Whose Line is it Anyways / Mbed OS PM2_WLiiA_robot_code

robot code for summer school

Dependencies:   PM2_Libary Eigen

Fork of PM2_Example_Summer_School by Alex Hawkins

Robot_Library/robot.cpp@74:76c7a805f63d, 2022-05-30 (annotated)

Committer:
eversonrosed
Date:
Mon May 30 20:19:56 2022 +0200
Branch:
distance-sensor
Revision:
74:76c7a805f63d
Parent:
73:667d568da72a
Child:
76:2302f2b51e63
robot works better

Who changed what in which revision?

UserRevisionLine numberNew contents of line
seas726 49:7da71f479dac 1 #include "robot.h"
seas726 49:7da71f479dac 2 #include "EncoderCounter.h"
seas726 49:7da71f479dac 3 #include "PeripheralNames.h"
seas726 49:7da71f479dac 4 #include "PinNames.h"
eversonrosed 73:667d568da72a 5 #include <array>
seas726 56:3fce0a9bb6df 6 #include <cstdint>
seas726 49:7da71f479dac 7 #include <cstdio>
eversonrosed 73:667d568da72a 8 #include <cmath>
eversonrosed 73:667d568da72a 9
eversonrosed 74:76c7a805f63d 10 static float ComputeAngle(std::uint8_t raw, float default_val);
eversonrosed 74:76c7a805f63d 11 static float Multiplier(float angle);
seas726 49:7da71f479dac 12
eversonrosed 60:85a40e69ced6 13 Robot::Robot()
eversonrosed 60:85a40e69ced6 14 : dist(PB_1), // initialize all of the physical ports
eversonrosed 60:85a40e69ced6 15 bit0(PH_1), bit1(PC_2), bit2(PC_3),
eversonrosed 60:85a40e69ced6 16 ir_sensor_0(dist, bit0, bit1, bit2, 0), // one IR sensor
eversonrosed 60:85a40e69ced6 17 i2c2(PB_9, PB_8), // line sensor
eversonrosed 73:667d568da72a 18 line_sensor(i2c2), enable_motors(PB_15), pwm_M1(PB_13),
eversonrosed 73:667d568da72a 19 pwm_M2(PA_9), // motors + encoders
eversonrosed 72:9325748d2d02 20 encoder_M1(PA_6, PC_7), encoder_M2(PB_6, PB_7) {
eversonrosed 60:85a40e69ced6 21 // initialize all variables
eversonrosed 60:85a40e69ced6 22 wheel_to_robot << -WHEEL_RADIUS / 2.0f, WHEEL_RADIUS / 2.0f,
eversonrosed 60:85a40e69ced6 23 -WHEEL_RADIUS / DISTANCE_BETWEEN_WHEELS,
eversonrosed 60:85a40e69ced6 24 -WHEEL_RADIUS / DISTANCE_BETWEEN_WHEELS; // transformation matrix
eversonrosed 60:85a40e69ced6 25 robot_to_wheel = wheel_to_robot.inverse();
seas726 56:3fce0a9bb6df 26
eversonrosed 60:85a40e69ced6 27 robot_speed_desired.setZero(); // zero out all speeds
eversonrosed 60:85a40e69ced6 28 wheel_speed_desired.setZero();
eversonrosed 60:85a40e69ced6 29 wheel_speed_smooth.setZero();
eversonrosed 60:85a40e69ced6 30 robot_speed_actual.setZero();
eversonrosed 60:85a40e69ced6 31 wheel_speed_actual.setZero();
eversonrosed 60:85a40e69ced6 32
eversonrosed 60:85a40e69ced6 33 // MOTORS + MOTION
seas726 49:7da71f479dac 34
eversonrosed 60:85a40e69ced6 35 // TRAJECTORY PLANNERS
eversonrosed 60:85a40e69ced6 36 trajectoryPlanners[0] = new Motion();
eversonrosed 60:85a40e69ced6 37 trajectoryPlanners[1] = new Motion();
seas726 49:7da71f479dac 38
eversonrosed 60:85a40e69ced6 39 trajectoryPlanners[0]->setProfileVelocity(MAX_MOTOR_VOLTAGE * KN / 60.0f);
