Lunar Lander Capstone Project
Switching to Simulated Lunar Landing
Removing need for Aerodynamics
- Design of the lander is much easier
- Dynamics of simulation are much easier
- Drag calculations are incredibly hard to do correctly.
- Very easy to calculate min and max available impulse
Focus on Lunar In-situ Resource Utilization
Dashboard Architecture
The current plan is to have a ESP8266 on the rocket that will use MQTT to talk to the ground. MQTT has the advantage of having an extremely small and resilient payload that is made for spotty connections. It is also two-way which will allow for sending commands to the rocket if that’s deemed necessary. Using Python we can easily program our own MQTT broker. The question then is what should be used as a dashboard for viewing the data and possibly relaying commands back to the rocket.
- dashboard:
- Streamlit
- Python library that is extremely easy to set up dashboards, almost to its detriment. It does make data visualization easy and would allow controlling the rocket but would be very easy to outgrow and is very limited in the ways data can be visualized beyond extremely simple line charts and tables.
- Plotly Dash
- Python library that is extremely extensible. Opposite issue of Streamlit in that its almost overkill for what we need. The way it runs would also make the architecture of the program difficult to use with MQTT. Dash is not make for streaming data.
- Grafana
- Software industry standard for viewing data with a big focus on timeseries which is very beneficial to our workload. Dashboards are also made with a GUI which would make it easy for every team member to use.
- Main caveat is that the setup is pretty complicated and requires a database to pull information from which could make data storage more complicated. (Its likely a database will be required regardless but it is something I would like to avoid.)
- Streamlit
TVC Design
Fusion Version:
- V28
- Tube Hole depth should be deeper to allow pushrod linkage to be more stable ✅ 2021-09-29
- V29
- Inner pushrod hole needs to be changed to use the linkage ✅ 2021-09-29
- Inner servo mount should be as wide as possible ✅ 2021-09-29
- Extrude11
TVC Test
The TVC Test requirements will be verified with a test and demonstration. The test stand requirements are summarized in table X.
| SSLR ID | Requirement Description | Verification Method | Verification Criteria |
|---|---|---|---|
| SSLR_4.1 | Deflection Accuracy | Inspection | Yaw and Pitch deflection |
| SSLR_4.2 | Servo Commands | Demonstration | Servo PWM Response |
| SSLR_3.3 | Software Inputs | Test | TVC Response |
| SSLR_2.1 | Device Integration | Analysis | Successful integration between microcontroller, SD card, load cells, ignition system, and servos |
| SSLR_2.2 | Software Integration | Demonstration | Successful integration between microcontroller and Control Software |
The pass-fail criteria for the test plan are for the test stand are in the verification criteria.
| SSLR ID | Pass |
|---|---|
| SSLR_4.1 | The TVC deflection is within 1 degree of Avionics command. |
| SSLR_4.2 | The servos are able to receive commands from the avionics. |
| SSLR_3.3 | The Control Mechanisms receive commands from the Control Software |
| SSLR_2.1 | The microcontroller operates a servo motor in both forward and reverse directions |
| SSLR_2.2 | Operation of the overall system is demonstrated |
Process Table:
| # | Step Description | SSLR Verified | Check | Initials |
|---|---|---|---|---|
| 1 | Connect TVC to Avionics | |||
| 2 | Load TVC Calibration code onto Avionics Microcontroller | |||
| 3 | Make sure servos are connected correctly by doing a test movement in each axis | |||
| 4 | In each axis move the TVC from 1 to 8 degrees in 1 degree increments; taking a measurement each time |