CANTalon Python Help

[StrMNX]

So i'm trying to run a CANTalon at some RPM. i decided on PIDF control. i chose 1366 RPM because its the speed done in the Software Reference Manual. i've tried to convert the java code into python, but the shooter refuses to run. can anyone help me?

#!/usr/bin/env python3

import wpilib
import ctre
from networktables import NetworkTable

class MyRobot(wpilib.IterativeRobot):
    
    def robotInit(self):
        self.Shooter = ctre.CANTalon(1)
        self.Shooter.reverseOutput(False)
        
        self.Shooter.setFeedbackDevice(ctre.CANTalon.FeedbackDevice.CtreMagEncoder_Relative)
        
        self.Shooter.configNominalOutputVoltage(float(+0.0), float(-0.0))
        self.Shooter.configPeakOutputVoltage(float(+12.0), float(-12.0))
        
        self.Shooter.setProfile(0)
        self.Shooter.setF(0.1097)
        self.Shooter.setP(0)
        self.Shooter.setI(0)
        self.Shooter.setD(0)
        
        self.Shooter.changeControlMode(ctre.CANTalon.ControlMode.Speed)
        self.xb = wpilib.Joystick(2)
        
    
        
        self.sd = NetworkTable.getTable('SmartDashboard')
    def teleopPeriodic(self):
        
        self.sd.putNumber("Velocity", self.Shooter.getSpeed())
        if(self.xb.getRawButton(5)):
            self.Shooter.set(1366)
            
        else:
            self.Shooter.set(0)

if __name__ == "__main__":
    wpilib.run(MyRobot)

[virtuald]

Originally Posted by StrMNX

So i'm trying to run a CANTalon at some RPM. i decided on PIDF control. i chose 1366 RPM because its the speed done in the Software Reference Manual. i've tried to convert the java code into python, but the shooter refuses to run. can anyone help me?

#!/usr/bin/env python3

import wpilib
import ctre
from networktables import NetworkTable

class MyRobot(wpilib.IterativeRobot):
    
    def robotInit(self):
        self.Shooter = ctre.CANTalon(1)
        self.Shooter.reverseOutput(False)
        
        self.Shooter.setFeedbackDevice(ctre.CANTalon.FeedbackDevice.CtreMagEncoder_Relative)
        
        self.Shooter.configNominalOutputVoltage(float(+0.0), float(-0.0))
        self.Shooter.configPeakOutputVoltage(float(+12.0), float(-12.0))
        
        self.Shooter.setProfile(0)
        self.Shooter.setF(0.1097)
        self.Shooter.setP(0)
        self.Shooter.setI(0)
        self.Shooter.setD(0)
        
        self.Shooter.changeControlMode(ctre.CANTalon.ControlMode.Speed)
        self.xb = wpilib.Joystick(2)
        
    
        
        self.sd = NetworkTable.getTable('SmartDashboard')
    def teleopPeriodic(self):
        
        self.sd.putNumber("Velocity", self.Shooter.getSpeed())
        if(self.xb.getRawButton(5)):
            self.Shooter.set(1366)
            
        else:
            self.Shooter.set(0)

if __name__ == "__main__":
    wpilib.run(MyRobot)

Have you started with just a simple example, making sure that when you tell the motor to move it moves? Or did you start with this?

[StrMNX]

Originally Posted by virtuald

Have you started with just a simple example, making sure that when you tell the motor to move it moves? Or did you start with this?

Yeah, it was tested and runs.
It works when I disable the speed change mode and run it on Normal .set(1) for percentage. But when I enable the speed change mode and set it to 1366 it won't run. Plus even with the .set(1), getSpeed() always returns 0.

[virtuald]

I know last year we used the speed mode and it worked.

One difference between your code and theirs is that they set P to something: https://github.com/CrossTheRoadElec/...Robot.java#L46

[StrMNX]

Originally Posted by virtuald

I know last year we used the speed mode and it worked.

One difference between your code and theirs is that they set P to something: https://github.com/CrossTheRoadElec/...Robot.java#L46

after running it with some P value it works
but the getSpeed() command simply returns 0.
any reason why that would be?

[StrMNX]

Originally Posted by StrMNX

after running it with some P value it works
but the getSpeed() command simply returns 0.
any reason why that would be?

so i've tried both sending the getSpeed() value to smartdashboard and having them printed out in the console, and either one report 0 while the roborio dashboard reports a RPM value. any way i can resolve this?

[virtuald]

Originally Posted by StrMNX

so i've tried both sending the getSpeed() value to smartdashboard and having them printed out in the console, and either one report 0 while the roborio dashboard reports a RPM value. any way i can resolve this?

The RoboRIO dashboard? You mean in the self-test thing?

There's one more difference in their code and your code: You call reverseOutput, they call reverseSensor. Might make a difference?

Are you using the MagEncoder, or a different sensor?

Unfortunately, I don't own the hardware for this device, so I can't perform a test. I'm fairly certain getSpeed worked last year though. What does .get() return? Also, you might try seeing what getEncVelocity() returns.

[virtuald]

Also, have you upgraded to RobotPy 2017.0.6? There was a bug in prior versions that could cause weird issues because HAL was initialized twice.

[StrMNX]

Originally Posted by virtuald

Also, have you upgraded to RobotPy 2017.0.6? There was a bug in prior versions that could cause weird issues because HAL was initialized twice.

i did not update to 2017.0.6
i will have to on the next meeting. and i'll play around with the code to see what else i can get. the RPM was in the self test function fine. i was using a TalonSRX wired up over the CANBus with a CTRE mag encoder hooked up to the Talon.