eversonrosed 60:85a40e69ced6 40 trajectoryPlanners[1]->setProfileVelocity(MAX_MOTOR_VOLTAGE * KN / 60.0f);
eversonrosed 60:85a40e69ced6 41 trajectoryPlanners[0]->setProfileAcceleration(10.0f);
eversonrosed 60:85a40e69ced6 42 trajectoryPlanners[1]->setProfileAcceleration(10.0f);
eversonrosed 60:85a40e69ced6 43 trajectoryPlanners[0]->setProfileDeceleration(10.0f);
eversonrosed 60:85a40e69ced6 44 trajectoryPlanners[1]->setProfileDeceleration(10.0f);
seas726 49:7da71f479dac 45
eversonrosed 60:85a40e69ced6 46 // SPEED CONTROLLERS
eversonrosed 60:85a40e69ced6 47 speedControllers[0] = new SpeedController(
eversonrosed 60:85a40e69ced6 48 COUNTS_PER_TURN, KN, MAX_MOTOR_VOLTAGE, pwm_M1, encoder_M1);
eversonrosed 60:85a40e69ced6 49 speedControllers[1] = new SpeedController(
eversonrosed 60:85a40e69ced6 50 COUNTS_PER_TURN, KN, MAX_MOTOR_VOLTAGE, pwm_M2, encoder_M2);
seas726 49:7da71f479dac 51
eversonrosed 60:85a40e69ced6 52 speedControllers[0]->setSpeedCntrlGain(
eversonrosed 60:85a40e69ced6 53 0.04f); // adjust speed controller gains
eversonrosed 60:85a40e69ced6 54 speedControllers[1]->setSpeedCntrlGain(0.04f);
eversonrosed 60:85a40e69ced6 55 speedControllers[0]->setMaxAccelerationRPS(
eversonrosed 60:85a40e69ced6 56 999.0f); // adjust max. acceleration for smooth movement
eversonrosed 60:85a40e69ced6 57 speedControllers[1]->setMaxAccelerationRPS(999.0f);
seas726 49:7da71f479dac 58 }
seas726 49:7da71f479dac 59
eversonrosed 60:85a40e69ced6 60 Robot::~Robot() {
eversonrosed 60:85a40e69ced6 61 delete trajectoryPlanners[0];
eversonrosed 60:85a40e69ced6 62 delete trajectoryPlanners[1];
eversonrosed 60:85a40e69ced6 63 delete speedControllers[0];
eversonrosed 60:85a40e69ced6 64 delete speedControllers[1];
eversonrosed 54:b442660523df 65 }
eversonrosed 54:b442660523df 66
seas726 49:7da71f479dac 67 void Robot::Update() {
seas726 49:7da71f479dac 68
eversonrosed 60:85a40e69ced6 69 controller.Update();
eversonrosed 73:667d568da72a 70
eversonrosed 73:667d568da72a 71 wheel_speed_actual << speedControllers[0]->getSpeedRPS(),
eversonrosed 73:667d568da72a 72 speedControllers[1]->getSpeedRPS();
eversonrosed 67:90f378806cbe 73 robot_speed_actual = wheel_to_robot * wheel_speed_actual;
seas726 49:7da71f479dac 74
eversonrosed 60:85a40e69ced6 75 switch (state) {
eversonrosed 73:667d568da72a 76 case INITIAL:
eversonrosed 73:667d568da72a 77 Initial();
eversonrosed 73:667d568da72a 78 break;
eversonrosed 73:667d568da72a 79 case IDLE:
eversonrosed 73:667d568da72a 80 Idle();
eversonrosed 73:667d568da72a 81 break;
eversonrosed 73:667d568da72a 82 case FOLLOWING_LINE:
eversonrosed 73:667d568da72a 83 FollowingLine();
eversonrosed 73:667d568da72a 84 break;
eversonrosed 73:667d568da72a 85 case RIGHT_TURN_90:
eversonrosed 73:667d568da72a 86 RightTurn_90();
eversonrosed 73:667d568da72a 87 break;
eversonrosed 73:667d568da72a 88 case LEFT_TURN_90:
