M9 Biorobotics Group 8
De hele robot in 1 keer bam
Dependencies: mbed QEI Servo HIDScope biquadFilter MODSERIAL FastPWM
Diff: main.cpp
- Revision:
- 38:8b597ab8344f
- Parent:
- 37:806c7c8381a7
- Child:
- 39:f9042483b921
--- a/main.cpp Wed Oct 30 14:13:27 2019 +0000
+++ b/main.cpp Wed Oct 30 15:49:09 2019 +0000
@@ -1,14 +1,18 @@
/*
------------------------------ ADD LIBRARIES ------------------------------
*/
-#include "mbed.h" //Base library
-#include "MODSERIAL.h"// in order for connection with the pc
+#include "mbed.h" // Base library
+#include "HIDScope.h" // Scope connection to PC
+#include "MODSERIAL.h" // Serial connection to PC
+#include "BiQuad.h" // Biquad filter management
+#include <vector> // Array management
/*
------------------------------ DEFINE MBED CONNECTIONS ------------------------------
*/
-// PC serial connection
+// PC connections
+HIDScope scope( 4 );
MODSERIAL pc(USBTX, USBRX);
// Buttons
@@ -17,36 +21,102 @@
InterruptIn switch2(SW2);
InterruptIn switch3(SW3);
+// LEDs
+DigitalOut led_g(LED_GREEN);
+DigitalOut led_r(LED_RED);
+DigitalOut led_b(LED_BLUE);
+
+// Analog EMG inputs
+AnalogIn emg1_in (A1); // Right biceps -> x axis
+AnalogIn emg2_in (A2); // Left biceps -> y axis
+AnalogIn emg3_in (A3); // Third muscle -> TBD
+
/*
------------------------------- GLOBAL VARIABLES ------------------------------
+------------------------------ INITIALIZE TICKERS, TIMERS & TIMEOUTS ------------------------------
+*/
+Ticker tickGlobal; // Set global ticker
+Timer timerCalibration; // Set EMG Calibration timer
+
+/*
+------------------------------ INITIALIZE GLOBAL VARIABLES ------------------------------
*/
// State machine variables
-enum GLOBAL_States { global_failure, global_wait, global_cal_emg, global_cal_motor, global_operation, global_demo }; // Define global states
+enum GLOBAL_States { global_failure, global_wait, global_emg_cal, global_motor_cal, global_operation, global_demo }; // Define global states
GLOBAL_States global_curr_state = global_wait; // Initialize global state to waiting state
bool global_state_changed = true; // Enable entry functions
bool failure_mode = false;
-bool cal_emg_done = false;
-bool cal_motor_done = false;
+bool emg_cal_done = false;
+bool motor_cal_done = false;
+
+// EMG Substate variables
+enum EMG_States { emg_wait, emg_cal_MVC, emg_cal_rest, emg_operation }; // Define EMG substates
+EMG_States emg_curr_state = emg_wait; // Initialize EMG substate variable
+bool emg_state_changed = true;
+
+bool emg_sampleNow = false;
+bool emg_calibrateNow = false;
+bool emg_MVC_cal_done = false;
+bool emg_rest_cal_done = false;
// Button press interrupts (to prevent bounce)
bool button1_pressed = false;
bool button2_pressed = false;
bool switch2_pressed = false;
-// Global program variables
-double Fs = 500.0;
-double Ts = 1/Fs;
-
-double Tcal_test = 5.0;
+// Global constants
+const double Fs = 500.0;
+const double Ts = 1/Fs;
/*
------------------------------ HELPER FUNCTIONS ------------------------------
*/
-void doStuff() {} // Empty placeholder function, needs to be deleted at end of project
+// Empty placeholder function, needs to be deleted at end of project
+void doStuff() {}
+
+// Return max value of vector
