our rocket’s maximum velocity is predicted to be 972 ft/s, we will not exceed flutter velocity.

Vehicle Weight (pounds) *

All vehicle, electronics, and recovery (pounds) - Numeric data only: NOT including motor case, propellant, or payload weight

48.897 lb

Empty motor case/structure (pounds) *

0.503 lb

Propellent weight (pounds) *

11.7 lb

Payload weight (pounds) *

Must be at least 8.8 lbs per IREC Rules (pounds) - Numeric data only

9.5 lb

Liftoff weight (pounds) *

Vehicle weight + propellant weight + motor case/structure + payload weight (pounds) - Numeric data only

70.6 lb

Center of Pressure (inches) *

The location of the center of pressure measured in inches from the tip of the nose cone. Numeric data only.

91.426 in

Center of Gravity (inches) *

The location of the center of gravity measured in inches from the tip of the nose cone. Numeric data only.

79.264 in

Static Margin *

The distance between the CG and the CP at lift-off is divided by the airframe diameter, measured in calibers. 1.5 is the highly recommended minimum

1.97 cal

Couplers & Airframe joints *

Discuss each airframe joint, including couplers, shoulders, and attachment method(s).

Ref. DTEG 8.5 - Airframe joints that implement “coupling tubes” should be designed such that the coupling tube extends no less than one body tube caliber on either side of the joint – measured from the separation plane. The nose cone is epoxied onto the payload tube. Airbrake coupler attached to airbrakes tube with epoxy. Booster tube coupler is attached to the airbrake tube with #6-32 black-oxide alloy steel screws and to the booster tube with epoxy. Av Bay coupler attached to the main parachute tube with epoxy.

#4-40 nylon screws placed between payload tube and Av Bay coupler.

#4-40 nylon screws placed between Av bay tube and main parachute tube.

Rocket construction narrative/ additional information *

Discussing the construction of your rocket including airframe, couplers, interstage couplers, nose cone, fins, fin attachment, composite materials, and identify commercial or SRAD components.

Booster tube assembly:

Recovery Tube Assembly Procedure:

Avionics Bay Assembly

Payload/Nosecone Assembly

GROUND TEST: The following full ground testing procedure was conducted on February 16th, in preparation for a test launch of the vehicle(with a ballast stack no payload) on February 18th.

Section 7: Propulsion System

Propulsion Type *

Solid

COTS - Commercial Off The Shelve

Propulsion Manufacturer *

Aerotech

COTS Motor - Manufacturers Designation

Aerotech M1939 W-P

Motor Letter Classification *

M

Average Thrust (N) *

1,939.0 N - Avg thrust given by thrustcurve.org/motors/AeroTech/M1939W/

Maximum Thrust (N)

2,429.7 N - Max thrust given by thrustcurve.org/motors/AeroTech/M1939W/

Total Impulse of all Motors (Ns) *

10,481.5 Ns - Total Impulse given by thrustcurve.org/motors/AeroTech/M1939W/

10,369 Ns - Total impulse given by RASP simulator file from thrustcurve.org/motors/AeroTech/M1939W/ ** explanation given in propulsion narrative and additional comments.

Motor Burn Time (s) *

Numeric data only (Seconds)

6.52 s - Motor burn time given by Open Rocket

6.2 s - Motor burn time given by thrustcurve.org/motors/AeroTech/M1939W/

Propulsion Narrative

Due to judges comments from our previous reports, we redid our propulsion simulations through OpenRocket. We used the RASP format simulator file from Thrustcurve.org. However, we wanted to preface a discrepancy between this file and the given information on the Thrustcurve site. For our motor, Aerotech M1939-W the written total impulse is given as 10481.5 Ns. However, the total impulse in the RASP file is 10369 Ns. All our simulations were done with this file, therefore using the impulse value of 10369 Ns.

STAR's first generation liquid rocket engine

Sep. 2018 - Sep. 2021, Viability discussion and project proposal

The project originated from "Hot Take," a project proposal that outlined a plan for STAR to explore liquid rocketry.

Sep. 2021 - Feb. 2022, Designing phase

During this phase, the team mainly focused on designing the physical system, as well as manufacturing various parts of the liquid engine, such as the injector and combustion chamber.

Feb. 2022 - Apr. 2022, Integration

Most of the software and electrical development occurred during this phase.

Apr. 16, 2022, Hot-fire Attempt 1

The first attempt did not succeed, but it provided valuable information regarding the flaw in our system.

May 22, 2022, Hot-fire Attempt 2

Successful hot-fire with a burn time of 6 seconds.

• Thruster:

  • Radiatively Cooled (Heat Sink) Combustion Chamber / Nozzle

  • Injector: Coaxial Shear element mixes compressible GOX with ethanol. Dampens pressure instability through 30% Combustion Pressure element flow resistance

  • Thrust Measurement: (Target 30lb thrust)

    • Three S-type load cells, together, measure total thrust force

  • Pressure Measurement:

    • Wheatsone Bridge Diaphram Pressure Transducers measure intense distributed forces

• Feed System:

  • Energy Regulation:

    • Spring-Loaded Regulators and Stainless Steel Ball 2/3-way Valves.

The Experimental Liquid Low Inpulse Engine (ELLIE) is the first time that STAR has attempted to create a bi-propellant rocket engine. Its purpose was to lay the groundwork for a flyable liquid in future iterations.

Flow control

Hot-fire sequence design

The team is required to stay in the bunker during a hot fire, so the engine must be controlled remotely. We chose to use two ESP32s, one of which would send commands (), and the other would report data (DAQ Board). Both devices were constructed as state machines, with COM Board connected to the computer to transmit the data reported by the DAQ Board.

Here is a state machine diagram to visualize the communication:

Code Implementation

Data acquisition and processing

Automation in calibration

A valuable lesson we learned from the previous hot-fire experience is that we cannot rely solely on commercial piping components, such as off-the-shelf valve regulators, to control the engine system accurately. Therefore, the ELLIE team is continuing as a long-term research group, focusing on advanced valve control.

A significant concern has been the droop in the system. It has severely impacted our engine performance, since only a fraction of the GOX flow truly occurred, which resulted in a fuel-rich burn. Here is the visualization of the issues caused by droop, plotted in MATLAB:

PT1 measures the pressure of the combustion chamber downstream, while PT2 measures the pressure of the GOX flow. It appears that the GOX regulator's droop was much higher than what we expected, since we have addressed droop by intentionally setting the regulated pressure higher than the nominal pressure. The result was a low-pressure, low-mass flow burn in the combustion chamber. This conclusion is supported by PT1 data with a high point of about 150 psi, which is 100 psi below the GOX pressure.

The ELLIE team is addressing this issue by designing a self-regulated valve. The valve will be able to adjust the flow rate according to real-time pressure changes to guarantee a desired mass flow rate.

Reasoning for Update

One of the recovery subteam’s slowest steps at launch is connecting wires to the altimeters. The spaces that the wires must be fit into are very small, making it difficult to maneuver and secure them. This can lead to delays because connecting the wires is time-consuming and insecure connections can lead to ground test failure. It also cannot be fully-completed ahead of time as the altimeters must be re-wired between ground test and launch.

