St Knz
P2
Revision 0:bb408887ab78, committed 2018-03-09
- Comitter:
- kueenste
- Date:
- Fri Mar 09 15:29:36 2018 +0000
- Commit message:
- P2_unfertig;
Changed in this revision
diff -r 000000000000 -r bb408887ab78 Controller.cpp
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/Controller.cpp Fri Mar 09 15:29:36 2018 +0000
@@ -0,0 +1,175 @@
+/*
+ * Controller.cpp
+ * Copyright (c) 2018, ZHAW
+ * All rights reserved.
+ */
+
+#include <cmath>
+#include "Controller.h"
+
+using namespace std;
+
+const float Controller::PERIOD = 0.001f; // period of control task, given in [s]
+const float Controller::COUNTS_PER_TURN = 1200.0f; // resolution of encoder counter
+const float Controller::LOWPASS_FILTER_FREQUENCY = 300.0f; // frequency of lowpass filter for actual speed values, given in [rad/s]
+const float Controller::KN = 40.0f; // speed constant of motor, given in [rpm/V]
+const float Controller::KP = 0.2f; // speed controller gain, given in [V/rpm]
+const float Controller::MAX_VOLTAGE = 12.0f; // supply voltage for power stage in [V]
+const float Controller::MIN_DUTY_CYCLE = 0.02f; // minimum allowed value for duty cycle (2%)
+const float Controller::MAX_DUTY_CYCLE = 0.98f; // maximum allowed value for duty cycle (98%)
+
+const float Controller::R = 0.17f/2.0f; // Abstand Antriebsraeder zu Mitte
+const float Controller::r = 0.0375f; // Radius der Antriebsraeder
+
+/**
+ * Creates and initializes a Controller object.
+ * @param pwmLeft a pwm output object to set the duty cycle for the left motor.
+ * @param pwmRight a pwm output object to set the duty cycle for the right motor.
+ * @param counterLeft an encoder counter object to read the position of the left motor.
+ * @param counterRight an encoder counter object to read the position of the right motor.
+ */
+Controller::Controller(PwmOut& pwmLeft, PwmOut& pwmRight, EncoderCounter& counterLeft, EncoderCounter& counterRight) : pwmLeft(pwmLeft), pwmRight(pwmRight), counterLeft(counterLeft), counterRight(counterRight) {
+
+ // initialize periphery drivers
+
+ pwmLeft.period(0.00005f);
+ pwmLeft.write(0.5f);
+
+ pwmRight.period(0.00005f);
+ pwmRight.write(0.5f);
+
+ // initialize local variables
+
+ translationalMotion.setProfileVelocity(3.0f);
+ translationalMotion.setProfileAcceleration(1.0f);
+ translationalMotion.setProfileDeceleration(1.0f);
+
+ rotationalMotion.setProfileVelocity(2.0f);
+ rotationalMotion.setProfileAcceleration(2.0f);
+ rotationalMotion.setProfileDeceleration(2.0f);
+
+ translationalVelocity = 0.0f;
+ rotationalVelocity = 0.0f;
+ actualTranslationalVelocity = 0.0f;
+ actualRotationalVelocity = 0.0f;
+
+ previousValueCounterLeft = counterLeft.read();
+ previousValueCounterRight = counterRight.read();
+
+ speedLeftFilter.setPeriod(PERIOD);
+ speedLeftFilter.setFrequency(LOWPASS_FILTER_FREQUENCY);
+
+ speedRightFilter.setPeriod(PERIOD);
+ speedRightFilter.setFrequency(LOWPASS_FILTER_FREQUENCY);
+
+ desiredSpeedLeft = 0.0f;
+ desiredSpeedRight = 0.0f;
+
+ actualSpeedLeft = 0.0f;
+ actualSpeedRight = 0.0f;
+
+ // start periodic task
+
+ ticker.attach(callback(this, &Controller::run), PERIOD);
+}
+
+/**
+ * Deletes the Controller object and releases all allocated resources.
+ */
+Controller::~Controller() {
+
+ ticker.detach();
+}
+
+/**
+ * Sets the desired translational velocity of the robot.
+ * @param velocity the desired translational velocity, given in [m/s].
+ */
+void Controller::setTranslationalVelocity(float velocity) {
+
+ this->translationalVelocity = velocity;
+}
+
+/**
+ * Sets the desired rotational velocity of the robot.
+ * @param velocity the desired rotational velocity, given in [rad/s].
+ */
+void Controller::setRotationalVelocity(float velocity) {
+
+ this->rotationalVelocity = velocity;
+}
+
+/**
+ * Gets the actual translational velocity of the robot.
+ * @return the actual translational velocity, given in [m/s].
+ */
+float Controller::getActualTranslationalVelocity() {
+
+ return actualTranslationalVelocity;
+}
+
+/**
+ * Gets the actual rotational velocity of the robot.
+ * @return the actual rotational velocity, given in [rad/s].
+ */
+float Controller::getActualRotationalVelocity() {
+
+ return actualRotationalVelocity;
+}
+
+/**
+ * This method is called periodically by the ticker object and contains the
+ * algorithm of the speed controller.