+double getMax(const vector<double> &vect)
+{
+ double curr_max = 0.0;
+ int vect_n = vect.size();
+ for (int i = 0; i < vect_n; i++) {
+ if (vect[i] > curr_max) {
+ curr_max = vect[i];
+ };
+ }
+ return curr_max;
+}
+// Return mean of vector
+double getMean(const vector<double> &vect)
+{
+ double sum = 0.0;
+ int vect_n = vect.size();
+ for ( int i = 0; i < vect_n; i++ ) {
+ sum += vect[i];
+ }
+ return sum/vect_n;
+}
+// Return standard deviation of vector
+double getStdev(const vector<double> &vect, const double vect_mean)
+{
+ double sum2 = 0.0;
+ int vect_n = vect.size();
+ for ( int i = 0; i < vect_n; i++ ) {
+ sum2 += pow( vect[i] - vect_mean, 2 );
+ }
+ double output = sqrt( sum2 / vect_n );
+ return output;
+}
+
+// Rescale double values to certain range
+double rescale(double input, double out_min, double out_max, double in_min, double in_max)
+{
+ double output = out_min + ((input-in_min)/(in_max-in_min))*(out_max-out_min); // Based on MATLAB rescale function
+ return output;
+}
/*
------------------------------ BUTTON FUNCTIONS ------------------------------
@@ -76,11 +146,301 @@
}
/*
------------------------------- TICKER, TIMER & TIMEOUT FUNCTIONS ------------------------------
+------------------------------ EMG GLOBAL VARIABLES & CONSTANTS ------------------------------
+*/
+
+// Set global constant values for EMG reading & analysis
+const double Tcal = 10.0f; // Calibration duration (s)
+
+// Initialize variables for EMG reading & analysis
+double emg1;
+double emg1_env;
+double emg1_MVC;
+double emg1_rest;
+double emg1_factor;//delete
+double emg1_th;
+double emg1_out;
+double emg1_norm; //delete
+vector<double> emg1_cal;
+int emg1_cal_size; //delete
+int emg1_dir = 1;
+double emg1_out_prev;
+double emg1_dt; //delete
+double emg1_dt_prev;
+double emg1_dtdt; //delete
+
+double emg2;
+double emg2_env;
+double emg2_MVC;
+double emg2_rest;
+double emg2_factor;//delete
+double emg2_th;
+double emg2_out;
+double emg2_norm;//delete
+vector<double> emg2_cal;
+int emg2_cal_size;//delete
+int emg2_dir = 1;
+
+double emg3;
+double emg3_env;
+double emg3_MVC;
+double emg3_rest;
+double emg3_factor;//delete
+double emg3_th;
+double emg3_out;
+double emg3_norm;//delete
+vector<double> emg3_cal;
+int emg3_cal_size;//delete
+int emg3_dir = 1;
+
+/*
+------------------------------ EMG FILTERS ------------------------------
+*/
+
+// Notch biquad filter coefficients (iirnotch Q factor 35 @50Hz) from MATLAB:
+BiQuad bq1_notch( 0.995636295063941, -1.89829218816065, 0.995636295063941, 1, -1.89829218816065, 0.991272590127882); // b01 b11 b21 a01 a11 a21
+BiQuad bq2_notch = bq1_notch;
+BiQuad bq3_notch = bq1_notch;
+BiQuadChain bqc1_notch;
+BiQuadChain bqc2_notch;
+BiQuadChain bqc3_notch;
+
+// Highpass biquad filter coefficients (butter 4th order @10Hz cutoff) from MATLAB
+BiQuad bq1_H1(0.922946103200875, -1.84589220640175, 0.922946103200875, 1, -1.88920703055163, 0.892769008131025); // b01 b11 b21 a01 a11 a21
+BiQuad bq1_H2(1, -2, 1, 1, -1.95046575793011, 0.954143234875078); // b02 b12 b22 a02 a12 a22
+BiQuad bq2_H1 = bq1_H1;
+BiQuad bq2_H2 = bq1_H2;
+BiQuad bq3_H1 = bq1_H1;
+BiQuad bq3_H2 = bq1_H2;
+BiQuadChain bqc1_high;
+BiQuadChain bqc2_high;