Previous solutions have involved positioning the altimeters on the sled such that the connections are easier to access and using crimps to speed up the connection process. However, even with good altimeter placement, it can be difficult to position the wires. Recovery also had issues in creating secure connections to the crimps and did not consider them reliable enough for launch.

New solution

Recovery plans to solder short lengths of wire directly into the altimeters at one end and into a crimp at the other. The end with the crimp could then be easily connected to a longer wire for ground test or flight, saving time at launch. Soldering into the crimp should increase the security of the connection, preventing the previous problems associated with crimps.

This solution allows recovery to change the wiring of the altimeters, despite soldering a wire permanently into the altimeter because the long wire going to the other connection point is replaceable. Solutions involving solder were previously not considered because of the requirement of reconfiguring wires at launch.

Schematic

PinkBeary (SSEP) was launched at FAR on 17 September 2022. The mission of stage separation was successful, but a rapid unscheduled disassembly (RUD) about 1 second after upper stage motor airstart due to improper airframe connection caused a partial mission failure.

The total cost for a 5.5 inch diameter rocket is $680.57.

6 Inch Diameter

The total cost for a 6 inch diameter rocket is $867.05.

Conclusion

We decided that a 5.5 inch diameter rocket would be most beneficial. While this option is not the least expensive, it does allow for future growth. Although a 5.5 inch diameter rocket reaches a lower apogee than a 6 inch rocket and can carry less payload, we decided it is more beneficial for us as a club to understand the process of building and launching a dual stage rocket than it is to overdo our first attempt. A 5.5 inch stage separation rocket is not too risky, but will also allow us to use larger motors and reach higher altitudes in future launches. This rocket will help us gain experience in designing, manufacturing, and launching a dual stage rocket. This will be beneficial overall for the club and our long term goal of achieving a space shot.

See these two documents for our original data and cost comparisons, plus sources and links to purchase the parts.

MINDI achieved an apogee of 14,325ft, which was the highest apogee reached by any UC Berkeley team at the time.

An Overview

Pyro Bolts are an effective way of performing stage separation for in flight vehicles and they can be carried out in a number of ways. Our design prides itself on simplicity, cost effectiveness, and reusability (except for the bolts themselves).

We start with two manufactured O-rings that are each epoxied (or fastened otherwise) to our two airframe tubes, these rings will stay attached throughout the entire launch-recovery process. We then take screws and drill them out, fill them with black powder, insert igniters (e-matches, insert 2 for redundancy), then seal the fasteners. This process is detailed in separate sources and in our stage separation testing documents. The screws can be inserted through holes in the both the O-rings and will be fastened with a wing nut located on the other side of the opposite O-ring. When all screws are ignited, they ideally break and there is no longer anything keeping the two stages together. To ensure separation we opt to place springs between the O-rings, around the screws in order to add force for separation. We can then epoxy multiple standoffs between the rings, to ensure all heights and alignments are correct.

Calculations

It is extremely important to perform calculations before all else, both to make sure your design is feasible and so that you can select and reference what parts/materials you are planning to use. The specific calculations will vary for each design, but the quickest way to think about what calculations are needed are to think about the forces placed on each part and on all surfaces that connect parts together. We should also check the calculations for the events that take place (black powder and spring actions). For our design above, our main concerns are:

• Can the black powder we have break the screws?

  • This is dependent on several factors, mainly:

    • mass of BP (depends on volume of drilled hole)

These are some of the important calculations needed, however the more you can think of, the better. Make sure each calculation gives us a reasonable factor of safety (use your good judgement).

Integrating with the Rocket

Sources

Before PDR

1. Material Choice: Fiberglass (Balsa wood too weak given geometry and speed)

2. Geometry Options

Perfectflite StratoLoggerCF

This altimeter will be used in both the upper stage main and drogue parachute deployment.

Purpose (Upper Stage Main): Dual Side, Dual Deploy Entails: Pyro leads to main and drogue (redundant), deployment based on elevation and velocity.

Purpose (Lower Stage Main): Single Side, Single Deploy Entails: Pyro leads to main (redundant), deployment based on elevation and velocity.

Specs:

• Works to 100,000 feet MSL, audibly reports peak altitude and maximum velocity after flight.

• Stores 16 flights of 18 minutes each (altitude, temp­erature, and battery voltage at 20 samples per second) for download to a computer with the optional DT4U USB interface. Hi-speed sampling and storage of battery voltage serves as a useful aid in diagnosing intermittent problems with your battery, switch, and wiring. All data are preserved with power off.

• Deploys drogue and main chutes with audible ematch continuity check.

Manual:

Altus Metrum EasyMega

The Altus unit comes at a hefty cost, but has the advantage of being able to provide angle caculations. using two different altimeters for the same deployment is not advised since it would require two different switches.

Purpose: Lower Stage Parachutes (Drogue and Main, DSDD), Separation Mechanism Entails: 3 additional programmable pyro events for separation mechanism (redundant).

Specs:

• 2.25 x 1.25 inch board designed to fit inside 38mm airframe coupler tube

• Supports dual deployment and 4 additional pyro events.

• Pyro events are configurable and can be based on time and various flight events and status, including angle from vertical (for safety in staging and air start flights).

Manual:

Eggtimer Quantum

Purpose: Airstart (Motor Ignition)

Entails: Single lead to motor ignitor

Specs:

• 66mm x 25mm, weight ~12 grams

• Dual-ended output - pyro igniter is dead until near deployment for safety

• Records altitude up to 60,000 AGL

• Drogue programmable 0-3 seconds after noseover, main programmable from 100-2000 feet

The Common Avionics System (CAS) is a system for Avionics hardware development with the primary motives being to reduce hardware development time by better leveraging existing verified designs. CAS achieves this by splitting functionality into separate modules. This allows each module to do one thing and do it well, without having to redo aspects of the system that have already been done. CAS will allow Avionics to more easily support new projects and will reduce risk (in the long-term) by reusing well-tested designs.

CAS Board standards document (describes how to develop modules for CAS): https://docs.google.com/document/d/1TXryu3QcSKlMYy4J2YmgYoLP_nRUAluCNtpA56hADVI/edit?usp=sharing

Terms

Stack: A set of modules placed vertically with standoffs separating them.

Module: A single printed circuit board (.062" thickness) that has the hardware to satisfy a certain function.

Dimensions

A module in the stack

See image below for cross-section of a stack (specifically of a module). The modules are square PCBs with 4 mounting holes in the corners (large filled yellow circles with blue-green halo). The arrays of smaller empty yellow holes are header pins for connection to other modules in the stack.

The side to side distances are 2.5 inches and mounting hole to mounting hole distances are 2.2 inches. The space from the top of a module to the bottom of another module is 0.6 inches.

CAS Bus

All of the modules in CAS share a common 80-pin bus. Not all of the pins have functions assigned yet, but they may be assigned in future modules. The CAS modules must never conflict with the common bus pin-to-function assignments. The pin-to-function mapping is recorded in this google sheet:

The types of pins that appear on the bus are:

• Power

  • +3.3V

  • +5V

  • +BATTERY

Power

The entire CAS stack's voltage rails (3.3V and 5V) are powered by a power management unit located on the core board. This power unit on the core board recieves +7.3V DC from an external battery. The entire CAS stack generally draws below 50 mA of current when not doing power-intensive tasks.

