[FTC]: FTC Encoder Program with Distance

[FRC Team CC]

Hello,

We are trying to program our Autonomous portion using distance with
TETRIX DC Motor encoders. The following is our program:

#pragma config(Hubs,  S1, HTMotor,  HTMotor,  HTServo,  HTMotor)
#pragma config(Motor,  mtr_S1_C1_2,     leftBottomDrive, tmotorTetrix, openLoop, encoder)
#pragma config(Motor,  mtr_S1_C4_1,     rightBottomDrive, tmotorTetrix, openLoop, reversed, encoder)

//*!!Code automatically generated by 'ROBOTC' configuration wizard               !!*//

task main()
{
	float diameterOfWheel = 3.96;//set the diameter of wheel to 3.96 inches
	float circumfirence = diameterOfWheel*PI;
	
	int distanceToGo = 12;//we want the robot to go one foot, or 12 inches
	float rotations = distanceToGo/circumfirence;
	int degreesToTurn = rotations*360;
	int encoderCounts = degreesToTurn*4;//encoder counts are in quarter degrees, so 4 encoder counts = 1 degree
	
	nMotorEncoder[leftBottomDrive] = 0;//motors do not run
	nMotorEncoder[rightBottomDrive] = 0;
	
	nMotorEncoderTarget[leftBottomDrive] = encoderCounts;//tell motors to go a foot
	nMotorEncoderTarget[rightBottomDrive] = encoderCounts;
	motor[leftBottomDrive] = 50;//go at power 50
	motor[rightBottomDrive] = 50;
	
	while(nMotorRunState[leftBottomDrive] != runStateIdle)
	{
		
	}
	motor[leftBottomDrive] = 0;//turn motors off
	motor[rightBottomDrive] = 0;
}

When testing the program, the motors drove unlimited instead of stopping after one foot.

Regards,

The Charging Champions

[Sasha]

In pragma, change
#pragma config(Motor, mtr_S1_C1_2, leftBottomDrive, tmotorTetrix, openLoop, encoder)
to
#pragma config(Motor, mtr_S1_C1_2, leftBottomDrive, tmotorTetrix, PIDControl, encoder)

(or just check the box "PID control" in Motor and sensor setup). Obviously, you need to do this for both motors.

[FRC Team CC]

Sorry, we forgot to mention that we tried this. It worked on the right wheel, but on the left wheel, it was jerking around and did not move as smoothly.

Is this a building error or a wiring error?

Thanks,
Charging Champions
FTC Team 8660

[Sasha]

I'd guess a building error, but can't say without seeing the robot. Or maybe the encoder cable is damaged? if these are Tetrix motors, the encoder cable is very fragile.