Biorobotics / Robot-Software

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Dependencies:   HIDScope MODSERIAL QEI biquadFilter mbed Servo

main.cpp@15:7d3b138446fa, 2018-10-25 (annotated)

Committer:
SvenD97
Date:
Thu Oct 25 08:51:32 2018 +0000
Branch:
bla
Revision:
15:7d3b138446fa
Parent:
14:4744cc6c90f4
Child:
16:0280a604cf7e
Included motor encoder;

Who changed what in which revision?

UserRevisionLine numberNew contents of line
MaikOvermars 0:4cb1de41d049 1 #include "mbed.h"
MaikOvermars 0:4cb1de41d049 2 #include "MODSERIAL.h"
MaikOvermars 0:4cb1de41d049 3 #include "QEI.h"
MaikOvermars 0:4cb1de41d049 4 #include "HIDScope.h"
MaikOvermars 0:4cb1de41d049 5 #include "BiQuad.h"
MaikOvermars 0:4cb1de41d049 6 #include "PID_controller.h"
MaikOvermars 0:4cb1de41d049 7 #include "kinematics.h"
MaikOvermars 0:4cb1de41d049 8
MaikOvermars 0:4cb1de41d049 9 //Define objects
MaikOvermars 0:4cb1de41d049 10 MODSERIAL pc(USBTX, USBRX);
MaikOvermars 0:4cb1de41d049 11 HIDScope scope(2);
MaikOvermars 0:4cb1de41d049 12
MaikOvermars 10:7339dca7d604 13 // emg inputs
MaikOvermars 0:4cb1de41d049 14 AnalogIn emg0( A0 );
MaikOvermars 0:4cb1de41d049 15 AnalogIn emg1( A1 );
MaikOvermars 0:4cb1de41d049 16
MaikOvermars 10:7339dca7d604 17 // motor ouptuts
MaikOvermars 0:4cb1de41d049 18 PwmOut motor1_pwm(D5);
MaikOvermars 0:4cb1de41d049 19 DigitalOut motor1_dir(D4);
MaikOvermars 0:4cb1de41d049 20 PwmOut motor2_pwm(D7);
MaikOvermars 0:4cb1de41d049 21 DigitalOut motor2_dir(D6);
MaikOvermars 0:4cb1de41d049 22
SvenD97 14:4744cc6c90f4 23 // defining encoders
SvenD97 15:7d3b138446fa 24 QEI motor_1_encoder(D12,D13,32);
SvenD97 15:7d3b138446fa 25 QEI motor_2_encoder(D10,D11,32);
SvenD97 14:4744cc6c90f4 26
MaikOvermars 0:4cb1de41d049 27 AnalogIn potmeter1(A2);
MaikOvermars 0:4cb1de41d049 28 AnalogIn potmeter2(A3);
MaikOvermars 0:4cb1de41d049 29 DigitalIn button(D0);
MaikOvermars 0:4cb1de41d049 30
SvenD97 14:4744cc6c90f4 31 // tickers and timers
MaikOvermars 0:4cb1de41d049 32 Ticker Sample;
MaikOvermars 0:4cb1de41d049 33 Timer state_timer;
MaikOvermars 0:4cb1de41d049 34
MaikOvermars 0:4cb1de41d049 35 enum States {failure, waiting, calib_enc, calib_emg, operational, demo}; //All possible robot states
MaikOvermars 0:4cb1de41d049 36
MaikOvermars 0:4cb1de41d049 37 //Global variables/objects
MaikOvermars 0:4cb1de41d049 38 States current_state;
MaikOvermars 0:4cb1de41d049 39 Ticker loop_ticker; //The Ticker object that will ensure perfect timing of our looping code
SvenD97 14:4744cc6c90f4 40 double x,y, qref1, qref2 ,e, e1, e2, u1, u2, emg_signal_raw_0, processed_emg_0, emg_signal_raw_1, processed_emg_1, robot_end_point, reference_end_point, motor_angle, q1, q2, motor_1_counts, motor_2_counts; //will be set by the motor_controller function
MaikOvermars 0:4cb1de41d049 41 int counts_per_rotation = 32;
MaikOvermars 0:4cb1de41d049 42 bool state_changed = false;
MaikOvermars 10:7339dca7d604 43 double samplingfreq = 1000;
SvenD97 5:0dd66c757f24 44 double x; // Making the position (x,y) of the end effector global
SvenD97 5:0dd66c757f24 45 double y;
SvenD97 8:bba05e863b68 46 const double T = 0.001;
MaikOvermars 0:4cb1de41d049 47
MaikOvermars 0:4cb1de41d049 48 float processing_chain_emg(int num) {
MaikOvermars 0:4cb1de41d049 49 return 6.0;
MaikOvermars 0:4cb1de41d049 50 }
MaikOvermars 0:4cb1de41d049 51
MaikOvermars 0:4cb1de41d049 52 void measure_all()
MaikOvermars 0:4cb1de41d049 53 {