Disassembling modules from the stack

To separate modules from each other, use a flat-head screwdriver as a lever, as shown in this picture:

Overview

The pyro module consists of eight connectors which can each light a blackpowder charge. Each connector is controlled by a mosfet, and if the mosfet allows current to flow through the connector, then the blackpowder charge is ignited.

The core module controls this by sending I2C messages over the I2C0 bus to the I/O expander module. The I/O expander module connects to eight mosfet drivers which drive the mosfets. The I2C messages that come to the I/O expander can tell it to set off certain blackpowder fuses.

The I/O expander also features three address bit jumpers, which can be manually connected or disconnected to change the I2C address of the I/O expander, to avoid I2C address conflicts.

Overview

The Radio module contains an RFM69 radio transciever module (with an attached antenna) whose purpose is to transmit data from the rocket to the ground station in real time. The radio module also contains a SAM_M8Q u-blox GNSS chip which can determine time, latitude, longitude, and altitude. The micocontroller can communicate with the radio through the SPI0 bus, and communicate with the GNSS chip over the I2C1 bus. There are also a couple of optional extra I/O interface pins on the GNSS module that can be connected to external jumper wires.

The radio's output can be sent either to the antenna or to an SMA cable (for testing what data is sent). There are two jumper pins on the board, JP1 and JP2, which control which of the two destinations is connected to the radio's output. JP1 can be used to manually set the radio's output between to the antenna or to the SMA. JP2 can be used to override the selection on JP1 and have the selection be made by the Microcontroller instead. Note that JP1 is on the top of the board and JP2 is on the underside.

The current version of the radio board also has one extra connection made with a white soldered-on wire, which connects the DIO0 pin on the radio transciever to the A20 pin of the CAS Bus (INT 8). This could be used in the future to program the radio transciever to send an interrupt over the DIO0 pin which would reach the Microcontroller at interrupt pin 8.

Normally, the radio should be operated at either 915 MHz or 433 MHz.

The prop module is currently still in development. The prop module is unique in that it consists of three boards, not one, since the components would not all fit on one board. Also, the prop module requires a separate power supply connector because one of the components (a solenoid) requires a +24V power input, which is greater than the battery can supply.

The current plan for the prop board will include connectors that attach to several sensors and actuators used in the propulsion system. These sensors and actuators are not on the boards themselves, but are instead wired to the connectors on the edges of the boards.

The main specifications for this module are:

• 5 Pressure Transducers

• 3 Load Cells

• 3 Thermocouples

• 3 Servos

• 2 Solenoids (to open valves)

• Oxygen Flow Meter (Not yet decided if we should include this)

Overview

The Core Module contains the main MCU (an STM32F401RE chip), three sensors (BMP388 altimeter, BNO055 IMU, MAX17049 fuel gauge), an SD card holder for data logging, a UART debugging port, and USB and JTAG connectors. It also provides power for the other modules through the CAS Bus 5V and 3.3V power rails.

The STM32 microcontroller connects to an I2C bus (numbered I2C3) that does not connect to the CAS Bus, bus instead conencts only to the three sensors on the core board itself. The microcontroller also connects to an SPI bus (numbered SPI3) that does not connect to the CAS bus, but instead connects to the SD card holder and the SPI-to-I2C translator. Lastly, note that the I2C2 bus on the CAS bus does not connect directly to the microcontroller, but instead goes to the SPI-to-I2C translator.

The core board also features a "user button" and "user LED" for testing purposes. There is also a RESET button, but this button does not do anything unless there are jumper pins attached to the RESET jumper.

At the time of this writing, none of the three sensors have been soldered onto the board yet because we have been unable to buy them so far (except for the BMP388, which we bought recently but haven't soldered on yet).

Interface

Test Procedure

For testing, assemble the module and plugin a battery supplying 7.3V.

1. Test bus power sources. Make sure the voltage of all power pins match the specification.

2. Check USB. Connect USB to the computer and see if the flasher can recognize it.

3. Run echo and LED test. See if we can flash the chip through the debugger, then check if the user LED is blinking and if the UART outputting the correct message.

The radio-revised board is still in development. The plan for this board is to use an AT86RF215 module as the radio transciever, which can transcieve over two channels independently at different frequencies.The core board will communicate with the AT86RF215 through LVDS signals, which are output by the FPGA on the core-revised board and travel over LVDS pins on the cas-bus.

Most of the design for this module is directly copied from the cariboulite radio board design (which also uses an AT86RF215) here:

Purpose

DAVE is the payload subteam's primary research project intended to be flown on a 6 inch diameter rocket. DAVE is planned to consist of a semi-autonomous, passively stable glider, a mechanism to deploy the glider from the rocket, and associated test platforms.

Deployment

DAVE deploys just after apogee, or the apex of the rocket's flight. In doing so, it uses its ejection mechanism to leave the payload bay in the launch vehicle's interior and pursue its own free-fall path to the ground. Doing so allows DAVE and its cargo to undertake a longer, more controlled flight separate from the parachute and the rocket fuselage.

Aerostructures

Due to DAVE's full flight structure needing to be contained within a 6" diameter tube, the glider must be collapsable. In particular, both its primary wings (of Rogollo type) and its elevators must be collapsable in some fashion.

Additionally, the manipulation of our weight, lift, and drag force vectors are essential to DAVE having a controllable flight. DAVE currently has no mode for producing thrust, but a thrust-producing cargo may be pursued in the future. Calculations to determine the correct geometries (including wing sizing and placement) are located on the DAVE Trello board under Aerostructures.

Vehicular Control

As we would like to be able to control DAVE's flight from the ground, we will need on-board avionics. These avionics will control two types of control surfaces on DAVE: elevators and rudders. The elevators give DAVE control in the roll and pitch directions, while the rudders give the glider yaw control. Both of these will be located at the rear end of the vehicle - the Rogollo wings will be fixed and uncontrolled.

Experimental Cargo

The grand purpose of DAVE is to carry onboard experiments that benefit from its unique deployment and flight pattern. Although the current designs for cargo carrying are not set, a goal is to have a modular interface, so any cargo concept that matches can go aboard.

Initial tasks assigned as follows:

The core-revised board is still in development. The plan for this board is to use a raspberry pi compute module 4 ("rpi CM4") as the microcontroller for the board. The board will also have an ICE40 FPGA that serves as an I/O expander, since the rpi CM4 has a limited GPIO pin count.

The specification for this board includes the following components:

• rpi CM4 microcontroller

• ICE40 FPGA

• 2 camera connectors

• 2 HDIMI connectors

• An SD card slot

• A microUSB port (with an ESD protector)

• 3 sensors (the same as on the original core board)

• a PCIe connector (we still haven't fully decided if this should be added or not)

The rpi CM4 has 45 GPIO pins that can be mapped to various functions. See pages 8 and 9 of the rpi CM4 datasheet () for the full list of possible pin assignments. See the "GPIO to CAS Module" google doc () for the list of pin assignments that we decided to implement.

