Unipolar stepper motor operation library

Dependents:   LAB04_Oppgave1 test_stepper Stepper_Motor_Demo StepperMotorUni_Hello ... more

Unipolar stepper motor library

This library generates pulses on 4 digital output pins of the mbed. The pulses are generated by mbed's ticker function.

The mbed pins cannot drive the stepper motor directly. So it requires driver stage for the motor. The circuit may be like following diagram.
The driver stage should be chosen by requirement for the stepper motor.

/media/uploads/okano/unipolar-steppermotor-sample.png


The mbed generates pulses on 4 output pins for external driver stage.
This library can generate 3 types of pulses.

1 phase drive (wave drive) /media/uploads/okano/1phase_drive.gif

2 phase drive /media/uploads/okano/2phase_drive.gif

1-2 phase (half step) drive /media/uploads/okano/halfstep_drive.gif

Components pages

Components pages are available for bipolar and unipolar motor libraries

A bipolar stepper motor driving pulse generator

A unipolar stepper motor driving pulse generator

Committer:
okano
Date:
Tue Apr 21 14:37:52 2015 +0000
Revision:
3:0eec6148e739
Parent:
2:6835e719ff96
Child:
4:6909efe4c8ac
ramp control enabled

Who changed what in which revision?

UserRevisionLine numberNew contents of line
okano 0:5d0abdf92786 1 /** Stepper Motor (Unipolar) control library
okano 0:5d0abdf92786 2 *
okano 0:5d0abdf92786 3 * @class StepperMotorUni
okano 0:5d0abdf92786 4 * @author Tedd OKANO
okano 3:0eec6148e739 5 * @version 1.1
okano 3:0eec6148e739 6 * @date 21-Apr-2015
okano 0:5d0abdf92786 7 *
okano 1:5de3a9848490 8 * Copyright: 2010, 2014, 2015 Tedd OKANO
okano 0:5d0abdf92786 9 * Released under the Apache 2 license License
okano 0:5d0abdf92786 10 *
okano 0:5d0abdf92786 11 * The library that controls stepper motor via motor driver chip
okano 0:5d0abdf92786 12 * This is a driver for a unipolar stepper motor.
okano 0:5d0abdf92786 13 *
okano 0:5d0abdf92786 14 * Example:
okano 0:5d0abdf92786 15 * @code
okano 0:5d0abdf92786 16 * #include "mbed.h"
okano 0:5d0abdf92786 17 * #include "StepperMotorUni.h"
okano 0:5d0abdf92786 18 *
okano 0:5d0abdf92786 19 * StepperMotorUni motor( p26, p25, p24, p23 );
okano 0:5d0abdf92786 20 *
okano 0:5d0abdf92786 21 * int main()
okano 0:5d0abdf92786 22 * {
okano 0:5d0abdf92786 23 * motor.set_pps( 50 );
okano 0:5d0abdf92786 24 *
okano 0:5d0abdf92786 25 * while ( 1 ) {
okano 0:5d0abdf92786 26 * motor.move_steps( 24 );
okano 0:5d0abdf92786 27 * wait( 1 );
okano 0:5d0abdf92786 28 *
okano 0:5d0abdf92786 29 * motor.move_steps( -24 );
okano 0:5d0abdf92786 30 * wait( 1 );
okano 0:5d0abdf92786 31 * }
okano 0:5d0abdf92786 32 * }
okano 0:5d0abdf92786 33 * @endcode
okano 0:5d0abdf92786 34 *
okano 0:5d0abdf92786 35 * version 0.51(27-Nov-2010) // initial version (un-published)
okano 0:5d0abdf92786 36 * version 0.6 (15-Jan-2014) // compatible to LPC1768, LPC11U24 and LPC1114 targets
okano 1:5de3a9848490 37 * version 1.0 (19-Jun-2014) // version 1.0 release
okano 1:5de3a9848490 38 * version 1.0.1 (14-Apr-2015) // API document correction
okano 3:0eec6148e739 39 * version 1.1 (21-Apr-2015) // ramp control function enabled
okano 0:5d0abdf92786 40 */