eversonrosed 73:667d568da72a 89 LeftTurn_90();
eversonrosed 73:667d568da72a 90 break;
eversonrosed 73:667d568da72a 91 case AVOIDING_OBSTACLE:
eversonrosed 73:667d568da72a 92 AvoidObstacle();
eversonrosed 73:667d568da72a 93 break;
eversonrosed 73:667d568da72a 94 default:
eversonrosed 73:667d568da72a 95 state = IDLE; // on default, stop the car
eversonrosed 60:85a40e69ced6 96 }
eversonrosed 73:667d568da72a 97
eversonrosed 67:90f378806cbe 98 wheel_speed_desired = robot_to_wheel * robot_speed_desired;
eversonrosed 67:90f378806cbe 99
eversonrosed 67:90f378806cbe 100 // smooth desired wheel_speeds
eversonrosed 73:667d568da72a 101 trajectoryPlanners[0]->incrementToVelocity(
eversonrosed 73:667d568da72a 102 wheel_speed_desired(0) / (2.0f * M_PI), controller.Period());
eversonrosed 73:667d568da72a 103 trajectoryPlanners[1]->incrementToVelocity(
eversonrosed 73:667d568da72a 104 wheel_speed_desired(1) / (2.0f * M_PI), controller.Period());
eversonrosed 73:667d568da72a 105 wheel_speed_smooth << trajectoryPlanners[0]->getVelocity(),
eversonrosed 73:667d568da72a 106 trajectoryPlanners[1]->getVelocity();
eversonrosed 67:90f378806cbe 107
eversonrosed 67:90f378806cbe 108 // command speedController objects
eversonrosed 67:90f378806cbe 109 speedControllers[0]->setDesiredSpeedRPS(wheel_speed_smooth(0));
eversonrosed 67:90f378806cbe 110 speedControllers[1]->setDesiredSpeedRPS(wheel_speed_smooth(1));
seas726 49:7da71f479dac 111 }
seas726 49:7da71f479dac 112
eversonrosed 60:85a40e69ced6 113 void Robot::Initial() {
eversonrosed 60:85a40e69ced6 114 // initialize the robot.
eversonrosed 72:9325748d2d02 115 enable_motors = 0;
eversonrosed 60:85a40e69ced6 116 // motors_enabled = false;
eversonrosed 60:85a40e69ced6 117 robot_speed_desired(0) = 0.0f; // set speed and rotational velocity to zero
eversonrosed 60:85a40e69ced6 118 robot_speed_desired(1) = 0.0f;
seas726 49:7da71f479dac 119
eversonrosed 60:85a40e69ced6 120 if (controller.GetTurnedOn()) // check to see if blue button is toggled
eversonrosed 60:85a40e69ced6 121 {
eversonrosed 72:9325748d2d02 122 enable_motors = 1;
eversonrosed 60:85a40e69ced6 123 state = FOLLOWING_LINE;
eversonrosed 60:85a40e69ced6 124 }
seas726 49:7da71f479dac 125 }
seas726 49:7da71f479dac 126
eversonrosed 60:85a40e69ced6 127 void Robot::Idle() {
eversonrosed 72:9325748d2d02 128 enable_motors = 0;
eversonrosed 60:85a40e69ced6 129 robot_speed_desired(0) = 0.0f; // set speed and rotational velocity to zero
eversonrosed 60:85a40e69ced6 130 robot_speed_desired(1) = 0.0f;
eversonrosed 73:667d568da72a 131 if (controller.GetTurnedOn()) {
eversonrosed 72:9325748d2d02 132 enable_motors = 1;
eversonrosed 72:9325748d2d02 133 state = FOLLOWING_LINE;
eversonrosed 72:9325748d2d02 134 }
seas726 49:7da71f479dac 135 }
seas726 49:7da71f479dac 136
seas726 56:3fce0a9bb6df 137 void Robot::FollowingLine() // Updates once per cycle.