Note that GPIO0 and GPIO1 have three functions--they can be used as either SMA pins to connect to the FPGA, or as GPIO pins to connect to one of the camera connectors, and on top of that, both pins are also used as UART debugging pins.

The rpi CM4 will use the "secondary memory interface (SMI)" to communicate with the FPGA through the pins that have been assigned SMI functionality.

This schematic describes the overall plan for the entire module, which shows how each of the components should communicate:

This core module is largely inspired by the design from the rpi CM4 I/O board, which features many of the same components (HDMI, PCIe, camera connectors, etc) also connected to an rpi CM4. The I/O board design is located here:

The symbol and footprint for the rpi cm4 are located here:

Welcome to the IREC 2020 & 2021 Projects page! You can find both technical and non-technical information about our 2020 and 2021 project here.

Is this FAQ a good place for writing technical design decisions?

Heck no! There are other places to do that.

What's the point of DAVE?

Payloads such as the muon detector benefit from extended time in the air. Other potential payloads may benefit from a more gentle descent, or placement in a specific location. Additionally, DAVE-specific payloads may be interesting, such as aerial mapping, rocket-spotting, etc.

Why not just like, build an RC plane?

Getting a conventional UAS to this altitude can actually be quite difficult at this scale. While it is certainly doable, there may be applications for this sort of vehicle in a situation where rapid response and having a presence at these altitudes is important. The autonomous functionality is critical in these scenarios. For example, while fighting a fire, being able to quickly get a picture from the sky may be useful for firefighters on the ground.

I have a cool idea for a payload that should go on DAVE. What should I do?

Write it down on the Trello card and message in #payload-dave! Even if we are actively focusing on IREC payloads, we can always be writing down good and interesting ideas.

Harness Components

1. Quick Links- metal rings that connect the shock cord to the u-bolts and also connect the parachutes to the shock cord.

2. Shock Cord- durable kevlar rope that holds all of the rocket together when parachutes are deployed.

3. Bulkheads- metal cylinders that are important for structural integrity. The u-bolts thread through the bulkheads.

4. U-Bolts- Are connected to the shock chord by a quick link.

5. Swivel?

Fold the Parachutes (Ideally a two person job)

1. Dedicate a 10 by 10 foot area to fold the main chute.

2. Lay out the parachute on its side and gather the shroud lines (the string coming from the edge of the parachute). This means that if the parachute was fully open with the inside facing up and you were standing at the center of the parachute holding all the shroud lines, that you move to the side folding it in half.

3. Make sure the shroud lines are untangled.

If confused watch the video attached.

The goals of the redesign of the avionics sled for the IREC 2020 rocket were the following:

1. Optimize the avionics bay for a 6" rocket

2. Address wiring concerns from AirBears to improve ease-of-use during launch

The new chosen design was an I-beam model, in which the batteries were placed in a center section of the sled and one altimeter was mounted to each side, as shown below. This design somewhat improved the space usage in the vertical direction, but there was significant unused horizontal space. The Recovery subteam selected this design because they felt it was more important to be able to wire the altimeters efficiently at launch than to use the least possible space.

Avionics Sled as viewed from back. Batteries are placed in middle centrals and the second altimeter is in the corresponding position on the other side of the sled.

• Sand Paper

• Filers

• Phillips screw driver

• Drill and drill bits

• Respirators (when filing fiberglass)

• Epoxy (JB Weld ColdWeld ™️ Steel Reinforced Epoxy)

• bulkhead jig (designed to correctly place bulkhead and keep level

Procedure

Unfortunately for this assembly/manufacturing process to epoxy the avionics bay into the airframe became more inconvenient due to the need to epoxy the door nuts to the airframe. As a result, we must assemble the av bay in the airframe tube layer by layer. The components once within the av bay will no longer be accessible, apart from the sled and electronics mounted on it.

Prep work

• Confirm you have all required materials including tools

• Sand down the PLA and Wooden bulkheads to allow the them to more easily slide into the tube

• Sand down sled to allow for it to more easily slide into the bulkheads

Aluminum Bulkhead Manufacturing

• Insert the U Bolts into the Aluminum Bulkhead and attach the nuts on the other side

  • take care to make sure the nuts are level

• Add epoxy to the underside of the bulkhead between the nuts, ubolt, and bulkhead

• Add epoxy to the top of the bulkhead at the interface of the ubolt and the holes

Assemble the AvBay for Test Fit

This is done so that we can be assured of the fit of all components before we assemble the av bay within the tube

• Begin first with the sled and work from the "inside" outwards

• PLA bulkheads around the sled on the top and bottom

  • this is a great time for any final filing to ensure the slide can slide in and out smoothly

• Slide the threaded rod past the first bulkhead, and add 2 nuts

Assembly of AvBay within the Tube

Note that this is especially difficult and limited for BFO specifically because of the accessibility and mounting requirements of the av bay

1. Epoxy in the first bulkhead

• Begin epoxying procedure using JB Weld:

• The procedure for the first bulkhead is the airframe standard for epoxying bulkheads into the airframe tube

• The first bulkhead (put in place prior to the sled) can be done normally, with two precise fillets on either side done by hand.

Primary changes to Airbears designs include improved wiring and accommodations for fiberglass tubing. This project also is significantly heavier, has twice the target apogee (10k ft), and has a much larger diameter (6") than Airbears.

Further improvements will be made relating to the holders to secure them to the bulkhead instead of having them unrestrained during launch

Overview

Many systems within a rocket are controlled by electronics, such as the parachute deployment systems, the motor ignition systems, and with our latest SSEP project, the stage separation mechanisms. These electronic controls are known as avionics, and they are essential to the function of the rocket, but they can be quite delicate and must be in proximity to the systems they are controlling so they can be wired effectively. The avionics bay houses these avionics in a relatively central location in the rocket and in such a way that the avionics are kept safe throughout the rocket's flight.

Types

We use two main types of avionics bays: axial designs and radial designs. These names refer to how each design is installed into the rocket. Axial av-bays are inserted through the airframe tube along the tube's long axis, and radial av-bays are inserted radially through the side of the airframe tube, through a door in the tube. All radial av-bays have a sled, which houses the avionics and is the actual component to slide in and out of the airframe tube. Some axial av-bays have a sled design so that the avionics can be accessed radially as well, but this is not the case for all axial av-bays.

Full avionics bay for Bear Force One with the radially installed sled highlighted in blue (Right), and sled from avionics bay for Bear Force One with altimeters to control the parachute deployment (Left):

Components

There are two main types of components discussed here: structural components and electronic components. The structural components serve to house the avionics (the sled) and to connect the inner structure to the rocket’s frame (bulkheads, u-bolts, etc.). The electronic components are the avionics themselves, notably the altimeters and CAS, along with their power supplies.

Structural Components

The following outer structural components are found in practically every av-bay, no matter the design:

• Bulkheads: These usually metal plates connect the rest of the avionics bay assembly to the frame of the rocket.

• U-bolts: These u-shaped bolts are fastened to bulkheads and connect the bulkhead, and therefore the avionics bay assembly, to a parachute assembly. Typically there is a fore u-bolt that connects to the drogue chute assembly forward of the av-bay and an aft u-bolt that connects to the main chute assembly aft of the av-bay. However, if there is only one chute assembly connected to the av-bay, as is the case with the lower stage of the SSEP rocket, only one u-bolt is needed.

