Create the UltraSonic component interface for use in the robot.py framework.

[mcolinj]

Look at the Freenove example code for a sonar unit, and move the function into a UltraSonic class so that it can be used. Refer to the wpilib UltraSonic interface so we can keep it compatible.

[EmilyRobotics]

Looks like the built in ultrasonic sensor class has three main functions: send_trigger_pulse() wait_for_echo get_distance

To make a wpilib-compatable version, you will have to: add a unit converter funciton, giving output in inches or mm create a new counter program similar in function to the combination of send_trigger_pulse and wait_for_echo and add the rest of the wpilib functions (should be pretty simple) to make it fully compatable

Might want to consider making a base sensor class, similar to the one wpilib has to make things easier when/if we get new sensors from electrical

see Ultrasonic.py in the freenove code, wpilib documentation, and [wpilib code](https://github.com/robotpy/robotpy-wpilib/blob/2019/wpilib/wpilib/ultrasonic.py

[EmilyRobotics]

Then for the camera motor, you should probably put that in its own seperate class

[mcolinj]

Camera motor should be an instance of the Servo class. There is probably a reason to combine the two servos into something like a tilt/pan object. But we don't have much control of the servos, and don't know where they are, so as an assembly, it would have limited capabilities.

[mcolinj]

This job might look intimidating at first, but you can work on it in stages.

1. Look at the Freenove code and see how the Ultrasonic interface works. https://github.com/Freenove/Freenove_4WD_Smart_Car_Kit_for_Raspberry_Pi/tree/master/Code/Server

2. Manually run it, maybe surround it with a loop that reports range values to convince yourself that it does work. You don't have to have the tilt/pan assembled for this. You can just plug in the sonar unit and set it on the robot platform or another holder. Or if you just have a Raspberry Pi and a sonar unit, you can wire them up for testing.

3. Then think about how you could package it up so it looks more like the UltraSonic interface in wpilib.

[sorenfnt]

I hope someone else worked on this issue today, cause I sure didn't!

[sorenfnt]

https://github.com/Freenove/Freenove_4WD_Smart_Car_Kit_for_Raspberry_Pi/blob/master/Code/Server/Ultrasonic.py The link to the existing sensor code from Freenove

[sorenfnt]

It looks like the Freenove code handles getting the distance by sending 3 trigger pulses in quick succession and taking the middle value, a clever internal data smoothing. We may or may not want to adopt this either as data smoothing or in addition to computing a rolling average/throwing out bad values.