seas726 49:7da71f479dac 138 {
eversonrosed 60:85a40e69ced6 139 if (!controller.GetTurnedOn()) {
eversonrosed 60:85a40e69ced6 140 state = IDLE;
eversonrosed 60:85a40e69ced6 141 return;
eversonrosed 60:85a40e69ced6 142 }
seas726 56:3fce0a9bb6df 143
eversonrosed 73:667d568da72a 144 uint8_t raw = line_sensor.getRaw();
eversonrosed 74:76c7a805f63d 145 float angle = ComputeAngle(raw, previous_error_value);
eversonrosed 60:85a40e69ced6 146
eversonrosed 60:85a40e69ced6 147 // if(IsSharpTurn(binary_sensor_data)) { return; } // check if the sensor
eversonrosed 60:85a40e69ced6 148 // reads in any sharp turns. if so, exit the PID movement and turn sharply.
eversonrosed 60:85a40e69ced6 149 // first test PID movement. it is possible that PID movement works just as
eversonrosed 60:85a40e69ced6 150 // well.
eversonrosed 60:85a40e69ced6 151
eversonrosed 73:667d568da72a 152 PID_Move(angle); // move the robot smoothly with error
eversonrosed 73:667d568da72a 153 // calculation and stuff?
seas726 56:3fce0a9bb6df 154 }
seas726 56:3fce0a9bb6df 155
eversonrosed 60:85a40e69ced6 156 void Robot::RightTurn_90() {
eversonrosed 60:85a40e69ced6 157 // count encoder values and turn until the motor has rotated ~ 90 degrees
eversonrosed 60:85a40e69ced6 158 // im actually not sure if we need this, try testing with just the PID system
eversonrosed 60:85a40e69ced6 159 // first
seas726 56:3fce0a9bb6df 160 }
seas726 56:3fce0a9bb6df 161
eversonrosed 60:85a40e69ced6 162 void Robot::LeftTurn_90() {
eversonrosed 60:85a40e69ced6 163 // count encoder values and turn until the motor has rotated ~ 90 degrees
eversonrosed 60:85a40e69ced6 164 // im actually not sure if we need this, try testing with just the PID system
eversonrosed 60:85a40e69ced6 165 // first
seas726 56:3fce0a9bb6df 166 }
seas726 56:3fce0a9bb6df 167
eversonrosed 73:667d568da72a 168 void Robot::AvoidObstacle() {
eversonrosed 70:0e9e3c6223d1 169 // TODO
eversonrosed 70:0e9e3c6223d1 170 }
eversonrosed 70:0e9e3c6223d1 171
eversonrosed 73:667d568da72a 172 void Robot::PID_Move(float errval) // for following smooth lines ONLY
seas726 56:3fce0a9bb6df 173 {
eversonrosed 60:85a40e69ced6 174 float dt = controller.Period();
eversonrosed 60:85a40e69ced6 175
eversonrosed 60:85a40e69ced6 176 integral_error += dt * errval;
seas726 49:7da71f479dac 177
eversonrosed 73:667d568da72a 178 float integral_term = k_int * integral_error;
eversonrosed 74:76c7a805f63d 179 float derivative_term = k_deriv * robot_speed_actual(1);
seas726 49:7da71f479dac 180
eversonrosed 73:667d568da72a 181 float control_input = k_prop * errval + integral_term + derivative_term;
eversonrosed 74:76c7a805f63d 182 float multiplier = sqrt(Multiplier(errval));
eversonrosed 60:85a40e69ced6 183
eversonrosed 74:76c7a805f63d 184 robot_speed_desired(0) = multiplier * TRANSLATIONAL_VELOCITY;
eversonrosed 74:76c7a805f63d 185 robot_speed_desired(1) = control_input / multiplier;
eversonrosed 60:85a40e69ced6 186 previous_error_value = errval;
eversonrosed 60:85a40e69ced6 187
eversonrosed 60:85a40e69ced6 188 // Delay total_error/2. not exactly sure why.