• Av-bay rods: These rods provide additional structural support for the av-bay and are fastened with wingnuts. They can be seen in the av-bay for Bear Force One as the two vertical rods, shown at the bottom of this section.

Bulkhead + u-bolt assembly from Jay’s CAS-compatible 5.5” av-bay:

Additional outer structural components can be found on some av-bays, depending on their design:

• Additional outer bulkheads: Some av-bays, like the one in Bear Force One, have an additional set of outer bulkheads so that the rods and the u-bolts have four connection points instead of two. These additional outer bulkheads are depicted in the image below of the av-bay in Bear Force One with a slightly blue hue.

• Av-bay door: Any av-bay with a sled needs to have a door to access the sled. By default, any radial av-bay will have an av-bay door. This is one of the drawbacks to a radial av-bay design, as any hole in the airframe, such as an av-bay door, could potentially negatively impact the stability of the airframe.

Av-bay airframe tubes for Bear Force One with cutout for av-bay door:

The following are the main inner structural components of a radial av-bay or an axial av-bay with a sled:

• Sled: This structure houses all the avionics in a radial av-bay and some axial av-bays, and is designed to slide in and out of the av-bay assembly through the av-bay door for easy access to the electronics. It is convenient, but requires an av-bay door.

• Sled housing: This structure houses the sled and essentially gives the sled something to slide into. There are channels cut into the inner edges of the housing that the sled can slide into so that it is held firmly in place.

• Inner bulkheads/sled housing bulkheads: These bulkheads have a large section cut out and the edges of the cutout grooved so that a sled can slide directly into the bulkheads instead of sliding into a housing. These are used in the av-bay for Bear Force One, shown below highlighted in blue.

Sled from Jay’s 5.5” CAS compatible av-bay (Left), and corresponding sled housing from Jay’s av-bay (Right). One can see how the sled could slide into the housing and be held still by the grooves cut into the housing that match the rails on the sled:

Avionics bay for Bear Force One with upper inner bulkheads highlighted blue:

Avionics Components

The following components are the avionics in a typical av-bay along with their associated components:

• Altimeters: These measure the altitude of the rocket during its flight and are used to trigger the parachute deployment.

• 9V batteries: These are used to power the altimeters in flight. They are encased in a housing we have designed.

• 9V battery cases: These cases keep the 9V batteries safe and allow them so be more easily secured to the avionics bay.

PerfectFlite Stratologger altimeter (first), LiPo battery for CAS (second), and 9V battery inside custom-made casing (with cover removed to view the battery) (third):

CAS stack put together (without antenna):

Other Av-bay Designs

Some av-bays are designed with a specific, unique purpose in mind, so they may have different designs to fit their specifications. For instance, an additional av-bay aft of the main parachute assembly was needed on the SSEP rocket in order to trigger the stage separation system and to ignite the upper stage motors. However, there was not much space to fit this av-bay. So, a small axial av-bay was designed by Hadar to meet these requirements, shown below. Note that it does not have a sled and an access door but instead splits into two accessible parts that are then clamped together when installed into the rocket.

Introduction

Main Contributors and General Progress

The IRIS project combines two originally separate projects (IRIS Legacy and Muons) into a 1U CubeSat unit to conserve space in the payload structure.

Rajiv Govindjee, Jason Xu, Bryant La and Ocean Zhou are the main contributors to this project. Rajiv and Jason worked on the first iteration of IRIS while Jason and Ocean worked on the first iteration of Muons. It was decided for the sake of efficiency and adventure that the two detectors should be combined into one complete detector. Jason was heavily responsible for the electrical design of IRIS, in particular the printed circuit boards (PCBs). Bryant and Ocean worked on the mechanical integration of IRIS to the rocket. IRIS is currently in its assembly phase, although with the impacts of the COVID-19 pandemic, the assembly phase has faced delays.

IRIS Overview

IRIS Records Information via Sensors (IRIS) is a sensor suite printed circuit board (PCB), outfitted with an accelerometer, a gyroscope, a magnetometer, a barometric pressure sensor, and a High-G accelerometer. Its function is to record various flight data (acceleration, angular velocity, absolute orientation, barometric pressure/altitude) to assist in developing flight-critical avionics and validating current and future simulation work with respect to flight dynamics.

The IRIS assembly consists of three main PCBs. In order, from bottom to top, the three main PCBs are:

1. a power distribution board (IRIS-Power) connected to a two-cell (2S) 8.4V lithium polymer (LiPo) battery

2. a primary IRIS board (IRIS-Core)

3. an auxillary IRIS board (IRIS-Core)

Inspiration

The first iteration of Muons was based heavily off of Spencer Axani's project. He is a current particle physics PhD student at MIT! This is the that contains all the info about his project. The GitHub page that includes all the software, details, PCB soldering guidelines for this project can be found . Our first detector was basically following his step by step instructions and recreating his detector. So to Spencer, a massive massive thank you!

Optional Sensors (Reserved for Future Use)

In addition to the motion sensors, there are two optional components on IRIS that are currently unpopulated but can be implemented in the future.

GPS

IRIS supports the addition of a GPS module () in the future.

Pitot Tube Sensor

IRIS supports the addition of a differential pressure sensor, for implementing an external pitot tube in the future.

Electrical Hardware Design Overview

The electrical hardware (PCBs) are avaliable on our cadlab:

IRIS-Power

IRIS-Power occupies the bottom most board of the 3 board stack. The primary purpose of IRIS power is to output regulated power from the 2S LiPo, gauge the LiPo's charge with a battery fuel gauge IC, and provide a backup source of power in case the battery fails or is suddenly disconnected. The backup is provided through 2 supercapacitors that can provide several minutes of backup power.

Additonally, the power board has the ability to automatically switch to a connected USB-C power delivery adapter in order to save battery charge during bench-top testing and programming.

IRIS-Power provides 5V for the Teensy 4.1 MCU on IRIS-Core, 3.3V for other extra ICs, and 29.5V for the photo-multipler Muon sensor.

IRIS-Core

IRIS-Core is the primary module of the 3 layer stack. The middle board of the 3-layer stack is a full-fledged IRIS-Core board, while the top board of the 3-layer stack is a partially populated IRIS-Core board.

The main MCU of IRIS-Core is a , an Arduino compatible board.

The full-fledged middle module contains a Teensy 4.1, IMU breakout board, High-G accelerometer breakout board, and a muon sensor.

The partially-populated top module contains a Teensy 4.1 and a muon sensor.

Very Useful Diagrams

For some very useful diagrams detailing the pinouts, peripherals, and power flow connections, see the following pages:

Design Log and Updates

Mechanical Design

(12/06/20): There is no way to fasten a nut on a screw from inside the enclosure. The enclosure will be secured to the T-slotted rails with eight screws going through eight brackets, held in place by having the screws serving as pegs into slots. The screws are at different heights, so interference is not an issue.