+BiQuadChain bqc3_high;
+
+// Lowpass biquad filter coefficients (butter 4th order @5Hz cutoff) from MATLAB:
+BiQuad bq1_L1(5.32116245737504e-08, 1.06423249147501e-07, 5.32116245737504e-08, 1, -1.94396715039462, 0.944882378004138); // b01 b11 b21 a01 a11 a21
+BiQuad bq1_L2(1, 2, 1, 1, -1.97586467534468, 0.976794920438162); // b02 b12 b22 a02 a12 a22
+BiQuad bq2_L1 = bq1_L1;
+BiQuad bq2_L2 = bq1_L2;
+BiQuad bq3_L1 = bq1_L1;
+BiQuad bq3_L2 = bq1_L2;
+BiQuadChain bqc1_low;
+BiQuadChain bqc2_low;
+BiQuadChain bqc3_low;
+
+// Function to check filter stability
+bool checkBQChainStable()
+{
+ bool n_stable = bqc1_notch.stable(); // Check stability of all BQ Chains
+ bool hp_stable = bqc1_high.stable();
+ bool l_stable = bqc1_low.stable();
+
+ if (n_stable && hp_stable && l_stable) {
+ return true;
+ } else {
+ return false;
+ }
+}
+/*
+------------------------------ EMG SUBSTATE FUNCTIONS ------------------------------
*/
-// Initialize tickers and timeouts
-Ticker tickGlobal; // Set global ticker
-Timer timerStateMachineTest; // Set testing timer
+
+// EMG Waiting state
+void do_emg_wait()
+{
+ // Entry function
+ if ( emg_state_changed == true ) {
+ emg_state_changed = false; // Disable entry functions
+
+ button1.fall( &button1Press ); // Change to state MVC calibration on button1 press
+ button2.fall( &button2Press ); // Change to state rest calibration on button2 press
+ }
+
+ // Do nothing until end condition is met
+
+ // State transition guard
+ if ( button1_pressed ) { // MVC calibration
+ button1_pressed = false; // Disable button pressed function until next button press
+ button1.fall( NULL ); // Disable interrupt during calibration
+ button2.fall( NULL ); // Disable interrupt during calibration
+ emg_curr_state = emg_cal_MVC; // Set next state
+ emg_state_changed = true; // Enable entry functions
+
+ } else if ( button2_pressed ) { // Rest calibration
+ button2_pressed = false; // Disable button pressed function until next button press
+ button1.fall( NULL ); // Disable interrupt during calibration
+ button2.fall( NULL ); // Disable interrupt during calibration
+ emg_curr_state = emg_cal_rest; // Set next state
+ emg_state_changed = true; // Enable entry functions
+
+ } else if ( emg_MVC_cal_done && emg_rest_cal_done ) { // Operation mode
+ button1.fall( NULL ); // Disable interrupt during operation
+ button2.fall( NULL ); // Disable interrupt during operation
+ emg_curr_state = emg_operation; // Set next state
+ emg_state_changed = true; // Enable entry functions
+ }
+}
+
+// EMG Calibration state
+void do_emg_cal()
+{
+ // Entry functions
+ if ( emg_state_changed == true ) {
+ emg_state_changed = false; // Disable entry functions
+ led_b = 0; // Turn on calibration led
+
+ timerCalibration.reset();
+ timerCalibration.start(); // Sets up timer to stop calibration after Tcal seconds
+ emg_sampleNow = true; // Enable signal sampling in sampleSignals()
+ emg_calibrateNow = true; // Enable calibration vector functionality in sampleSignals()
+
+ emg1_cal.reserve(Fs * Tcal); // Initialize vector lengths to prevent memory overflow
+ emg2_cal.reserve(Fs * Tcal); // Idem
+ emg3_cal.reserve(Fs * Tcal); // Idem
+ }
+
+ // Do stuff until end condition is met
