Mogball / communication-system

NodeJS WebSocket/Serial converter on the RPi, to link the Arduino to frontend and store it in a "black box"

For the system to work, both the RPI and user laptop has to be located on the same network. Plug in the router into a wall outlet and connect to the network called dd-wrt

Setup instructions Server

• Clone the repo
• Navigate to /server
• Run npm install (make sure you have a working internet connection)
• Run node server.js to run the server

Notes:

• Server automatically save all of the records from every launch when all the clients disconnect, or
• Force save by typing save while the server is running
  • The records from every launch are stored in server/launch-records/timestamp.json
• Additionally, the server logs all of the incoming commands
  • The log file is stored in server/blackgox.log

Setup instructions Client

• Clone the repo
• Navigate to /client
• Run npm install (make sure you have a working internet connection)
• Run node client.js to run the server

CLI commands

cmd	description
'ping'	run connection test
'connect'	command to initiate arduino creates connection between RPI and Arduino
'data stop'	start writing raw data to a file on pi
'data start'	stop writing raw data to a file on pi
'data save'	manually save raw out file
'bv on'	turn ball valve on
'bv off'	turn ball valve off
'dpr on'	turn dpr on
'dpr off'	turn dpr off
'drive on'	turn emergency drive on
'drive off'	turn emergency drive off
'drop on'	turn emergency wheel release on
'drop off'	turn emergency wheel release off
'auto on'	enable autonomous mode
'man on'	enable manual mode
'start script'	run off script
'ar rests'	restart arduino and save states
'ar restus'	restart arduino and reset states
'brake on'	turn brake on
'brake off'	turn brake off
'emg on'	turn on emergency mode
'emg off'	turn off emergency mode
'speed --50'	set speed (ex: to set speed to 50%, enter 'speed --50')

Communication format

• Only certain commands and certain types of data is sent through the communication pipeline
• Find information about it here

IO data structure used in NAV.py:

• All heartbeat data are preserved throughout the processing

• svr_process_monotype(json_arr, d_type) does preliminary error correction on the input stream. Disabling this function will NOT affect other computations.

• calc_lat_force(accel_arr) takes an array of accelerometer data and calculates the force applied to the pod in x,y, and z directions. Return array has time in seconds and force in Newtons assuming 140kg for the weight of the pod.

• calc_lin_velocity(accel_arr) takes an array of accelerometer data and outputs acceleration in m/s^2. Return array has time in seconds and sensor type "lvel"

• calc_lin_displacement(prev_disp, vel) takes an array of previously computed displacements and velocities calculated in calc_lin_velocity(). The function outputs displacement in meters and time in seconds. Sensor type = "ldisp"

• out_row_pitch_yaw() should be disabled in the python script and directly computed on the arduino since yaw would require two input streams with synchronized time stamps.

• calc_ang_velocity(gyro_arr) outputs angular velocitiy in radians per second. The kvp for 'sensor' : sensor_type is unchanged.

• optical(opt_json, prev_stats, counter) takes in an array of optical sensor data in json format (which will come from RPi), an array of previously computed data, and a counter (both of which will be stored in the script). prev_stats has the format [time, displacement, velocity] and will be printed to stdout at the end of the main function call.