Electrical Design

(12/06/20): The backboard support PCB has been replaced with the stack connectors (pin headers) pictured below. This was done for simplicity of design, to reduce the space taken up by the PCBs, and to prevent interference between the vertical threaded rods and the fasteners attaching the enclosure to the T-slotted rails. The enclosure and spacers have been updated to accommodate this change.

Manufacturing

Engineering Drawings

Prototyping Processes

The enclosure measures 7.9 cm x 7.9 cm x 10.635 cm, and can be manufactured via 3D printing with PLA material.

Progress

(12/06/20): The PCBs were ordered and arrived. Bryant La will solder the components on campus with a reflow oven over winter break, with Jason Xu's remote assistance. Boards will be shipped to Jason Xu for him to attempt soldering without a reflow oven, though he does not need to succeed for the project to progress.

The BOM is being finalized and the parts will be ordered soon. Once fully manufactured, the code will be rewritten to interface with the combined IRIS/Muons.

(01/25/21): Both Jason Xu and Bryant La are near campus and will work together to finish manufacturing for this project.

(02/14/21): The power board and one of the sensor boards have been soldered. Jason Xu and Bryant La will need to procure the existing completed Muons boards from the Supernode locker to move their scintillators onto the new IRIS/Muons boards. After soldering of the final board is complete, efforts will be focused on writing the board firmware.

Launch Results

At the time of writing (May 2020), due to power and launch issues, IRIS has been unable to record data during flight for any launch. Data obtained so far has been limited to what IRIS senses during assembly on the ground, which showed little variability as expected; however, the values IRIS reports are accurate (e.g., the barometer shows atmospheric pressure near sea level), which is evidence that the sensor suite functions as it should.

Muons has been launched like IRIS and was able to record data during flight. However, due to the minor detector malfunction, relating to multiple data files being saved for unknown reasons, the data obtained was unable to offer much use; besides total muon count, it was impossible to pinpoint which files corresponded to different points during the flight. Nonetheless, the fact that the detector was able to record muon count and that the muon counts increased over time indicate that the detector is able to function properly during flight.

The previously assembled detectors have been tested twice. The first test was to ensure that the measured voltage signals matched the expected values, in which the detector succeeded. The second test measured how the angle of the scintillator (with θ = 0° being the horizontal orientation) affected muon count measured within an interval of 1 minute. This was done to decide the orientation the detector was to be at inside the rocket. Having the scintillator at a horizontal orientation yields the most counts.

References

This report is intended to be used as a reference for all IREC 2020 payloads, as a preliminary description of all projects.

Excerpt (Abstract):

The Payload subteam of Space Technologies And Rocketry (STAR) at the University of California, Berkeley focuses on launching scientific instruments and experiments to high altitude: we are what makes rockets worth flying. This academic year, the payload projects, all integrated into a 5U CubeSat payload structure, include: onboard cameras, a dual sensor suite and cosmic particle detector, a microbial fuel cell, and an active stabilization system. The overarching mission objective is to record data and test experimental systems in-flight.

Ballast

Primary Payload Structure

Tie-down rods

Purpose: To constrain the payload structure along the long axis of the rocket

Important design considerations:

• We used flight data and openrocket simulations to estimate maximum acceleration loads at 16 g's

• Two #4 threaded rods are spec'ed to a FOS of ?????

• @Ritvik something about having two possible orientations to minimize issues in assembly

What we have one:

• Complete test fit of design

What is left to be done:

• Add to launch-day parts list

Lateral support system (i.e. leaf springs)

GPS Mounting

GPS mounting is designed to attach the GPS module on the inside of the nosecone. In the designing process, two important factors were considered, stability, and suitability. Also, there were restrictions which are the GPS mounting can't touch the top metal plate of the structure and the GPS antenna should be mounted straight.

For higher stability of the GPS module, mounting has 6 zip tie holes on the front. There are two ways to fix the battery and GPS module into the mounting. 1) Using zip tie, combine together battery and GPS module. 2) Or, insert the battery and the GPS module into the mounting and tied them up together. The GPS mounting and holes are small, so a tweezer is needed to assemble it.

For the suitability of the mounting, the rear side of the mounting is designed with the same curvature as the inside of the nosecone. Also, the curvature was measured at 10.5 inch far from the top plate of the primary payload structure.

• Payload Structure :

  • 1/16” Steel ballast plates (32)

  • 9” Miniature T-slot rails (8)

ASSEMBLY

1. Place 4 long t-slot rails on each corner of the top base plate.

2. Attach rails to base plate through 2 L brackets on each corner of base plate.

3. Using 2 M3x10 screws and 2 hex nuts on each corner, fasten each screw with all screw heads facing out of the opposite side of the t-slot rails.

Background

The Microbial Fuel Cell (MFC) was inspired by NASA Micro-12 studying MFCs for the purpose of wastewater treatment and electricity production. The purpose of our MFC payload is to determine the effects of rocket launch and flight on the performance and health of the MFC.

The first iteration of MFC was designed to to use wild-type Shewanella oneidensis bacteria in a LB broth with platinum electrodes. The bacteria were sourced from Adam Deutschbauer's Lab at LBL. However, due to the difficulty of the project and a fungal infection that wiped out the bacterial culture, we decided to pivot to a more robust and simpler design.

The second iteration of the MFC was designed to use electrogenic soil bacteria from locally sourced soil, mixed with distilled water with graphite electrodes. The maintenance of this iteration of the MFC was much easier and a control MFC of this design was manufactured to gather voltage data over the course of 2 weeks.

• PLEASE learn how to solder printed circuit boards. Though it is not hard to pick up, learning understandably still takes time. At Cal, you can either practice soldering in the Chen-Ming Hu Lab in Cory Hall Second Floor (aka SuperNode), or in the Electronics Lab in Jacobs Hall. Here's a tutorial to get you started: https://www.youtube.com/watch?v=Qps9woUGkvI

• Find a way to machine the scintillator if the one you bought is not already machined. The manufacturing drawing is attached below: https://github.com/spenceraxani/CosmicWatch-Desktop-Muon-Detector-v2/blob/master/CAD/Scintillator%20CAD%20file.pdf

• After you purchase the SiPM and it arrives, PLEASE place it somewhere safe and load-free. Do NOT crush the SiPM as it is very delicate (and expensive!)

Assembly Instructions

1. Buy all required electrical components

2. For the Arduino Nano, be sure to upload the coincidence.ino code to it, as this ensures a muon will be counted! Refer to pdf attached below for specific detail.

3. Solder the electrical components onto the 3 PCBs (Main Board, SiPM Board, SD Card Board). Use this as the guide to know where to solder the components:

For greater detail, read the entire instruction manual:

(Please Read!) Miscellaneous Files/Instructions

• Please make sure you have access to the STAR GrabCAD! If you do not, you will be unable to locate any of these files*

• Also make sure you have SolidWorks 2019 and Ultimaker Cura 4.4.1!*

• Please also purchase a Makerpass for Jacobs Hall Access. It will make your life so much easier for assembly*

Plan for IREC 2020

While we did collect data from our AirBears launch, it correlated only time with muon count. Furthermore, 4 separate SD files were created, meaning we had no idea at which height did the counts correspond to, making the data not as useful.

To combat this, our beloved payload lead Jason Xu (Woo!) is working to merge IRIS and Muons together as IRIS records height (through pressure) which allows us to see how muon count correlates with other parameters besides time. Excited events to come!