+ // Set HIDScope outputs
+ scope.set(0, emg1 );
+ scope.set(1, emg1_env );
+ //scope.set(2, emg2_env );
+ //scope.set(3, emg3_env );
+ scope.send();
+
+ // State transition guard
+ if ( timerCalibration.read() >= Tcal ) { // After interval Tcal the calibration step is finished
+ emg_sampleNow = false; // Disable signal sampling in sampleSignals()
+ emg_calibrateNow = false; // Disable calibration sampling
+ led_b = 1; // Turn off calibration led
+
+ // Extract EMG scale data from calibration
+ switch( emg_curr_state ) {
+ case emg_cal_MVC:
+ emg1_MVC = getMax(emg1_cal); // Store max value of MVC globally
+ emg2_MVC = getMax(emg2_cal);
+ emg3_MVC = getMax(emg3_cal);
+
+ emg_MVC_cal_done = true; // Set up transition to EMG operation mode
+ break;
+ case emg_cal_rest:
+ emg1_rest = getMean(emg1_cal); // Store mean of EMG in rest globally
+ emg2_rest = getMean(emg2_cal);
+ emg3_rest = getMean(emg3_cal);
+ emg_rest_cal_done = true; // Set up transition to EMG operation mode
+ break;
+ }
+ vector<double>().swap(emg1_cal); // Empty vector to prevent memory overflow
+ vector<double>().swap(emg2_cal);
+ vector<double>().swap(emg3_cal);
+
+ emg_curr_state = emg_wait; // Set next substate
+ emg_state_changed = true; // Enable substate entry function
+ }
+}
+
+// EMG Operation state
+void do_emg_operation()
+{
+ // Entry function
+ if ( emg_state_changed == true ) {
+ emg_state_changed = false; // Disable entry functions
+ double margin_percentage = 5; // Set up % margin for rest
+
+ emg1_factor = 1 / emg1_MVC; // Factor to normalize MVC
+ emg1_th = emg1_rest * emg1_factor + margin_percentage/100; // Set normalized rest threshold
+ emg2_factor = 1 / emg2_MVC; // Factor to normalize MVC
+ emg2_th = emg2_rest * emg2_factor + margin_percentage/100; // Set normalized rest threshold
+ emg3_factor = 1 / emg3_MVC; // Factor to normalize MVC
+ emg3_th = emg3_rest * emg3_factor + margin_percentage/100; // Set normalized rest threshold
+
+
+ // ------- TO DO: MAKE SURE THESE BUTTONS DO NOT BOUNCE (e.g. with button1.rise() ) ------
+ //button1.fall( &toggleEMG1Dir ); // Change to state MVC calibration on button1 press
+ //button2.fall( &toggleEMG2Dir ); // Change to state rest calibration on button2 press
+
+ emg_sampleNow = true; // Enable signal sampling in sampleSignals()
+ emg_calibrateNow = false; // Disable calibration vector functionality in sampleSignals()
+ }
+
+ // Do stuff until end condition is met
+ emg1_norm = emg1_env * emg1_factor; // Normalize EMG signal with calibrated factor
+ emg2_norm = emg2_env * emg2_factor; // Idem
+ emg3_norm = emg3_env * emg3_factor; // Idem
+
+ emg1_out_prev = emg1_out; // Set previous emg_out signal
+ emg1_dt_prev = emg1_dt; // Set previous emg_out_dt signal
+
+ // Set normalized EMG output signal (CAN BE MOVED TO EXTERNAL FUNCTION BECAUSE IT IS REPEATED 3 TIMES)
+ if ( emg1_norm < emg1_th ) { // If below threshold, emg_out = 0 (ignored)
+ emg1_out = 0.0;
+ } else if ( emg1_norm > 1.0f ) { // If above MVC (e.g. due to filtering), emg_out = 1 (max value)
+ emg1_out = 1.0;
+ } else { // If in between threshold and MVC, scale EMG signal accordingly
+ // Inputs may be in range [emg_th, 1]
+ // Outputs are scaled to range [0, 1]