seas726 56:3fce0a9bb6df 189 }
seas726 56:3fce0a9bb6df 190
eversonrosed 60:85a40e69ced6 191 bool Robot::IsSharpTurn(int binary_sensor_data) {
eversonrosed 60:85a40e69ced6 192 return binary_sensor_data & 0b11110000 || binary_sensor_data & 0b00001111;
seas726 56:3fce0a9bb6df 193 }
seas726 56:3fce0a9bb6df 194
eversonrosed 60:85a40e69ced6 195 void Robot::PID_Delay(int ms) {
eversonrosed 60:85a40e69ced6 196 // add in delay ?
eversonrosed 60:85a40e69ced6 197 // implement
seas726 56:3fce0a9bb6df 198 }
eversonrosed 73:667d568da72a 199
eversonrosed 74:76c7a805f63d 200 static float ComputeAngle(std::uint8_t raw, float default_val) {
eversonrosed 73:667d568da72a 201 const int line_sensor_count = 8;
eversonrosed 73:667d568da72a 202 uint8_t line_sensor_bits_count;
eversonrosed 73:667d568da72a 203 std::array<float, line_sensor_count> line_sensor_weight{
eversonrosed 73:667d568da72a 204 3.5, 2.5, 1.5, 0.5, -0.5, -1.5, -2.5, -3.5}; // [m]
eversonrosed 73:667d568da72a 205 std::array<float, line_sensor_count> line_sensor_value{};
eversonrosed 73:667d568da72a 206 float line_sensor_position; // [m]
eversonrosed 73:667d568da72a 207 const float line_sensor_distance = 12.5e-3; // [m]
eversonrosed 73:667d568da72a 208
eversonrosed 73:667d568da72a 209 // fill bits into the sensor array
eversonrosed 73:667d568da72a 210 // also count the sensors detecting a black line
eversonrosed 73:667d568da72a 211 line_sensor_bits_count = 0;
eversonrosed 73:667d568da72a 212 for (int i = 0; i < line_sensor_count; i++) {
eversonrosed 73:667d568da72a 213 line_sensor_value[i] = (raw >> i) & 0x01;
eversonrosed 73:667d568da72a 214 line_sensor_bits_count += line_sensor_value[i];
eversonrosed 73:667d568da72a 215 }
eversonrosed 73:667d568da72a 216
eversonrosed 73:667d568da72a 217 // getting the line position as a weighted mean
eversonrosed 74:76c7a805f63d 218 if (line_sensor_bits_count == 8) {
eversonrosed 74:76c7a805f63d 219 return default_val;
eversonrosed 74:76c7a805f63d 220 } else if (line_sensor_bits_count > 0) {
eversonrosed 74:76c7a805f63d 221 for (int i = 0; i < line_sensor_count; i++) {
eversonrosed 73:667d568da72a 222 line_sensor_position += line_sensor_value[i] * line_sensor_weight[i] /
eversonrosed 73:667d568da72a 223 float(line_sensor_bits_count);
eversonrosed 73:667d568da72a 224 }
eversonrosed 74:76c7a805f63d 225 } else {
eversonrosed 74:76c7a805f63d 226 line_sensor_position = 0.0;
eversonrosed 73:667d568da72a 227 }
eversonrosed 73:667d568da72a 228 line_sensor_position *= line_sensor_distance;
eversonrosed 73:667d568da72a 229
eversonrosed 73:667d568da72a 230 float line_sensor_angle; // [rad]
eversonrosed 73:667d568da72a 231 const float line_sensor_center_distance = 40e-3; // [m] Set this parameter yourself
eversonrosed 73:667d568da72a 232
eversonrosed 73:667d568da72a 233 // getting an angle out of the position
eversonrosed 73:667d568da72a 234 line_sensor_angle = atan2(line_sensor_position, line_sensor_center_distance);
eversonrosed 73:667d568da72a 235 return line_sensor_angle;
eversonrosed 73:667d568da72a 236 }
eversonrosed 74:76c7a805f63d 237
eversonrosed 74:76c7a805f63d 238 static float Multiplier(float angle)
eversonrosed 74:76c7a805f63d 239 {
eversonrosed 74:76c7a805f63d 240 return 1 / (1 + 2 * angle * angle);
eversonrosed 74:76c7a805f63d 241 }