Cooper Liu / Mbed 2 deprecated ICRSEurobot13

Colour sensors calibrated

Dependencies:   mbed-rtos mbed Servo QEI

Fork of ICRSEurobot13 by Thomas Branch

Processes/Motion/motion.cpp@26:b16f1045108f, 2013-04-10 (annotated)

Committer:
madcowswe
Date:
Wed Apr 10 02:01:51 2013 +0000
Revision:
26:b16f1045108f
Parent:
25:50805ef8c499
Child:
27:7cb3a21d9a2e
Child:
31:791739422122
Motion and motor works, but needs tuning

Who changed what in which revision?

UserRevisionLine numberNew contents of line
rsavitski 25:50805ef8c499 1 ////////////////////////////////////////////////////////////////////////////////
rsavitski 25:50805ef8c499 2 // Motion control unit
rsavitski 25:50805ef8c499 3 ////////////////////////////////////////////////////////////////////////////////
rsavitski 25:50805ef8c499 4 // Takes current state of the robot and target waypoint,
rsavitski 25:50805ef8c499 5 // calculates desired forward and angular velocities and requests those from the motor control layer.
rsavitski 25:50805ef8c499 6 ////////////////////////////////////////////////////////////////////////////////
rsavitski 25:50805ef8c499 7
rsavitski 25:50805ef8c499 8 #include "motion.h"
madcowswe 26:b16f1045108f 9 #include "supportfuncs.h"
rsavitski 25:50805ef8c499 10
rsavitski 25:50805ef8c499 11 namespace motion
rsavitski 25:50805ef8c499 12 {
rsavitski 25:50805ef8c499 13
rsavitski 25:50805ef8c499 14 void motionlayer(void const *dummy)
rsavitski 25:50805ef8c499 15 {
rsavitski 25:50805ef8c499 16 //TODO: current_waypoint global in AI layer
rsavitski 25:50805ef8c499 17 //TODO: threshold for deciding that the waypoint has been achieved
rsavitski 25:50805ef8c499 18
rsavitski 25:50805ef8c499 19 // get target waypoint from AI
rsavitski 25:50805ef8c499 20 Waypoint target_waypoint = *AI::current_waypoint;
rsavitski 25:50805ef8c499 21
rsavitski 25:50805ef8c499 22 // get current state from Kalman
rsavitski 25:50805ef8c499 23 State current_state = Kalman::getState();
rsavitski 25:50805ef8c499 24
rsavitski 25:50805ef8c499 25 float delta_x = target_waypoint.x - current_state.x;
rsavitski 25:50805ef8c499 26 float delta_y = target_waypoint.y - current_state.y;
rsavitski 25:50805ef8c499 27
madcowswe 26:b16f1045108f 28 //printf("motion sees deltax: %f deltay %f\r\n", delta_x, delta_y);
rsavitski 25:50805ef8c499 29
madcowswe 26:b16f1045108f 30 float distance_err = hypot(delta_x, delta_y);
madcowswe 26:b16f1045108f 31
madcowswe 26:b16f1045108f 32 float angle_err = constrainAngle(atan2(delta_y, delta_x) - current_state.theta);
rsavitski 25:50805ef8c499 33
rsavitski 25:50805ef8c499 34
rsavitski 25:50805ef8c499 35 // angular velocity controller
madcowswe 26:b16f1045108f 36 const float p_gain_av = 0.3; //TODO: tune
rsavitski 25:50805ef8c499 37
madcowswe 26:b16f1045108f 38 const float max_av = 0.2*PI; // radians per sec //TODO: tune
rsavitski 25:50805ef8c499 39
rsavitski 25:50805ef8c499 40 // angle error [-pi, pi]
rsavitski 25:50805ef8c499 41 float angular_v = p_gain_av * angle_err;
rsavitski 25:50805ef8c499 42
rsavitski 25:50805ef8c499 43 // constrain range
rsavitski 25:50805ef8c499 44 if (angular_v > max_av)
rsavitski 25:50805ef8c499 45 angular_v = max_av;
rsavitski 25:50805ef8c499 46 else if (angular_v < -max_av)
rsavitski 25:50805ef8c499 47 angular_v = -max_av;
rsavitski 25:50805ef8c499 48
rsavitski 25:50805ef8c499 49
rsavitski 25:50805ef8c499 50 // forward velocity controller
madcowswe 26:b16f1045108f 51 const float p_gain_fv = 0.3; //TODO: tune
rsavitski 25:50805ef8c499 52
madcowswe 26:b16f1045108f 53 float max_fv = 0.2; // meters per sec //TODO: tune
rsavitski 25:50805ef8c499 54 const float angle_envelope_exponent = 8.0; //TODO: tune
rsavitski 25:50805ef8c499 55
rsavitski 25:50805ef8c499 56 // control, distance_err in meters
rsavitski 25:50805ef8c499 57 float forward_v = p_gain_fv * distance_err;
rsavitski 25:50805ef8c499 58
rsavitski 25:50805ef8c499 59 // control the forward velocity envelope based on angular error
rsavitski 25:50805ef8c499 60 max_fv = max_fv * pow(cos(angle_err/2), angle_envelope_exponent);
rsavitski 25:50805ef8c499 61
rsavitski 25:50805ef8c499 62 // constrain range
rsavitski 25:50805ef8c499 63 if (forward_v > max_fv)
rsavitski 25:50805ef8c499 64 forward_v = max_fv;
rsavitski 25:50805ef8c499 65 else if (forward_v < -max_fv)
rsavitski 25:50805ef8c499 66 forward_v = -max_fv;
madcowswe 26:b16f1045108f 67
madcowswe 26:b16f1045108f 68 //printf("fwd: %f, omega: %f\r\n", forward_v, angular_v);
rsavitski 25:50805ef8c499 69
rsavitski 25:50805ef8c499 70 //TODO: put into motor control
rsavitski 25:50805ef8c499 71 MotorControl::set_fwdcmd(forward_v);
madcowswe 26:b16f1045108f 72 MotorControl::set_omegacmd(angular_v);
rsavitski 25:50805ef8c499 73 }
rsavitski 25:50805ef8c499 74
rsavitski 25:50805ef8c499 75 } //namespace