+ emg1_out = rescale(emg1_norm, 0, 1, emg1_th, 1);
+ }
+ emg1_dt = (emg1_out - emg1_out_prev) / Ts; // Calculate derivative of filtered normalized output signal
+ emg1_dtdt = (emg1_dt - emg1_dt_prev) / Ts; // Calculate acceleration of filtered normalized output signal
+ emg1_out = emg1_out * emg1_dir; // Set direction of EMG output
+
+ // Idem for emg2
+ if ( emg2_norm < emg2_th ) {
+ emg2_out = 0.0;
+ } else if ( emg2_norm > 1.0f ) {
+ emg2_out = 1.0;
+ } else {
+ emg2_out = rescale(emg2_norm, 0, 1, emg2_th, 1);
+ }
+ emg2_out = emg2_out * emg2_dir; // Set direction of EMG output
+
+ // Idem for emg3
+ if ( emg3_norm < emg3_th ) {
+ emg3_out = 0.0;
+ } else if ( emg3_norm > 1.0f ) {
+ emg3_out = 1.0;
+ } else {
+ emg3_out = rescale(emg3_norm, 0, 1, emg3_th, 1);
+ }
+
+ // Set HIDScope outputs
+ scope.set(0, emg1 );
+ scope.set(1, emg1_out );
+ scope.set(2, emg1_dt );
+ scope.set(3, emg1_dtdt );
+ //scope.set(2, emg2_out );
+ //scope.set(3, emg3_out );
+ scope.send();
+
+ led_g = !led_g;
+
+ // State transition guard
+ if ( false ) {
+ emg_curr_state = emg_wait; // Set next state
+ emg_state_changed = true; // Enable entry function
+ }
+}
+
+/*
+------------------------------ EMG SUBSTATE MACHINE ------------------------------
+*/
+
+void emg_state_machine()
+{
+ switch(emg_curr_state) {
+ case emg_wait:
+ do_emg_wait();
+ break;
+ case emg_cal_MVC:
+ do_emg_cal();
+ break;
+ case emg_cal_rest:
+ do_emg_cal();
+ break;
+ case emg_operation:
+ do_emg_operation();
+ break;
+ }
+}
/*
------------------------------ GLOBAL STATE FUNCTIONS ------------------------------
@@ -162,18 +522,18 @@
} else if ( button1_pressed == true ) { // EMG CALIBRATION
button1_pressed = false;
- global_curr_state = global_cal_emg;
+ global_curr_state = global_emg_cal;
global_state_changed = true;
} else if ( button2_pressed == true ) { // MOTOR CALIBRATION
button2_pressed = false;
- global_curr_state = global_cal_motor;
+ global_curr_state = global_motor_cal;
global_state_changed = true;
}
}
// EMG CALIBRATION MODE
-void do_global_cal_emg()
+void do_global_emg_cal()
{
// Entry function
if ( global_state_changed == true ) {
@@ -184,20 +544,20 @@
doStuff();
// State transition guard
- if ( cal_motor_done == true ) { // OPERATION MODE
- cal_emg_done = true;
+ if ( motor_cal_done == true ) { // OPERATION MODE
+ emg_cal_done = true;
global_curr_state = global_operation;
global_state_changed = true;
} else if ( button1_pressed == true ) { // WAIT MODE
button1_pressed = false;
- cal_emg_done = true;
+ emg_cal_done = true;
global_curr_state = global_wait;
global_state_changed = true;
}
}
// MOTOR CALIBRATION MODE
-void do_global_cal_motor()
+void do_global_motor_cal()
{
// Entry function
if ( global_state_changed == true ) {
@@ -208,13 +568,13 @@
doStuff();
// State transition guard
- if ( cal_emg_done == true ) { // OPERATION MODE
- cal_motor_done = true;
+ if ( emg_cal_done == true ) { // OPERATION MODE
+ motor_cal_done = true;
global_curr_state = global_operation;
global_state_changed = true;
} else if ( button2_pressed == true ) { // WAIT MODE
button2_pressed = false;
- cal_motor_done = true;
+ motor_cal_done = true;
global_curr_state = global_wait;
global_state_changed = true;