Sources

Description

The Cameras project uses the Mobius Maxi camera mounted on a custom base plate that is epoxyed on the airframe's exterior with a custom shroud.

Two shrouds shall be mounted. The camera shrouds have been optimized to maximize field of view while minimizing impact to the aerodynamics of the airframe, allowing the cameras to record the flight with as much detail as possible without being a detriment to vehicle performance. The recorded results are retrieved from an in-camera SD card post-landing. The captured footage should theoretically document the rocket in flight even after it escapes visual range from the ground.

System Weights, Measures, and Test Reports

Each Mobius Maxi measures 7.1 cm x 3.5 cm x 1.8 cm and weighs 52 g. Each shroud measures approximately 13.2 cm x 4.1 cm x 3.8 cm and will be manufactured from PLA material using 3D printing.

At the time of writing, no in-air flight recordings have yet been captured. Recording testing has been performed, but the full extent of camera capabilities have not yet been documented. A battery life test has been completed along with a shake test to mimic the turbulance he camera would experience while on the rocket. The Camera was able to record for over 2 continuous hours with minimal quality degrigation as a result of shaking. Worst-case test is planned in the future, with active external heating to mimic launchpad conditions.

CADS

CADs are for the camera's custom shroud.

Hazard Analysis and Risk Assessment

The primary risks and failure modes associated with Cameras are depletion of the battery and structural failure of the shroud during flight. The camera shroud could sheer off from the baseplate, take damage from shaking from not being properly secure in the shroud. Test on different epoxies are being conducted to determine which would best minimize the risk of the camera seperating from the body of the rocket, with the possibility of grooves being put in place to increase surface area contact.

Without power, the Mobius Maxi camera cannot record data. Mitigation strategies include fully charging the camera the night before and setting the video recording settings to their lowest power consumption setting.

Structural failure of the camera shroud would cause parts of the shroud or the entire shroud to shear off of the launch vehicle, potentially even changing the vehicle's trajectory. Mitigation strategies include printing the shroud at higher densities and out of stronger materials, and checking again that the shroud is properly mounted before launch.

Assembly, Pre-flight, and Launch Checklists

Pre-Flight

1. Charge both Mobius Maxi cameras with MicroUSB cable.

2. Place one MicroSD card into each camera.

3. Configure settings on both cameras to be appropriate to flight mission and launch conditions, including recording automatically when power is turned on.

Post-Launch

1. Retrieve all payload components from the downed rocket.

2. Turn cameras off and stop recording.

3. Disassemble camera assemblies.

4. Read and analyze data from the SD card.

Some info:

We have a base containing large electronics supporting our servos and arms. Each servo provides rotational motion to one axis with range of +-90 degrees (180 total), with an initial configuration of all axes being orthonormal to each other. The first servo is attached to our base, which controls an arm that our next servo is mounted to. This second servo controls the next arm that our third servo is mounted to. Our last servo, however, does not control an arm, instead it controls a platform, the platform which we would like to stabilize.

Inventory:

Electrical Components

All electrical components below, unless otherwise specified, we have in inventory. For everything without a number or description, assume we have one part in inventory.

• Arduino Nano

  • Connects all components together and provides communications/calculations between components.

• 1S 3.7V Lipo Battery

Mechanical Components

• Servo Bolts

• Servo Nuts

• Sensor Bolts

• Sensor Nuts

• There are many existing tutorials out there on the web that probably will provide a more detailed step-by-step procedure and description on features of Premiere Pro.

  • https://www.premiumbeat.com/blog/15-premiere-pro-tutorials-every-video-editor-watch/

• So here, we'll talk about what information you'd want to put in for a club promotional video.

• Promotional Videos

  • Objective

    • Recruitment: to attract audiences/ potential members to our club

• Recruitment Videos

  • Emphasize the variety of subteams we have (technical AND non-technical)

    • technical subteams: emphasize projects with short descriptions with minimal jargon
• Crowdfunding Videos

  • Emphasize the variety of subteams we have (technical AND non-technical)

    • technical subteams: emphasize the significance and diversity of projects within the club

Installation

SolidWorks Student Edition (2022-2023)

STAR is migrating to the SolidWorks 2023 Student Edition.

• Go to: and complete the form (first name, last name, Berkeley email address, select “student team” on dropdown)

• Under product information

  • Select Yes (I already have a serial number)

If presented with the option above in the installer, it is recommended to upgrade rather than create a new installation to save space.

On the summary page of the installer, you can select which products you wish to install. At minimum, you will need the 7.1GB SolidWorks package.

Instructions on downloading and installing SolidWorks Student Edition 2023 can also be found .

If you need more help, can help walk you through the process!

Downloading ANSYS

To download ANSYS Student, navigate to https://www.ansys.com/academic/free-student-products. Scroll down and select ANSYS Student, then click on the Download ANSYS Student 19.1 button that appears below.

Installing ANSYS

After the folder finishes downloading, unzip it with your favorite unzipping tool and navigate to the new folder. Then, open a file found inside the new folder labeled Setup.exe. Click the Next arrow in the bottom right corner as you progress through the setup. Once installed, you can open ANSYS by searching "Workbench 19.1" in your computer's start menu.

Known Issues

We have experienced an issue once where the workbench application did not install. In this case, delete the ANSYS program file in your C drive and repeat the process above.

VMware is a software that is free for Berkeley students that allows you to run windows on a non-windows computer which will allow you to install and run SolidWorks. Bootcamp is a program native (already downloaded) on macs that also allows you to run windows on a mac. Both options have some pros and cons which will briefly be detailed below. If you already know what you want to use, skip to the directions. If you have any questions/problems with the directions feel free to contact Ananya Subramani on the STAR Discord.

VMware and Boot Camp Similarities

• Allow you to run the latest version of Windows

• Can run SolidWorks

VMware and Boot Camp Differences

• VMware is easier to start up (like starting up a browser or generally opening up an app)

• Boot Camp requires you to restart your computer whenever you want to run in a windows environment

• Boot Camp requires you to permanently partition your hard drive which cannot easily be changed after it is done.

My personal reccomendation is to use Boot Camp if you plan to use solidworks very actively, and VMware if you just want to look at files in more detail than grabcad shows. If you have a lot of RAM though, you could probably just go with VMware and be fine

How do I get Boot Camp/VMware to work?

Step 0- System Pre-requisites

You will need the following things, or the download will probably fail at some point:

• Mac made in 2011 or later

  • exception: 2012 Mac Pro “Quad Core” using the Intel® Xeon® W3565 Processor

• OS X 10.11 El Capitan minimum required

Step 2- Get a Windows License

Start by going to this website: and taking the link for "personally owned devices." You should be able to navigate to this screen:

Click on Windows 10 and add it to your cart. If you want to use VMware, go to step 2.5, if you want to use Boot Camp, check out and go to step 3.

Step 2.5- Get VMware

From the same place you should be in step 2, go to the VMware tab and download VMware Fusion 11.x (for Intel-based Macs). You should get to this screen:

Add VMware to your cart and check out.