okano 0:5d0abdf92786 41
okano 0:5d0abdf92786 42 #ifndef MBED_STEPPERMOTOR_UNIPOLAR
okano 0:5d0abdf92786 43 #define MBED_STEPPERMOTOR_UNIPOLAR
okano 0:5d0abdf92786 44
okano 0:5d0abdf92786 45 #include "mbed.h"
okano 0:5d0abdf92786 46
okano 0:5d0abdf92786 47 #define MAX_PPS 100 // pulse per second
okano 0:5d0abdf92786 48
okano 0:5d0abdf92786 49
okano 0:5d0abdf92786 50 class StepperMotorUni
okano 0:5d0abdf92786 51 {
okano 0:5d0abdf92786 52 public:
okano 0:5d0abdf92786 53
okano 0:5d0abdf92786 54 /** Constants for motor rotate mode */
okano 0:5d0abdf92786 55 typedef enum {
okano 0:5d0abdf92786 56 ONE_PHASE, /**< 1 phase operation (default) */
okano 0:5d0abdf92786 57 TWO_PHASE, /**< 2 phase operation */
okano 0:5d0abdf92786 58 HALFSTEP /**< halfstep operation */
okano 0:5d0abdf92786 59 } OperationPhaseMode;
okano 0:5d0abdf92786 60
okano 0:5d0abdf92786 61 /** Constants for motor rotate mode */
okano 0:5d0abdf92786 62 typedef enum {
okano 0:5d0abdf92786 63 SHORTEST, /**< turn by shortest direction (default) */
okano 0:5d0abdf92786 64 NO_WRAPAROUND, /**< do not accross home position */
okano 0:5d0abdf92786 65 CLOCKWISE_ONLY, /**< one-way: clockwise turn */
okano 0:5d0abdf92786 66 COUNTER_CLOCKWISE_ONLY /**< one-way: counter clockwise turn */
okano 0:5d0abdf92786 67 } RotMode;
okano 0:5d0abdf92786 68 /** Constants for syncronization mode */
okano 0:5d0abdf92786 69 typedef enum {
okano 0:5d0abdf92786 70 ASYNCHRONOUS, /**< program does wait motor turn completion (default) */
okano 0:5d0abdf92786 71 SYNCHRONOUS /**< program doesn't wait motor turn completion */
okano 0:5d0abdf92786 72 } SyncMode;
okano 0:5d0abdf92786 73
okano 0:5d0abdf92786 74 /** Constants for position detection edge polarity */
okano 0:5d0abdf92786 75 typedef enum {
okano 0:5d0abdf92786 76 RISING_EDGE, /**< position detection done by rising edge */
okano 0:5d0abdf92786 77 FALLING_EDGE /**< position detection done by falling edge */
okano 0:5d0abdf92786 78 } PositionDetectPorarity;
okano 0:5d0abdf92786 79
okano 0:5d0abdf92786 80 /** Constants for position detection edge polarity */
okano 0:5d0abdf92786 81 typedef enum {
okano 0:5d0abdf92786 82 SOFT_BRAKE, /**< brake with slowing down */
okano 0:5d0abdf92786 83 HARD_BRAKE /**< for immedate stop */
okano 0:5d0abdf92786 84 } BrakeMode;
okano 0:5d0abdf92786 85
okano 0:5d0abdf92786 86 /** Create a stepper motor object connected to specified DigitalOut pins and a DigitalIn pin
okano 0:5d0abdf92786 87 *
okano 0:5d0abdf92786 88 * @param out_A DigitalOut pin for motor pulse signal-A
okano 0:5d0abdf92786 89 * @param out_B DigitalOut pin for motor pulse signal-B
okano 0:5d0abdf92786 90 * @param out_C DigitalOut pin for motor pulse signal-C
okano 0:5d0abdf92786 91 * @param out_D DigitalOut pin for motor pulse signal-D
okano 0:5d0abdf92786 92 * @param position_detect DigitalIn pin for home position detection (option). if not defined, "find_home_position()" function cannot be used
okano 0:5d0abdf92786 93 */
okano 0:5d0abdf92786 94 StepperMotorUni(
okano 0:5d0abdf92786 95 PinName out_A,
okano 0:5d0abdf92786 96 PinName out_B,
okano 0:5d0abdf92786 97 PinName out_C,
okano 0:5d0abdf92786 98 PinName out_D,
