An embedded robotics project using C# and the Nvidia Xavier NX.

Relies on AV00-Transport for inter-service communication.

• It is too easy to configure the wrong engine on the wrong channel and have bad things happen. I need to find a way to make this more robust. Example: I had the motors swapped and the wrong motor was using the wrong software constraints (Move used Turn softCaps and nearly blew the power source).

• Create a desktop application to view telemery over WIFI. - Halted for now due to this issue xamarin/Xamarin.Forms#10818

• Update the DeviceRegistry to be useful.
• Add the MotorController/DriveService to the ServiceRegistry
• Create a telemetry service for the robot.
• Add an ultrasonic sensor to the robot.
• Create a basic feedback loop the stops the motors near an obstacle.
• Add a gyro sensor to the robot.
• Create a basic feedback loop that keeps the robot driving straight.
• Implement a strategy for handling blocking, non-blocking, and override motor operations.

AV00 Shared

• Debating moving all the hardware drivers into a separate repo as they might benefit other programers.

AV00 Transport

• Create a transport layer to allow services to communicate with each other.

AV00 Control Application Repo

• Halted for now due to this issue xamarin/Xamarin.Forms#10818

• Implement backing DB for storing event stream and powering UI.

• Display current events as they happen.

• Allow filtering of events.

• Remote input/override client.

• Setup a CI/CD pipeline.
• Dockerize the application to run in NV containers.

• Add an ultrasonic sensor to the robot.
• Add a gyro sensor to the robot.
• Run some updated battery driven tests.

• Update documentation.
• Update design docs.
• Update spec sheets.

• Make the MotorController public functions async to allow non-blocking timed operations.
• M3/4 mounts inside the chassis.
• Remote input/override service.
• Create a basic console status screen while running program from terminal.

• Digital Port: IO expansion board offers 28 groups (D0-D27) of digital ports that are led out via Raspberry Pi ports GPIO0~GPIO27 (BCM codes)
• Requires libgpiod-dev (Could not get to work on JP4)
• sudo apt install -y libgpiod-dev
• gpiochip1 [tegra-gpio-aon] (40 lines)
• Gpiod uses line numbers to access gpio. The line numbers can be found with gpioinfo and cross referenced with the nvidia pinmux spreadsheet.
• The pinmux spreadsheet can be found here: https://developer.nvidia.com/jetson-nano-pinmux-datasheet
• Notes for personal use, these are free GPIO pins.
  • gpiochip1 127 -- BCM 17 -- J41 Pin 11
  • gpiochip1 112 -- BCM 18 -- J41 Pin 12
• PWM2 on MD10A is driver motor, PWM1 is turning motor
• XavierNX built-in PWMs are not strong enough to hold a signal for motors even with external motor power supply. Would always drop below 2v.
• Requires PCA9685 or STM32 equivalent to drive motors.

• https://github.com/dotnet/iot/blob/main/src/System.Device.Gpio/System/Device/I2c/I2cDevice.cs#L11
• https://developer.download.nvidia.com/assets/embedded/secure/jetson/xavier/docs/Xavier_TRM_DP09253002.pdf?VakqmUGBQ99wvpu9mQgUOnm_mwq8MupZBel1lXFho98PGkC6gCjYKa58bYSGYUZZYHMpkF-PPS9WNeV_KmsmQxUQX84dYaEQavkufeAuom2ZpN2P8oQ3I1gSljfF-7rzC1sxKAXvgDnQlzdmma_jvCdqtjyKvye5MFmhFtSSG63Huw==&t=eyJscyI6ImdzZW8iLCJsc2QiOiJodHRwczovL3d3dy5nb29nbGUuY29tLyJ9
• https://github.com/NVIDIA/jetson-gpio/blob/6cab53dc80f8f5ecd6257d90dc7c0c51cb5348a7/lib/python/Jetson/GPIO/gpio_pin_data.py#L321
• https://forums.developer.nvidia.com/t/gpio-numbers-and-sysfs-names-changed-in-jetpack-5-linux-5-10/218580/7
• https://forums.developer.nvidia.com/t/gpio-numbers-and-sysfs-names-changed-in-jetpack-5-linux-5-10/218580/3
• https://jetsonhacks.com/nvidia-jetson-xavier-nx-gpio-header-pinout/