Step 3- Download Windows Operating System Disk Image

In the details of your purchase that you made in step 2, there should be a windows license number, you will need that.

My screenshot doesn't have a Windows license number because it's been more than one month since I "bought" it but yours should.

Once you have access to that license, navigate to this site:

Select the proper language, and download the 64-bit version

VMware users, go to step 4, Boot Camp users go to step 5

Step 4- Setting up VMware

Download VMware fusion from the cart and open and install the application. When it asks for a number during the setup process, enter the serial number that I blacked out in my screenshot.

Once you see this screen, drag the windows 10 iso file into the place where it says install from disc/image (the default name for the downloaded file is shown below)

From here, just go through the installation steps and once you have your virtual machine configured and you can access the internet, go back to the solidworks installation guide and follow those steps *in* your virtual machine.

Step 5-Setting up Boot Camp

Using the spotlight search or some other search bar on your mac look up "Boot Camp Assistant" and open the app. You should see the following screen.

From here, hit continue and you should be able to choose your partition size, with the minimum being 42 GB, which should be fine, but if you are willing to dedicate more space to a Windows partition, go for it.

Once you've completed the installation process, you can boot into your windows partition by restarting your mac while pressing the "option" key.

Once you are in your Windows partition, you can go back to the SolidWorks installation guide and download SolidWorks.

Background

The IRIS journey started in 2018; IRIS v1 was conceived of as a project for the Hands-On PCB Engineering (HOPE) DeCal. The board was assembled in Fall 2018 and found to be relatively functional, with difficulties arising mostly due to lack of software libraries for the ICM 20948. IRIS v2 was designed and assembled in early 2019, adding rounded corners, more sensors, options for breakout boards, test points, improved power electronics, and more. IRIS v2 was also more successful on the software front; all sensors tested worked nominally, including the ICM 20948. Code for IRIS v2 can be found at https://github.com/calstar/Payload. While IRIS v2 was intended to fly on Spectre, STAR's ambitious entry for IREC 2019, Spectre was never constructed due to significant engineering challenges.

For a more detailed look at requirements and progression of IRIS v1 and v2, see the IREC 2019 documentation: IRIS

AirBears Test Flight

IRIS v2 was flown on . To prepare for this flight, the casing was significantly re-designed to integrate with the other payload (Muons) on the test flight. Software was completed to allow for continuous recording of IMU data to the on-board SD card on the Teensy.

Unfortunately, as a result of non-comprehensive assembly procedures and some time pressure to assemble the payloads, IRIS was flown while not in a recording state.

The following recommendations were made following this test flight:

• Implement some method for back-up power (capacitor, coin cell battery, etc.). This ensures writes to non-volatile memory have time to safely complete.

• Create robust procedures and test them entirely before launch. This includes all integration needed with other payloads. Add special notes if power may not be disconnected from the payload after a certain point.

• Perform as much assembly as possible beforehand. Ensure that no more than 30 minutes are needed at launch for assembly; time someone actually completing this assembly beforehand.

Current Work

The team is currently working on physical design and manufacturing for IRIS to fly in the IREC 2020 payload suite as one of 5U worth of CubeSats. Work is also underway on a potential IRIS v4 board, although not required for competition readiness. Software is the largest hurdle for the competition; some development may be required to communicate with all sensors on multiple SPI buses at once (effectively).

Sub-Assemblies

Don't add tons of small parts directly into the full rocket assembly. Always group parts together into smaller assemblies then mate that larger assembly to the rocket as a whole.

0. What is GrabCAD Workbench?

GrabCAD Workbench is an online platform to share CAD files and collaborate on projects, featuring version history tracking. It integrates directly with SolidWorks with a toolbar add-in and a desktop application.

1. Creating a GrabCAD Account

If you already have a GrabCAD account, you can skip this step.

Creating a GrabCAD account is a straightforward process, first naviagte to:

In the company details section, choose job level as "Student" first before filling anything else out. The company name section should change to school name; type "University of California, Berkeley" (or some variation thereof) in the text box.

Proceed through the signup process.

Be sure to go to your email to confirm the account.

2. Getting added to STAR on GrabCAD Workbench

STAR parts currently follow the set naming convention outlined at found under Tutorials --> Operations --> SolidWorks file conventions. All parts in STAR GrabCAD projects created after 2019 must follow this format. If you have questions, just ask in #operations!

Message the email you used to sign up for GrabCAD to the Operations Lead (@mcelly#1609) along with a copy of the previous paragraph on naming to obtain an invitation to STAR's GrabCAD page. Let them know which projects you need access to, if possible.

3. Downloading the GrabCAD desktop application

The GrabCAD Workbench desktop application allows you to sync CAD files from your projects so that you have a local copy on your computer. It also installs the companion SolidWorks toolbar.

Navigate to the following link to download the installer:

Continue through the installation process. After completing the installation, be sure to log in with your GrabCAD account.

4. Next steps

You may want to unsubscribe from Workbench emails here (there are a lot!):

Deprecation Notes

As of August 14, 2018, CalSTAR's Microsoft Azure Server has been taken offline indefinitely. The server's primary role was to serve as a PDM host, a task taken over by GrabCAD. Its secondary task of hosting Converge CFD license validation was deemed to not be valuable enough to justify continued payment for the server.

About

In order to use Solidworks Workgroup PDM or Converge CFD, you must be on the same network as our server. Since we cannot physically connect to the same wifi or ethernet connection, we will be setting up a Virtual Private Network (VPN) to link your computer and the server.

(Optional shitty example) Why do I need to be on the same network as the server? How does a VPN help?

As a very generalized example, you can think of a network as a small town, with roads connecting houses and stores. Being in the same town (network) allows you to use the roads to go from your house to the store and back (exchanging files and information with the server).

Staying with this example, a separate network would be the equivalent of a town on the other side of a river. The two towns can not interact with each other. You cannot drive from one town to the other, a home in one town cannot visit a store in the other.

This is representative of your computer and the server right now. The server cannot interact with your computer, and your computer cannot interact with the server. To have any interaction between the two towns (your computer and the server), a physical connection must be made. In our example, this would be the equivalent of building a bridge across the river. You must plug your computer into the same internet (ethernet/wifi) as the server. This is not possible since Microsoft owns the server and it is probably miles away from you.

What we will be doing in this guide is setting up a Virtual Private Network (VPN). In our two-town example, the VPN is basically a quick and temporary bridge connecting the two towns. The VPN will make it seem as if the two towns are one, connected with the same roads. This lets the server communicate with your computer and vice versa. This is necessary in order to share files between the computers (essentially what the PDM and license check does).

Installing, Configuring, and Running a VPN Client

In order to set up the VPN with our server, you must install a VPN Client. The following two programs have been known to work well:

• SoftEther VPN Client [] []

• OpenVPN [] []

Choose one and download the version for your operating system. Read the notes below for your chosen program.

SoftEther VPN Client

• Make sure you are downloading the SoftEther VPN Client under Select Component

• When installing, make sure you are installing SoftEther VPN Client and NOT the Manager (Admin Tools Only)

• Proceed with the rest of the installation.

Configuring After Installation

• Launch SoftEther VPN Client Manager

• Select Virtual Adapter at the top of the window, then New Network Adapter