okano 0:5d0abdf92786 99 PinName position_detect = NC
okano 0:5d0abdf92786 100 ) ;
okano 0:5d0abdf92786 101
okano 0:5d0abdf92786 102 /** Set the pulse width (i.e. motor turning speed)
okano 0:5d0abdf92786 103 *
okano 0:5d0abdf92786 104 * @param v pulse per second (pps) : lower number makes the turn slower (default = 100)
okano 0:5d0abdf92786 105 */
okano 0:5d0abdf92786 106 float set_pps( float v );
okano 0:5d0abdf92786 107
okano 0:5d0abdf92786 108 /** Set maximum PPS (= minimum pulse width) which will be used in finding home position
okano 0:5d0abdf92786 109 *
okano 0:5d0abdf92786 110 * @param v maximum pulse per second : lower number makes the turn slower (default = 100)
okano 0:5d0abdf92786 111 */
okano 0:5d0abdf92786 112 void set_max_pps( float v );
okano 0:5d0abdf92786 113
okano 0:5d0abdf92786 114 /** Find home position: rotate the motor until the detection edge comes.
okano 0:5d0abdf92786 115 *
okano 0:5d0abdf92786 116 * Turns the motor until the home position detected.
okano 0:5d0abdf92786 117 * The "home position" is a reference point for the step and angle. It will be step=0 and angle=0.
okano 0:5d0abdf92786 118 * The detection signal edge can be defined by an argument.
okano 0:5d0abdf92786 119 * It follows the rotate mode.
okano 0:5d0abdf92786 120 * When the edge is detected, the motor will be stopped and it will be the new home position.
okano 0:5d0abdf92786 121 * If no detection signal detected, no home position update done.
okano 0:5d0abdf92786 122 *
okano 0:5d0abdf92786 123 * @param edge defines detection edge rise or fall
okano 0:5d0abdf92786 124 */
okano 0:5d0abdf92786 125 int find_home_position( PositionDetectPorarity edge );
okano 0:5d0abdf92786 126
okano 0:5d0abdf92786 127 /** Update home position
okano 0:5d0abdf92786 128 *
okano 0:5d0abdf92786 129 * Set the home position as current motor position.
okano 0:5d0abdf92786 130 */
okano 0:5d0abdf92786 131 void set_home_position( void );
okano 0:5d0abdf92786 132
okano 0:5d0abdf92786 133 /** Turn the motor to defined position (by steps from home position)
okano 0:5d0abdf92786 134 *
okano 0:5d0abdf92786 135 * Make motor move to absolute position
okano 0:5d0abdf92786 136 *
okano 0:5d0abdf92786 137 * @param v the position defined by steps from home position
okano 0:5d0abdf92786 138 */
okano 0:5d0abdf92786 139 int go_position( int v );
okano 0:5d0abdf92786 140
okano 0:5d0abdf92786 141 /** Turn the motor to defined position (by angle (degree)) from home position)
okano 0:5d0abdf92786 142 *
okano 0:5d0abdf92786 143 * Make motor move to absolute position
okano 0:5d0abdf92786 144 *
okano 0:5d0abdf92786 145 * @param v the position defined by steps from home position
okano 0:5d0abdf92786 146 */
okano 0:5d0abdf92786 147 void go_angle( float angle );
okano 0:5d0abdf92786 148
okano 0:5d0abdf92786 149 /** Turn the motor to defined position (by steps from current position)
okano 0:5d0abdf92786 150 *
okano 0:5d0abdf92786 151 * Make motor move to defined position
okano 0:5d0abdf92786 152 *
okano 0:5d0abdf92786 153 * @param v the position defined by steps from current position
okano 0:5d0abdf92786 154 */
okano 0:5d0abdf92786 155 int move_steps( int s );
