Biorobotics / Robot-Software

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Dependencies:   HIDScope MODSERIAL QEI biquadFilter mbed Servo

main.cpp@25:734a26538711, 2018-10-29 (annotated)

Committer:
MaikOvermars
Date:
Mon Oct 29 14:45:01 2018 +0000
Revision:
25:734a26538711
Parent:
23:7d83af123c43
Child:
28:d952367fc0fc
fixed processing chain to include individual filters for the emg signals

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 17:1f93c83e211f 8 #include "processing_chain_emg.h"
MaikOvermars 0:4cb1de41d049 9
MaikOvermars 0:4cb1de41d049 10 //Define objects
MaikOvermars 0:4cb1de41d049 11 MODSERIAL pc(USBTX, USBRX);
MaikOvermars 0:4cb1de41d049 12 HIDScope scope(2);
MaikOvermars 0:4cb1de41d049 13
MaikOvermars 10:7339dca7d604 14 // emg inputs
MaikOvermars 0:4cb1de41d049 15 AnalogIn emg0( A0 );
MaikOvermars 0:4cb1de41d049 16 AnalogIn emg1( A1 );
MaikOvermars 0:4cb1de41d049 17
MaikOvermars 10:7339dca7d604 18 // motor ouptuts
MaikOvermars 0:4cb1de41d049 19 PwmOut motor1_pwm(D5);
MaikOvermars 0:4cb1de41d049 20 DigitalOut motor1_dir(D4);
MaikOvermars 0:4cb1de41d049 21 PwmOut motor2_pwm(D7);
MaikOvermars 0:4cb1de41d049 22 DigitalOut motor2_dir(D6);
MaikOvermars 0:4cb1de41d049 23
SvenD97 14:4744cc6c90f4 24 // defining encoders
MaikOvermars 16:0280a604cf7e 25 QEI motor_1_encoder(D12,D13,NC,32);
MaikOvermars 16:0280a604cf7e 26 QEI motor_2_encoder(D10,D11,NC,32);
SvenD97 14:4744cc6c90f4 27
MaikOvermars 17:1f93c83e211f 28 // other objects
MaikOvermars 0:4cb1de41d049 29 AnalogIn potmeter1(A2);
MaikOvermars 0:4cb1de41d049 30 AnalogIn potmeter2(A3);
MaikOvermars 0:4cb1de41d049 31 DigitalIn button(D0);
MaikOvermars 0:4cb1de41d049 32
SvenD97 14:4744cc6c90f4 33 // tickers and timers
MaikOvermars 16:0280a604cf7e 34 Ticker loop_ticker;
MaikOvermars 0:4cb1de41d049 35 Timer state_timer;
MaikOvermars 0:4cb1de41d049 36
MaikOvermars 0:4cb1de41d049 37 enum States {failure, waiting, calib_enc, calib_emg, operational, demo}; //All possible robot states
MaikOvermars 0:4cb1de41d049 38
MaikOvermars 0:4cb1de41d049 39 //Global variables/objects
MaikOvermars 0:4cb1de41d049 40 States current_state;
MaikOvermars 16:0280a604cf7e 41
MaikOvermars 17:1f93c83e211f 42 double des_vx, des_vy, x, y, q1, q2, qref1, qref2, e1, e2, u1, u2, raw_emg_0, process_emg_0, raw_emg_1, process_emg_1; //will be set by the motor_controller function
MaikOvermars 17:1f93c83e211f 43 double vxmax = 1.0, vymax = 1.0;
bjonkheer 23:7d83af123c43 44
MaikOvermars 0:4cb1de41d049 45 int counts_per_rotation = 32;
MaikOvermars 0:4cb1de41d049 46 bool state_changed = false;
SvenD97 8:bba05e863b68 47 const double T = 0.001;
bjonkheer 23:7d83af123c43 48
MaikOvermars 0:4cb1de41d049 49
MaikOvermars 17:1f93c83e211f 50 // Functions
MaikOvermars 0:4cb1de41d049 51 void measure_all()
MaikOvermars 0:4cb1de41d049 52 {
bjonkheer 23:7d83af123c43 53
MaikOvermars 16:0280a604cf7e 54 q1 = motor_1_encoder.getPulses()*2.0f*3.1415926535f/counts_per_rotation; //do this here, and not in the encoder interrupt, to reduce computational load
MaikOvermars 16:0280a604cf7e 55 q2 = motor_2_encoder.getPulses()*2.0f*3.1415926535f/counts_per_rotation;
SvenD97 14:4744cc6c90f4 56 forwardkinematics_function(q1,q2,x,y); //motor_angle is global, this function ne
MaikOvermars 17:1f93c83e211f 57 raw_emg_0 = emg0.read(); //sample analog voltages (all sampling theory applies, you might get aliasing etc.)
