Robot on Python

Robot implementation using RobotPy. Start here.

In short:

1. On Windows, install Visual Studio 2019 redistributable. If you are set up to do FRC stuff then this is likely already installed.
2. py -m pip install robotpy[all] This should install RobotPy and pretty much every dependency including optional ones like cscore, REV, PhotonVision and more.
3. py robot.py sim would run the code in simulator mode, though without a finished physics.py that won't work.
4. py robot.py test would run our automated tests, if we have any. (We don't yet.)
5. py robot.py deploy would run the code on the robot, provided someone has already installed RobotPy 2023. Add the --nc option to see console output directly rather than having to open a separate NetConsole window (whatever that is). If we have any automated tests that are failing (since deploy runs them automatically), add --skip-tests.
6. If you want the code to run at robot boot time, see this link.

Note that none of this installs RobotPy on the robot itself. To do that follow Robot Installation and note also that unless you use robotpy_installer install robotpy[all] you will have to install various third-party vendor packages separately. For example if you need import rev you'll want to do robotpy_install install robotpy[rev] and so on. See also Package notes.

API Basics

Joysticks

Joystick axis readings range between -1.0 and 1.0. Generally forward is Y negative, backward is Y positive. Left is X negative, right is X positive. Joysticks may have a twist axis, or others e.g. a throttle or a sensitivity axis.

The axes are associated with channels, which can be queried or set. The defaults are e.g. kDefaultThrottleChannel.

Buttons include a trigger button (usually index finger), a "top" button (thumb), and possibly many others.

The API provides routines to read the current state, e.g. getTop() and also some stateful values such as getTopPressed() or getTopReleased() which apparently return True only once, when first called following the pressing or releasing of the button.

The wpilib.DriverStation API provides a few things to query the currently attached controllers. Note that it appears that attaching a joystick while the code is running may not be visible without a restart, at least based on running in the simulator.

• DS.isJoystickAttached(n)
• DS.getJoystickName(n) e.g. 'Logitech Extreme 3D' or 'Keyboard 0'
• DS.getJoystickType(n) is useful in theory but in the sim at least returns 0 for everything.
• DS.getLocation() returns 1, 2, 3 for position of driver station in the field.
• DS.getAlliance() returns DS.Alliance.kRed/kBlue/kInvalid (0/1/2)
• DS.getMatchTime() may be useful in helping control end-of-period autonomous routines, possibly cutting them short if there's not enough time for a fancier version... Note that it's documented as being not guaranteed to be accurate so there may be a better way to do this.
• DS.getStickAxisCount(n) returns a count, 3 for sim keyboard, 4 for Logitech 3D
• DS.getStickButtonCount() also works, 4 for sim kb, 12 for L3D
• DS.isDSAttached() may be useful, though note that it's True for the sim as well (though sim can toggle it). Presumably most useful in judging whether these other APIs are going to return useful data, and maybe ones like the wpilib.Joystick and similar controller stuff.

DigitalInputs

di = wpilib.DigitalInput(n) gets a channel 0-9 (on the RIO) or 10-25 (MXP).

di.get() returns boolean with current state.

Simulation: setSimDevice(n) ... not sure how the interface with simulated stuff works yet.