okano 0:5d0abdf92786 156
okano 0:5d0abdf92786 157 /** Turn the motor to defined rotation (from current position)
okano 0:5d0abdf92786 158 *
okano 0:5d0abdf92786 159 * Make motor rotate
okano 0:5d0abdf92786 160 *
okano 0:5d0abdf92786 161 * @param r number of rotation start from current position
okano 0:5d0abdf92786 162 */
okano 0:5d0abdf92786 163 int move_rotates( float r );
okano 0:5d0abdf92786 164
okano 0:5d0abdf92786 165 /** Interface for opertion phase mode setting
okano 0:5d0abdf92786 166 *
okano 1:5de3a9848490 167 * @param v Driving phase mode change : ONE_PHASE (default), TWO_PHASE or HALFSTEP
okano 0:5d0abdf92786 168 */
okano 0:5d0abdf92786 169 void set_operation_phase_mode( OperationPhaseMode v );
okano 0:5d0abdf92786 170
okano 0:5d0abdf92786 171 /** Interface for motor rotate mode setting
okano 0:5d0abdf92786 172 *
okano 0:5d0abdf92786 173 * Example:
okano 0:5d0abdf92786 174 * @code
okano 0:5d0abdf92786 175 * StepperMotor m( p21, p22, p23, p24 );
okano 0:5d0abdf92786 176 * int main() {
okano 0:5d0abdf92786 177 * m.set_rot_mode( StepperMotor::NO_WRAPAROUND );
okano 0:5d0abdf92786 178 * ...
okano 0:5d0abdf92786 179 * @endcode
okano 0:5d0abdf92786 180 *
okano 0:5d0abdf92786 181 * @param m motor rotate mode : SHORTEST (default), NO_WRAPAROUND, CLOCKWISE_ONLY or COUNTER_CLOCKWISE_ONLY
okano 0:5d0abdf92786 182 */
okano 0:5d0abdf92786 183
okano 0:5d0abdf92786 184 void set_rot_mode( RotMode m );
okano 0:5d0abdf92786 185
okano 0:5d0abdf92786 186 /** Interface for syncronization mode setting
okano 0:5d0abdf92786 187 *
okano 0:5d0abdf92786 188 * Example:
okano 0:5d0abdf92786 189 * @code
okano 0:5d0abdf92786 190 * StepperMotor m( p21, p22, p23, p24 );
okano 0:5d0abdf92786 191 * int main() {
okano 0:5d0abdf92786 192 * m.set_sync_mode( StepperMotor::NO_WRAPAROUND );
okano 0:5d0abdf92786 193 * ...
okano 0:5d0abdf92786 194 * @endcode
okano 0:5d0abdf92786 195 *
okano 0:5d0abdf92786 196 * @param m motor rotate mode : ASYNCHRONOUS (default) or SYNCHRONOUS
okano 0:5d0abdf92786 197 */
okano 0:5d0abdf92786 198 void set_sync_mode( SyncMode m );
okano 0:5d0abdf92786 199
okano 0:5d0abdf92786 200 /** Check remaining distance that motor need to move
okano 0:5d0abdf92786 201 *
okano 0:5d0abdf92786 202 * software can check if the motor action completed in asynchronous mode
okano 0:5d0abdf92786 203 *
okano 0:5d0abdf92786 204 * @return remaining steps that motor need to go
okano 0:5d0abdf92786 205 */
okano 0:5d0abdf92786 206 int distance( void );
okano 0:5d0abdf92786 207
okano 0:5d0abdf92786 208 /** Pause/Resume the motor action
okano 0:5d0abdf92786 209 *
okano 0:5d0abdf92786 210 * @param sw use "true" for pause, "false" (default) for resume
okano 0:5d0abdf92786 211 */
okano 0:5d0abdf92786 212 void set_pause( int sw );
okano 0:5d0abdf92786 213
okano 0:5d0abdf92786 214 /** Pause/Resume the motor action
okano 0:5d0abdf92786 215 *
okano 0:5d0abdf92786 216 * @param sw use "true" for pause, "false" (default) for resume
okano 0:5d0abdf92786 217 */
okano 0:5d0abdf92786 218 void brake( void );
okano 0:5d0abdf92786 219 void brake( BrakeMode mode );
okano 0:5d0abdf92786 220
okano 0:5d0abdf92786 221 /** Auto power control enable
