Design: Select electronic components

[pjkirby31]

Obtain list of components per category:

1. IMU / barometer - Seif

2. Microcontroller / Servo - Patrick

3. Battery / Stepper - Brendan

IMU/Barometer considerations:

High accelerometer, magnetometer resolutions High sample rate (frequency of updates we can read)

Microcontroller:

I2C enabled or three SPI devices, and one UART device General purpose OS to run Python and C++ Breadboardable I/O (so it can fit onto a shield)

Servo/Stepper:

Self-locking axle Easy to mount via screw Max 8 wires 1-3˚ precision 1+ kg-cm torque Operates between 6-12 V Stall current less than 4A

Battery:

Slim form (fits within 2" height and 1" wide, length along board is less constrained) Supports idle servo/stepper for a minimum of 2 hours

[pjkirby31]

Sensors we could use:

• Raspberry Pi Zero W
  • I2C enabled, UART, and breadboardable (according to google)
  • Wifi enabled so we can connect to it wirelessly
  • C/C++ are supported natively, same with Python...or rust...
  • Cost: $34.50 for budget pack
• Arduino Uno
  • I2C enabled, UART, and breadboardable (according to google)
  • Apparently you can connect to an Arduino Uno over wifi, I didn't know that
  • C/C++ are supported natively, and could use MicroPython (subset of Python for Arduino)
  • Cost: $27.60 for board, I also have one we could use

Honestly I think both of these board would work well for our needs, I think the main difference is convenience. I think that a Raspberry Pi would be more better for the software side since it supports C++ and Python. It would also be very easy to store and maybe even generate VLTs with the Pi. Also using the wifi on the Pi to connect to it via ssh for development and in the field is just a nice feature to have. The Arduino might have similar capabilities with it's wifi card, but I'm not sure. However, I think the Arduino Uno would be more convenient for hardware. Since we are using inputs from multiple sensors and controlling a motor based on those values, the Arduino might be better suited for our purpose (that's what the internet says). The only reason why I say the Arduino isn't as good for software development is because I think writing code in C++ is much harder than Python, but that's just my opinion.

[elkhashabs]

https://www.amazon.com/BerryIMUv2-10DOF-Accelerometer-Gyroscope-Magnetometer-Barometric/dp/B072MN8ZRC/ref=sr_1_4?crid=JOP7OAFRBN30&keywords=imu+with+altimeter&qid=1690938272&sprefix=imu+with+altimeter%2Caps%2C111&sr=8-4

BerryIMUv3-10DOF - an Accelerometer, Gyroscope, Magnetometer and Barometric/Altitude Sensor

This seems like a good option: 6.7KHz (6,664 times a second!)

BerryIMUv3 is an inertial measurement unit, or IMU, that measures and reports on velocity, orientation and gravitational forces, using a combination of an accelerometer, gyroscope, and a magnetometer. BerryIMUv3 is also fitted with a barometric sensor (BMP388) which can be used to calculate altitude. A temperature sensor is also included.

IMUs can be found in devices like: quad copters, smart phones, segways, Wii remote, etc.. and are used to sense movement and orientation. BerryIMUv3 is compatible will all models of Raspberry Pi It is also compatible with Arduino, Teensy, ESP8266. Both 3.3V and 5V are supported. (We have included logic level shifters for 5V use)

Technical specifications: i2c and SPI interface Weight = 5gm IMU sensor LSM6DSL & LIS3MDL

Gyroscope: Measurement range:±125/±250/±500/±1000/±2000 dps

Accelerometer:

Scales of ±2g / ±4g / ±8g / ±16g

Magnetometer: Magnetic field full scale of ±4 / ±8 / ±12 / ±16 gauss. Internal temperature sensor Barometric Sensor BMP388 Pressure range: 300...1250 hPa @ 25°C 950...1050 hPa ±0.12 hPa, ±0.1m Temperature range: -40...+85 °C

BerryIMUv3 comes with: BerryIMU PCB with sensors 1x male header

[breadnmkii]

Makes sense to have both alt+imu, can have redundant sensors pretty easily