MaikOvermars 17:1f93c83e211f 58 raw_emg_1 = emg1.read();
MaikOvermars 17:1f93c83e211f 59 processing_chain_emg(raw_emg_0, raw_emg_1, process_emg_0, process_emg_1); // processes the emg signals
MaikOvermars 0:4cb1de41d049 60 }
MaikOvermars 0:4cb1de41d049 61
MaikOvermars 0:4cb1de41d049 62 void output_all() {
MaikOvermars 0:4cb1de41d049 63 motor1_pwm = fabs(u1);
MaikOvermars 16:0280a604cf7e 64 motor1_dir = u1 > 0.0f;
MaikOvermars 0:4cb1de41d049 65 motor2_pwm = fabs(u2);
MaikOvermars 16:0280a604cf7e 66 motor2_dir = u2 > 0.0f;
MaikOvermars 0:4cb1de41d049 67 static int output_counter = 0;
MaikOvermars 0:4cb1de41d049 68 output_counter++;
MaikOvermars 0:4cb1de41d049 69 if (output_counter == 100) {pc.printf("Something something... %f",u1); output_counter = 0;} //Print to screen at 10 Hz with MODSERIAL
MaikOvermars 0:4cb1de41d049 70 }
MaikOvermars 0:4cb1de41d049 71
MaikOvermars 0:4cb1de41d049 72 void state_machine() {
MaikOvermars 0:4cb1de41d049 73 switch(current_state) { //States can be: failure, wait, calib_enc, calib_emg, operational, demo,
MaikOvermars 0:4cb1de41d049 74 case waiting: //Nothing useful here, maybe a blinking LED for fun and communication to the user
MaikOvermars 0:4cb1de41d049 75 if (button.read()==true)
MaikOvermars 0:4cb1de41d049 76 {
MaikOvermars 0:4cb1de41d049 77 current_state = calib_enc; //the NEXT loop we will be in calib_enc state
SvenD97 9:8e1112874c12 78 // no state_changed action?
MaikOvermars 0:4cb1de41d049 79 }
MaikOvermars 0:4cb1de41d049 80 break; //to avoid falling through to the next state, although this can sometimes be very useful.
MaikOvermars 0:4cb1de41d049 81
MaikOvermars 0:4cb1de41d049 82 case calib_enc:
MaikOvermars 0:4cb1de41d049 83 if (state_changed==true)
MaikOvermars 0:4cb1de41d049 84 {
MaikOvermars 0:4cb1de41d049 85 state_timer.reset();
MaikOvermars 0:4cb1de41d049 86 state_timer.start();
MaikOvermars 0:4cb1de41d049 87 state_changed = false;
MaikOvermars 0:4cb1de41d049 88 }
bjonkheer 18:ea605c49afee 89 u1 = 0.55f; //a low PWM value to move the motors slowly (0.0 to 0.45 don’t do much due to friction)
MaikOvermars 0:4cb1de41d049 90 // fabs(motor1.velocity()) < 0.1f &&
MaikOvermars 0:4cb1de41d049 91 if (state_timer.read() > 5.0f) {
MaikOvermars 0:4cb1de41d049 92 current_state = calib_emg; //the NEXT loop we will be in calib_emg state
MaikOvermars 0:4cb1de41d049 93 state_changed = true;
MaikOvermars 0:4cb1de41d049 94 }
MaikOvermars 0:4cb1de41d049 95 break;
MaikOvermars 0:4cb1de41d049 96
MaikOvermars 0:4cb1de41d049 97 case calib_emg: //calibrate emg-signals
MaikOvermars 17:1f93c83e211f 98 current_state = operational;
MaikOvermars 0:4cb1de41d049 99 break;
MaikOvermars 0:4cb1de41d049 100
MaikOvermars 0:4cb1de41d049 101 case operational: //interpreting emg-signals to move the end effector
bjonkheer 23:7d83af123c43 102
MaikOvermars 17:1f93c83e211f 103 // here we have to determine the desired velocity based on the processed emg signals and calibration
MaikOvermars 17:1f93c83e211f 104 if (process_emg_0 >= 0.16) { des_vx = vxmax; }
MaikOvermars 17:1f93c83e211f 105 else if(process_emg_0 >= 0.09) { des_vx = vxmax * 0.66; }
MaikOvermars 17:1f93c83e211f 106 else if(process_emg_0 >= 0.02) { des_vx = vxmax * 0.33; }
MaikOvermars 17:1f93c83e211f 107 else { des_vx = 0; }
MaikOvermars 17:1f93c83e211f 108
MaikOvermars 17:1f93c83e211f 109 if (process_emg_1 >= 0.16) { des_vy = vymax; }
