#Robotc encoder code#

It seems to me the concepts set out by the RobotC code offers the perfect solution. I have spent many hours on trying to come up with a way to get the bot to travel in a straight line using some aspect of PID that is not overly complex for this relatively simple task. It uses integers only and math that does not result in floats. If the motors moved at exactly the same speed, this value would be 0.ДЄnother important aspect of the RobotC straight line code is it does not use floats or other data types that consume large amounts of microprocessor resources. Negative if slave has to slow down, positive if it has to speed up. My limited programming experience/skills do not allow me to simply translate RobotC to an Arduino sketch C which I am currently learning.ДЄs explained at the above web page the difference between the master encoder and the slave encoder ticks can be used to determine error. This concept was presented at the web page below which uses RobotC for programming. In this situation Error = speed_Master - speed_Slave However, as expected, the bot cannot travel in straight line.Д¬oncept: Keep it simple by having one motor serve as the speed master and the other as a speed slave, where the master motor speed is held constant and the slave motor speed is varied so as to match the master motor speed. Great precision is not needed for this challenge therefore, limited tracking (drift) back and forth across the straight line path is acceptable.Д¬urrent situation: The bot has been tested and it goes forward, backwards, turns etc.

#Robotc encoder how to#

Hobbyist Situation: Good hardware/electronics skills, just learning how to program.Д¬hallenge: Creating a sketch that will allow the bot to travel in a straight line for some distance, turnaround and travel back to the start point. Now you can rotate the mechanism forward and stop the motor when the Encoder COUNT reaches a particular value.Project: Arduino robot with Pololu motors equipped with hall effect quadrature encoders. Rotate your mechanism backward using PWM value until the home limit switch closes, then reset the Encoder COUNT to zero. If you want your motor to move an arm to a particular position, use the encoder count and a home limit switch connected to a Digital Input. Only one output channel (wire) is needed to transmit the sensor data to the Vex Microcontroller. Problems arise if your encoder fails or one of the Digital Input wires fall off вЂ¦ your control loop sees the encoder count NOT CHANGING and assumes the motor is not moving вЂ¦ when in actuality your robot wheel is turning at max speed and the 'bot is spinning in a circle Often a PID Control Loop is used for this. If you want your motors to run at a particular speed, adjust the PWM output up or down depending on whether the Speed is too slow or too fast. Speed MINUS previous Speed = acceleration (ticks)

#Robotc encoder software#

If you want to calculate speed using encoders, your software loop should run at a fixed frequency - say once every 50 msec (or - the standard 18.2 msec, if you prefer).Дistance MINUS previous Distance = speed (ticks) Easењњ has a nice Quad Encoder function, you just tell it which digital inputs you are using and it counts the pulses for you - use the same function to read the current count value, which increases with forward motion of the encoder, decreases with reverse motion.

The Potentiometer needs to be paired with a programming. The encoders have two output signal wires (plus ground and 5 volts) which are connected to two Digital Inputs on the Robot Controller. This is unlike the Optical shaft encoder which loses its reading every time the Brain is powered down. Now, having said that, if you want to get higher performance of motor control, such as eliminate overshooting, you will need to use the encoder to tell the maximum distance (equivalent to the encoder value, you need simple gear math work here, of course). Quad encoders provide direction of rotation, whereas the geartooth sensors in the KOP do not. You do not use encoders to control speed. We use Grayhill 61K128 quadrature encoders, for wheels and anything else that needs position or speed information. Useful Resource Links RobotC basic User Interface Overview Getting Started With RobotC for VEX Programming with the new VEX Motor Encoders RobotC VEX.