Carbon Fibre / Mbed 2 deprecated Motor_test_harness

Important changes to repositories hosted on mbed.com

Mbed hosted mercurial repositories are deprecated and are due to be permanently deleted in July 2026.

To keep a copy of this software download the repository Zip archive or clone locally using Mercurial.

It is also possible to export all your personal repositories from the account settings page.

Dependencies:   Classic_PID iC_MU mbed-rtos mbed

TiltVelocityLoop.cpp@0:7ce0bc67f60f, 2015-04-02 (annotated)

Committer:
ms523
Date:
Thu Apr 02 07:35:39 2015 +0000
Revision:
0:7ce0bc67f60f
Child:
2:dc684c402296
Working as demo'd in the end of March sprint review.

Who changed what in which revision?

UserRevisionLine numberNew contents of line
ms523 0:7ce0bc67f60f 1 #include "mbed.h"
ms523 0:7ce0bc67f60f 2 #include "iC_MU.h"
ms523 0:7ce0bc67f60f 3 #include "rtos.h"
ms523 0:7ce0bc67f60f 4 #include "Classic_PID.h"
ms523 0:7ce0bc67f60f 5
ms523 0:7ce0bc67f60f 6 // Define limits for zero crossing
ms523 0:7ce0bc67f60f 7 // These values should allow operation upto 3750 RPM
ms523 0:7ce0bc67f60f 8 #define bits 18 // The number of bits we want to use
ms523 0:7ce0bc67f60f 9 #define OneTurn (1<<bits) // 262144 counts per rev
ms523 0:7ce0bc67f60f 10 #define Lower (1<<(bits-5)) // 8192 counts = 11.25 degrees
ms523 0:7ce0bc67f60f 11 #define Upper OneTurn - Lower // 262144 - 8192 = 253952
ms523 0:7ce0bc67f60f 12
ms523 0:7ce0bc67f60f 13 extern iC_MU tilt_ic_mu;
ms523 0:7ce0bc67f60f 14 extern PwmOut Tilt_Motor_PWM;
ms523 0:7ce0bc67f60f 15 extern DigitalOut Tilt_Motor_Direction;
ms523 0:7ce0bc67f60f 16 extern Classic_PID TiltVelocityPID;
ms523 0:7ce0bc67f60f 17
ms523 0:7ce0bc67f60f 18 int LastTiltPosition = 0;
ms523 0:7ce0bc67f60f 19
ms523 0:7ce0bc67f60f 20 void TiltVelocityLoop(void const *args)
ms523 0:7ce0bc67f60f 21 {
ms523 0:7ce0bc67f60f 22 int Position = tilt_ic_mu.ReadPOSITION() >> (19 - bits);// Read the current position from the iC-MU and bitshift to reduce noise
ms523 0:7ce0bc67f60f 23 int Velocity = Position - LastTiltPosition; // Calculate change in position (i.e. Velocity)
ms523 0:7ce0bc67f60f 24 float Duty_Cycle = 0.0;
ms523 0:7ce0bc67f60f 25
ms523 0:7ce0bc67f60f 26 // Check to see if we have gone past the index point
ms523 0:7ce0bc67f60f 27 if(Position < Lower & LastTiltPosition > Upper) { // We have gone over the index point in 1 direction
ms523 0:7ce0bc67f60f 28 Velocity += OneTurn;
ms523 0:7ce0bc67f60f 29 } else if(Position > Upper & LastTiltPosition < Lower) {// We have gone over the index point in the other direction
ms523 0:7ce0bc67f60f 30 Velocity -= OneTurn;
ms523 0:7ce0bc67f60f 31 }
ms523 0:7ce0bc67f60f 32 LastTiltPosition = Position; // Update new position from next time
ms523 0:7ce0bc67f60f 33
ms523 0:7ce0bc67f60f 34 TiltVelocityPID.setProcessValue(Velocity); // Pass the Velocity onto the PID loop
ms523 0:7ce0bc67f60f 35 Duty_Cycle = TiltVelocityPID.compute();
ms523 0:7ce0bc67f60f 36
ms523 0:7ce0bc67f60f 37 if(Duty_Cycle < 0) {
ms523 0:7ce0bc67f60f 38 Tilt_Motor_Direction = 0;
ms523 0:7ce0bc67f60f 39 Tilt_Motor_PWM = 1 - (Duty_Cycle * -1.0);
ms523 0:7ce0bc67f60f 40 } else {
ms523 0:7ce0bc67f60f 41 Tilt_Motor_Direction = 1;
ms523 0:7ce0bc67f60f 42 Tilt_Motor_PWM = 1 - Duty_Cycle;
ms523 0:7ce0bc67f60f 43 }
ms523 0:7ce0bc67f60f 44 }