![](/media/cache/group/default_image.jpg.50x50_q85.jpg)
control for robotic arm that can play chess using a granular gripper
Dependencies: Encoder mbed HIDScope Servo MODSERIAL
Fork of chessRobot by
actuators.cpp
- Committer:
- annesteenbeek
- Date:
- 2015-10-20
- Revision:
- 89:9063484e8a1b
- Parent:
- 88:dd198c58f053
- Child:
- 94:28e274481b60
File content as of revision 89:9063484e8a1b:
#include "actuators.h" #include "PID.h" #include "mbed.h" #include "config.h" #include "encoder.h" #include "HIDScope.h" #include "Servo.h" // functions for controlling the motors bool motorsEnable = false; bool safetyOn = true; // start with safety off for calibration double encoder1Counts = 0; double encoder2Counts = 0; bool direction1 = false; // CCW is false(positive rotation), CW is true (neg rotation) bool direction2 = false; double motor1Pos = 0; double motor2Pos = 0; double motor1Speed = 0; double motor2Speed = 0; double motor1SetSpeed = 0; double motor2SetSpeed = 0; double servoPos = 0; double motor1PWM = 0; double motor2PWM = 0; // Set PID values double Kp1 = 1; double Ki1 = 0; double Kd1 = 0; double Kp2 = 0.008; double Ki2 = 0.08; double Kd2 = 0; double motor1PrevCounts = 0; double motor2PrevCounts = 0; double prevTime = 0; double now = 0; double timechange; bool pidOut = 0; // Create object instances // Safety Pin DigitalIn safetyIn(safetyPin); // Initialze motors PwmOut motor1(motor1PWMPin); PwmOut motor2(motor2PWMPin); // Initialize encoders Encoder encoder1(enc1A, enc1B); Encoder encoder2(enc2A, enc2B); // Set direction pins DigitalOut motor1Dir(motor1DirPin); DigitalOut motor2Dir(motor2DirPin); // create PID instances PID motor1PID(&motor1Speed, &motor1PWM, &motor1SetSpeed, Kp1, Ki1, Kd1); PID motor2PID(&motor2Speed, &motor2PWM, &motor2SetSpeed, Kp2, Ki2, Kd2); Servo servo(servoPin); Timer t; void motorInit(){ motor1Dir.write(direction1); motor2Dir.write(direction2); // Set motor PWM period motor1.period(1/pwm_frequency); motor2.period(1/pwm_frequency); motor1PID.SetSampleTime(motorCall); motor2PID.SetSampleTime(motorCall); motor1PID.SetOutputLimits(0,1); motor2PID.SetOutputLimits(0,1); // Turn PID on motor1PID.SetMode(AUTOMATIC); motor2PID.SetMode(AUTOMATIC); // start the timer t.start(); } void motorControl(){ // get encoder positions in degrees // 131.25:1 gear ratio // getPosition uses X2 configuration, so 32 counts per revolution // encoder reads CCW negative, and CW positive, so multiply by -1 to make CCW positive encoder1Counts = encoder1.getPosition(); encoder2Counts = encoder2.getPosition(); motor1Pos = -((encoder1Counts/32)/131.25)*360; motor2Pos = -((encoder2Counts/32)/131.25)*360; // check if motor's are within rotational boundarys // get encoder speeds in deg/sec now = t.read(); timechange = (now - prevTime); motor1Speed = -((((encoder1Counts - motor1PrevCounts)/32)/131.25)*360)/timechange; motor2Speed = -((((encoder2Counts - motor2PrevCounts)/32)/131.25)*360)/timechange; prevTime = now; motor1PrevCounts = encoder1Counts; motor2PrevCounts = encoder2Counts; // calculate motor setpoint speed in deg/sec from setpoint x/y speed if(motorsEnable){ // only run motors if switch is enabled // compute new PID parameters using setpoint angle speeds and encoder speed writeMotors(); }else{ // write 0 to motors motor1.write(0); motor2.write(0); } } void writeMotors(){ motor1PID.Compute(); // calculate PID outputs, output changes automatically motor2PID.Compute(); // write new values to motor's if (motor1SetSpeed > 0 ){ // CCW rotation direction1 = false; motor1PID.SetOutputLimits(0,1); // change pid output direction }else{ direction1 = true; // CW rotation motor1PID.SetOutputLimits(-1,0); } if (motor2SetSpeed > 0 ){ // CCW rotation direction2 = false; motor2PID.SetOutputLimits(0,1); }else{ direction2 = true; // CW rotation motor2PID.SetOutputLimits(-1,0); } motor1Dir.write(direction1); motor2Dir.write(direction2); motor1.write(abs(motor1PWM)); motor2.write(abs(motor2PWM)); } void servoControl(){ // use potMeter Value to set servo angle if (motorsEnable){ servo.write(servoPos); } // (optionaly calculate xy position to keep balloon in position) // calculate z position using angle // calculate x y translation of endpoint // find new x and y speed. } void calibrateMotors(){ safetyOn = false; bool calibrating1 = true; bool calibrating2 = true; double motorCalSpeed = 10; // deg/sec while (calibrating1 || calibrating2){ if (calibrating1){ motor1SetSpeed = motorCalSpeed; // deg/sec if(safetyIn.read() !=1){ // check if arm reached safety position calibrating1 = false; // done motor1SetSpeed = 0; // brake motor encoder1.setPosition(0); // set motor 1 cal angle // move away } } if (calibrating1){ motor2SetSpeed = motorCalSpeed; // deg/sec if(safetyIn.read() !=1){ // check if arm reached safety position calibrating2 = false; // done motor2SetSpeed = 0; // brake motor encoder2.setPosition(0); // set motor 2 cal angle // move away } } writeMotors(); wait(0.01f); } safetyOn = true; // turn safety on after callibration } void safety(){ if (safetyOn){ if (safetyIn.read() != 1){ motorsEnable = false; } } }