MaikOvermars 17:1f93c83e211f 110 else if(process_emg_1 >= 0.09) { des_vy = vymax * 0.66; }
MaikOvermars 17:1f93c83e211f 111 else if(process_emg_1 >= 0.02) { des_vy = vymax * 0.33; }
MaikOvermars 17:1f93c83e211f 112 else { des_vy = 0; }
MaikOvermars 17:1f93c83e211f 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 demo: //moving according to a specified trajectory
MaikOvermars 0:4cb1de41d049 119
MaikOvermars 17:1f93c83e211f 120 if (button.read() == true) { current_state = operational; }
MaikOvermars 0:4cb1de41d049 121
MaikOvermars 0:4cb1de41d049 122 break;
MaikOvermars 0:4cb1de41d049 123
MaikOvermars 0:4cb1de41d049 124 case failure: //no way to get out
MaikOvermars 0:4cb1de41d049 125 u1 = 0.0f;
MaikOvermars 17:1f93c83e211f 126 u2 = 0.0f;
MaikOvermars 0:4cb1de41d049 127 break;
MaikOvermars 0:4cb1de41d049 128 }
MaikOvermars 0:4cb1de41d049 129 }
MaikOvermars 0:4cb1de41d049 130
MaikOvermars 0:4cb1de41d049 131 void motor_controller()
MaikOvermars 0:4cb1de41d049 132 {
MaikOvermars 0:4cb1de41d049 133 if (current_state >= operational) { // we can (ab)use the fact that an enum is actually an integer, so math/logic rules still apply
MaikOvermars 16:0280a604cf7e 134 inversekinematics_function(x,y,T,qref1,qref2,q1,q2,des_vx,des_vy); //many different states can modify your reference position, so just do the inverse kinematics once, here
MaikOvermars 16:0280a604cf7e 135 e1 = qref1 - q1; //tracking error (q_ref - q_meas)
MaikOvermars 16:0280a604cf7e 136 e2 = qref2 - q2;
MaikOvermars 17:1f93c83e211f 137 PID_controller(e1,e2,u1,u2,T); //feedback controller or with possibly fancy controller additions...; pass by reference
MaikOvermars 0:4cb1de41d049 138 } //otherwise we just don’t mess with the value of control variable ‘u’ that is set somewhere in the state-machine.
MaikOvermars 0:4cb1de41d049 139 }
MaikOvermars 0:4cb1de41d049 140
MaikOvermars 0:4cb1de41d049 141
MaikOvermars 0:4cb1de41d049 142 void loop_function() {
MaikOvermars 0:4cb1de41d049 143 measure_all(); //measure all signals
MaikOvermars 0:4cb1de41d049 144 state_machine(); //Do relevant state dependent things
MaikOvermars 0:4cb1de41d049 145 motor_controller(); //Do not put different motor controllers in the states, because every state can re-use the same motor-controller!
MaikOvermars 0:4cb1de41d049 146 output_all(); //Output relevant signals, messages, screen outputs, LEDs etc.
MaikOvermars 0:4cb1de41d049 147 }
MaikOvermars 0:4cb1de41d049 148
MaikOvermars 0:4cb1de41d049 149
MaikOvermars 0:4cb1de41d049 150 int main()
MaikOvermars 0:4cb1de41d049 151 {
MaikOvermars 0:4cb1de41d049 152 pc.baud(115200);
MaikOvermars 0:4cb1de41d049 153 motor1_pwm.period_us(60);
MaikOvermars 0:4cb1de41d049 154 motor2_pwm.period_us(60);
MaikOvermars 0:4cb1de41d049 155 current_state = waiting; //we start in state ‘waiting’ and current_state can be accessed by all functions
MaikOvermars 0:4cb1de41d049 156 u1 = 0.0f; //initial output to motors is 0.
MaikOvermars 10:7339dca7d604 157 u2 = 0.0f;
MaikOvermars 25:734a26538711 158 bqc0.add(&bq0high).add(&bq0notch); // filter cascade for emg
MaikOvermars 25:734a26538711 159 bqc1.add(&bq1high).add(&bq1notch); // filter cascade for emg
MaikOvermars 17:1f93c83e211f 160 loop_ticker.attach(&loop_function, T); //Run the function loop_function 1000 times per second
MaikOvermars 0:4cb1de41d049 161
MaikOvermars 0:4cb1de41d049 162 while (true) { } //Do nothing here (timing purposes)
MaikOvermars 0:4cb1de41d049 163 }