okano 0:5d0abdf92786 222 *
okano 0:5d0abdf92786 223 * If the auto power control is enabled, the motor power will be turned-off when it stays same place
okano 0:5d0abdf92786 224 *
okano 0:5d0abdf92786 225 * @param sw use "true" for pause, "false" (default) for resume
okano 0:5d0abdf92786 226 */
okano 0:5d0abdf92786 227 void set_power_ctrl( int sw );
okano 0:5d0abdf92786 228
okano 0:5d0abdf92786 229 /** Setting for steps/rotate
okano 0:5d0abdf92786 230 *
okano 0:5d0abdf92786 231 * This parameter is required if program want to use the "go_angle()" interface.
okano 0:5d0abdf92786 232 * The angle will be calculated from this parameter.
okano 0:5d0abdf92786 233 *
okano 0:5d0abdf92786 234 * @param steps per rotate
okano 0:5d0abdf92786 235 */
okano 0:5d0abdf92786 236 void set_steps_per_rotate( int steps );
okano 0:5d0abdf92786 237
okano 2:6835e719ff96 238 /** Setting for ramp control
okano 2:6835e719ff96 239 *
okano 2:6835e719ff96 240 * This function enables the ramp-up and ramp-down of the motor behavior
okano 2:6835e719ff96 241 *
okano 2:6835e719ff96 242 * @param initial_speed_rate speed rate. if the pps was set to 50pps and
okano 2:6835e719ff96 243 * initial_speed_rate is given like 0.1, the ramp-up-start and ramp-dowm-end
okano 2:6835e719ff96 244 * speed will be 5pps (= 0.1 * 50pps)
okano 2:6835e719ff96 245 * @param ramp_steps the steps for ramp-up and ramp-down.
okano 2:6835e719ff96 246 */
okano 0:5d0abdf92786 247 void set_ramp_control( float initial_speed_rate, int ramp_steps );
okano 2:6835e719ff96 248
okano 0:5d0abdf92786 249 private:
okano 0:5d0abdf92786 250
okano 0:5d0abdf92786 251 Ticker t;
okano 0:5d0abdf92786 252 BusOut motor_out;
okano 0:5d0abdf92786 253 DigitalIn position_detect_pin;
okano 0:5d0abdf92786 254
okano 0:5d0abdf92786 255 static unsigned char pattern_one_phase[ 4 ]; // 1 phase pulse pattern for motor control
okano 0:5d0abdf92786 256 static unsigned char pattern_two_phase[ 4 ]; // 1 phase pulse pattern for motor control
okano 0:5d0abdf92786 257 static unsigned char pattern_halfstep[ 8 ]; // 1 phase pulse pattern for motor control
okano 0:5d0abdf92786 258 unsigned char *pattern;
okano 0:5d0abdf92786 259 int pat_index_mask;
okano 0:5d0abdf92786 260 OperationPhaseMode phase_mode;
okano 0:5d0abdf92786 261 RotMode rot_mode;
okano 0:5d0abdf92786 262 SyncMode sync_mode;
okano 0:5d0abdf92786 263 int max_pos;
okano 0:5d0abdf92786 264 int current_pos;
okano 0:5d0abdf92786 265 int pos_offset;
okano 0:5d0abdf92786 266 int target_pos;
okano 0:5d0abdf92786 267 float pps;
okano 0:5d0abdf92786 268 float max_pps;
okano 0:5d0abdf92786 269 int init_done;
okano 0:5d0abdf92786 270 int pause;
okano 0:5d0abdf92786 271 int power_ctrl;
okano 0:5d0abdf92786 272 float ramp_init_speed_rate;
okano 0:5d0abdf92786 273 int ramp_control_steps;
okano 0:5d0abdf92786 274 float ramp_rate;
okano 0:5d0abdf92786 275
okano 0:5d0abdf92786 276 void set_target_pos( int p ); // target position setting interface
okano 0:5d0abdf92786 277 void motor_maintain( void ); // this function is called periodically by Ticker
okano 0:5d0abdf92786 278 };
okano 0:5d0abdf92786 279
okano 0:5d0abdf92786 280
okano 0:5d0abdf92786 281 #endif