SvenD97 14:4744cc6c90f4 54 motor_1_counts = motor_1_encoder.getPulses();
SvenD97 14:4744cc6c90f4 55 motor_2_counts = motor_2_encoder.getPulses();
SvenD97 14:4744cc6c90f4 56 q1 = motor_1_counts*2.0f*3.1415926535f/counts_per_rotation; //do this here, and not in the encoder interrupt, to reduce computational load
SvenD97 14:4744cc6c90f4 57 q2 = motor_2_counts*2.0f*3.1415926535f/counts_per_rotation;
SvenD97 14:4744cc6c90f4 58 forwardkinematics_function(q1,q2,x,y); //motor_angle is global, this function ne
MaikOvermars 0:4cb1de41d049 59 emg_signal_raw_0 = emg0.read(); //sample analog voltages (all sampling theory applies, you might get aliasing etc.)
MaikOvermars 0:4cb1de41d049 60 emg_signal_raw_1 = emg1.read();
MaikOvermars 0:4cb1de41d049 61 processed_emg_0 = processing_chain_emg(0); // some function ‘float my_emg_processing_chain()’ that returns a float. The raw emg is global
MaikOvermars 0:4cb1de41d049 62 processed_emg_1 = processing_chain_emg(1);
MaikOvermars 0:4cb1de41d049 63 }
MaikOvermars 0:4cb1de41d049 64
MaikOvermars 0:4cb1de41d049 65 void output_all() {
MaikOvermars 0:4cb1de41d049 66 motor1_pwm = fabs(u1);
MaikOvermars 0:4cb1de41d049 67 motor1_dir = u1 > 0.5f;
MaikOvermars 0:4cb1de41d049 68 motor2_pwm = fabs(u2);
MaikOvermars 0:4cb1de41d049 69 motor2_dir = u2 > 0.5f;
MaikOvermars 0:4cb1de41d049 70 static int output_counter = 0;
MaikOvermars 0:4cb1de41d049 71 output_counter++;
MaikOvermars 0:4cb1de41d049 72 if (output_counter == 100) {pc.printf("Something something... %f",u1); output_counter = 0;} //Print to screen at 10 Hz with MODSERIAL
MaikOvermars 0:4cb1de41d049 73 }
MaikOvermars 0:4cb1de41d049 74
MaikOvermars 0:4cb1de41d049 75 void state_machine() {
MaikOvermars 0:4cb1de41d049 76 switch(current_state) { //States can be: failure, wait, calib_enc, calib_emg, operational, demo,
MaikOvermars 0:4cb1de41d049 77 case waiting: //Nothing useful here, maybe a blinking LED for fun and communication to the user
MaikOvermars 0:4cb1de41d049 78 if (button.read()==true)
MaikOvermars 0:4cb1de41d049 79 {
MaikOvermars 0:4cb1de41d049 80 current_state = calib_enc; //the NEXT loop we will be in calib_enc state
SvenD97 9:8e1112874c12 81 // no state_changed action?
MaikOvermars 0:4cb1de41d049 82 }
MaikOvermars 0:4cb1de41d049 83 break; //to avoid falling through to the next state, although this can sometimes be very useful.
MaikOvermars 0:4cb1de41d049 84
MaikOvermars 0:4cb1de41d049 85 case calib_enc:
MaikOvermars 0:4cb1de41d049 86 if (state_changed==true)
MaikOvermars 0:4cb1de41d049 87 {
MaikOvermars 0:4cb1de41d049 88 state_timer.reset();
MaikOvermars 0:4cb1de41d049 89 state_timer.start();
MaikOvermars 0:4cb1de41d049 90 state_changed = false;
MaikOvermars 0:4cb1de41d049 91 }
MaikOvermars 0:4cb1de41d049 92 u1 = 0.6f; //a low PWM value to move the motors slowly (0.0 to 0.45 don’t do much due to friction)
MaikOvermars 0:4cb1de41d049 93 // fabs(motor1.velocity()) < 0.1f &&
MaikOvermars 0:4cb1de41d049 94 if (state_timer.read() > 5.0f) {
MaikOvermars 0:4cb1de41d049 95 current_state = calib_emg; //the NEXT loop we will be in calib_emg state
MaikOvermars 0:4cb1de41d049 96 state_changed = true;
MaikOvermars 0:4cb1de41d049 97 }
MaikOvermars 0:4cb1de41d049 98 break;
MaikOvermars 0:4cb1de41d049 99
MaikOvermars 0:4cb1de41d049 100 case calib_emg: //calibrate emg-signals
MaikOvermars 0:4cb1de41d049 101
MaikOvermars 0:4cb1de41d049 102 break;
MaikOvermars 0:4cb1de41d049 103