}
@@ -249,11 +609,12 @@
case global_wait:
do_global_wait();
break;
- case global_cal_emg:
- do_global_cal_emg();
+ case global_emg_cal:
+ do_global_emg_cal();
+ emg_state_machine();
break;
- case global_cal_motor:
- do_global_cal_motor();
+ case global_motor_cal:
+ do_global_motor_cal();
break;
case global_operation:
do_global_operation();
@@ -264,13 +625,50 @@
}
}
+/*
+------------------------------ READ SAMPLES ------------------------------
+*/
+void sampleSignals()
+{
+ if (emg_sampleNow == true) { // This ticker only samples if the sample flag is true, to prevent unnecessary computations
+ // Read EMG inputs
+ emg1 = emg1_in.read();
+ emg2 = emg2_in.read();
+ emg3 = emg3_in.read();
+
+
+ double emg1_n = bqc1_notch.step( emg1 ); // Filter notch
+ double emg1_hp = bqc1_high.step( emg1_n ); // Filter highpass
+ double emg1_rectify = fabs( emg1_hp ); // Rectify
+ emg1_env = bqc1_low.step( emg1_rectify ); // Filter lowpass (completes envelope)
+
+ double emg2_n = bqc2_notch.step( emg2 ); // Filter notch
+ double emg2_hp = bqc2_high.step( emg2_n ); // Filter highpass
+ double emg2_rectify = fabs( emg2_hp ); // Rectify
+ emg2_env = bqc2_low.step( emg2_rectify ); // Filter lowpass (completes envelope)
+
+ double emg3_n = bqc3_notch.step( emg3 ); // Filter notch
+ double emg3_hp = bqc3_high.step( emg3_n ); // Filter highpass
+ double emg3_rectify = fabs( emg3_hp ); // Rectify
+ emg3_env = bqc3_low.step( emg3_rectify ); // Filter lowpass (completes envelope)
+
+ if (emg_calibrateNow == true) { // Only add values to EMG vectors if calibration flag is true
+ emg1_cal.push_back(emg1_env); // Add values to calibration vector
+ // emg1_cal_size = emg1_cal.size(); // Used for debugging
+ emg2_cal.push_back(emg2_env); // Add values to calibration vector
+ // emg2_cal_size = emg1_cal.size(); // Used for debugging
+ emg3_cal.push_back(emg3_env); // Add values to calibration vector
+ // emg3_cal_size = emg1_cal.size(); // Used for debugging
+ }
+ }
+}
/*
------------------------------ GLOBAL PROGRAM LOOP ------------------------------
*/
void tickGlobalFunc()
{
- // sampleSignalsAndInputs();
+ sampleSignals();
global_state_machine();
// controller();
// outputToMotors();
@@ -287,13 +685,32 @@
global_curr_state = global_wait; // Start off in EMG Wait state
tickGlobal.attach( &tickGlobalFunc, Ts ); // Start global ticker
+ // ---------- Attach filters ----------
+ bqc1_notch.add( &bq1_notch );
+ bqc1_high.add( &bq1_H1 ).add( &bq1_H2 );
+ bqc1_low.add( &bq1_L1 ).add( &bq1_L2 );
+
+ bqc2_notch.add( &bq2_notch );
+ bqc2_high.add( &bq2_H1 ).add( &bq2_H2 );
+ bqc2_low.add( &bq2_L1 ).add( &bq2_L2 );
+
+ bqc3_notch.add( &bq3_notch );
+ bqc3_high.add( &bq3_H1 ).add( &bq3_H2 );
+ bqc3_low.add( &bq3_L1 ).add( &bq3_L2 );
+
+ // ---------- Attach buttons ----------
button1.fall( &button1Press );
button2.fall( &button2Press );
switch2.fall( &switch2Press );
switch3.fall( &switch3Press );
+
+ // ---------- Turn OFF LEDs ----------
+ led_b = 1;
+ led_g = 1;
+ led_r = 1;
while(true) {
- pc.printf("Global state: %i \r\n", global_curr_state);
+ pc.printf("Global state: %i EMG substate: %i\r\n", global_curr_state, emg_curr_state);
wait(0.5f);
}
}
\ No newline at end of file