MaikOvermars 0:4cb1de41d049 104 case operational: //interpreting emg-signals to move the end effector
MaikOvermars 0:4cb1de41d049 105 if (state_changed==true) { int x = 5; }
MaikOvermars 0:4cb1de41d049 106 // example
MaikOvermars 0:4cb1de41d049 107 reference_end_point = robot_end_point + processed_emg_0;
MaikOvermars 0:4cb1de41d049 108 if (button.read() == true) { current_state = demo; }
MaikOvermars 0:4cb1de41d049 109
MaikOvermars 0:4cb1de41d049 110 break;
MaikOvermars 0:4cb1de41d049 111
MaikOvermars 0:4cb1de41d049 112 case demo: //moving according to a specified trajectory
MaikOvermars 0:4cb1de41d049 113
MaikOvermars 0:4cb1de41d049 114 if (button.read() == true) { current_state = demo; }
MaikOvermars 0:4cb1de41d049 115
MaikOvermars 0:4cb1de41d049 116 break;
MaikOvermars 0:4cb1de41d049 117
MaikOvermars 0:4cb1de41d049 118 case failure: //no way to get out
MaikOvermars 0:4cb1de41d049 119 u1 = 0.0f;
MaikOvermars 0:4cb1de41d049 120 break;
MaikOvermars 0:4cb1de41d049 121 }
MaikOvermars 0:4cb1de41d049 122 }
MaikOvermars 0:4cb1de41d049 123
MaikOvermars 0:4cb1de41d049 124 void motor_controller()
MaikOvermars 0:4cb1de41d049 125 {
MaikOvermars 0:4cb1de41d049 126 if (current_state >= operational) { // we can (ab)use the fact that an enum is actually an integer, so math/logic rules still apply
MaikOvermars 10:7339dca7d604 127 q_ref += inversekinematics_function(reference_end_point)/samplingfreq; //many different states can modify your reference position, so just do the inverse kinematics once, here
MaikOvermars 10:7339dca7d604 128 e1 = q_ref - motor_angle; //tracking error (q_ref - q_meas)
MaikOvermars 10:7339dca7d604 129 e2 = q_ref - motor_angle;
MaikOvermars 10:7339dca7d604 130 PID_controller(e1,e2,u1,u2); //feedback controller or with possibly fancy controller additions...; pass by reference
MaikOvermars 0:4cb1de41d049 131 } //otherwise we just don’t mess with the value of control variable ‘u’ that is set somewhere in the state-machine.
MaikOvermars 0:4cb1de41d049 132 }
MaikOvermars 0:4cb1de41d049 133
MaikOvermars 0:4cb1de41d049 134
MaikOvermars 0:4cb1de41d049 135 void loop_function() {
MaikOvermars 0:4cb1de41d049 136 measure_all(); //measure all signals
MaikOvermars 0:4cb1de41d049 137 state_machine(); //Do relevant state dependent things
MaikOvermars 0:4cb1de41d049 138 motor_controller(); //Do not put different motor controllers in the states, because every state can re-use the same motor-controller!
MaikOvermars 0:4cb1de41d049 139 output_all(); //Output relevant signals, messages, screen outputs, LEDs etc.
MaikOvermars 0:4cb1de41d049 140 }
MaikOvermars 0:4cb1de41d049 141
MaikOvermars 0:4cb1de41d049 142
MaikOvermars 0:4cb1de41d049 143 int main()
MaikOvermars 0:4cb1de41d049 144 {
MaikOvermars 0:4cb1de41d049 145 pc.baud(115200);
MaikOvermars 0:4cb1de41d049 146 motor1_pwm.period_us(60);
MaikOvermars 0:4cb1de41d049 147 motor2_pwm.period_us(60);
MaikOvermars 0:4cb1de41d049 148 current_state = waiting; //we start in state ‘waiting’ and current_state can be accessed by all functions
MaikOvermars 0:4cb1de41d049 149 u1 = 0.0f; //initial output to motors is 0.
MaikOvermars 10:7339dca7d604 150 u2 = 0.0f;
MaikOvermars 10:7339dca7d604 151 loop_ticker.attach(&loop_function, 1/samplingfreq); //Run the function loop_function 1000 times per second
MaikOvermars 0:4cb1de41d049 152
MaikOvermars 0:4cb1de41d049 153 while (true) { } //Do nothing here (timing purposes)
MaikOvermars 0:4cb1de41d049 154 }