+ */
+void Controller::run() {
+
+ // calculate the planned velocities using the motion planner
+
+ translationalMotion.incrementToVelocity(translationalVelocity,PERIOD);
+ rotationalMotion.incrementToVelocity(rotationalVelocity,PERIOD);
+
+
+ // calculate the values 'desiredSpeedLeft' and 'desiredSpeedRight' using the kinematic model
+
+ desiredSpeedLeft = 60.0f*(translationalMotion.getVelocity() - R*rotationalMotion.getVelocity())/(2.0f*3.14159f*r);
+ // rad rechts muss invertiert werden für VORWAERTS
+ desiredSpeedRight = 60.0f*(-1*(translationalMotion.getVelocity() + R*rotationalMotion.getVelocity()))/(2.0f*3.14159f*r);
+
+ // calculate actual speed of motors in [rpm]
+
+ short valueCounterLeft = counterLeft.read();
+ short valueCounterRight = counterRight.read();
+
+ short countsInPastPeriodLeft = valueCounterLeft-previousValueCounterLeft;
+ short countsInPastPeriodRight = valueCounterRight-previousValueCounterRight;
+
+ previousValueCounterLeft = valueCounterLeft;
+ previousValueCounterRight = valueCounterRight;
+
+ actualSpeedLeft = speedLeftFilter.filter((float)countsInPastPeriodLeft/COUNTS_PER_TURN/PERIOD*60.0f);
+ actualSpeedRight = speedRightFilter.filter((float)countsInPastPeriodRight/COUNTS_PER_TURN/PERIOD*60.0f);
+
+ // calculate motor phase voltages
+
+ float voltageLeft = KP*(desiredSpeedLeft-actualSpeedLeft)+desiredSpeedLeft/KN;
+ float voltageRight = KP*(desiredSpeedRight-actualSpeedRight)+desiredSpeedRight/KN;
+
+ // calculate, limit and set duty cycles
+
+ float dutyCycleLeft = 0.5f+0.5f*voltageLeft/MAX_VOLTAGE;
+ if (dutyCycleLeft < MIN_DUTY_CYCLE) dutyCycleLeft = MIN_DUTY_CYCLE;
+ else if (dutyCycleLeft > MAX_DUTY_CYCLE) dutyCycleLeft = MAX_DUTY_CYCLE;
+ pwmLeft.write(dutyCycleLeft);
+
+ float dutyCycleRight = 0.5f+0.5f*voltageRight/MAX_VOLTAGE;
+ if (dutyCycleRight < MIN_DUTY_CYCLE) dutyCycleRight = MIN_DUTY_CYCLE;
+ else if (dutyCycleRight > MAX_DUTY_CYCLE) dutyCycleRight = MAX_DUTY_CYCLE;
+ pwmRight.write(dutyCycleRight);
+
+ // calculate the values 'actualTranslationalVelocity' and 'actualRotationalVelocity' using the kinematic model
+
+ //actualTranslationalVelocity = 0.5f * r *(actualSpeedLeft+actualSpeedRight);
+ //actualRotationalVelocity = 0.5f /R*r*(actualSpeedLeft+actualSpeedRight);
+
+}
+
diff -r 000000000000 -r bb408887ab78 Controller.h
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/Controller.h Fri Mar 09 15:29:36 2018 +0000
@@ -0,0 +1,70 @@
+/*
+ * Controller.h
+ * Copyright (c) 2018, ZHAW
+ * All rights reserved.
+ */
+
+#ifndef CONTROLLER_H_
+#define CONTROLLER_H_
+
+#include <cstdlib>
+#include <mbed.h>
+#include "EncoderCounter.h"
+#include "Motion.h"
+#include "LowpassFilter.h"
+
+/**
+ * This class implements the coordinate transformation, speed control and
+ * the position estimation of a mobile robot with differential drive.
+ */
+class Controller {
+
+ public:
+
+ Controller(PwmOut& pwmLeft, PwmOut& pwmRight, EncoderCounter& counterLeft, EncoderCounter& counterRight);
+ virtual ~Controller();
+ void setTranslationalVelocity(float velocity);
+ void setRotationalVelocity(float velocity);
+ float getActualTranslationalVelocity();
+ float getActualRotationalVelocity();
+
+ private:
+
+ static const float PERIOD;
+ static const float COUNTS_PER_TURN;
+ static const float LOWPASS_FILTER_FREQUENCY;
+ static const float KN;
+ static const float KP;
+ static const float MAX_VOLTAGE;
+ static const float MIN_DUTY_CYCLE;
+ static const float MAX_DUTY_CYCLE;
+
+ static const float R;
+ static const float r;
+
+ PwmOut& pwmLeft;
+ PwmOut& pwmRight;
+ EncoderCounter& counterLeft;
+ EncoderCounter& counterRight;
+ Motion translationalMotion;
+ Motion rotationalMotion;
+ float translationalVelocity;
+ float rotationalVelocity;
+ float actualTranslationalVelocity;
+ float actualRotationalVelocity;
+ short previousValueCounterLeft;
+ short previousValueCounterRight;
+ LowpassFilter speedLeftFilter;
+ LowpassFilter speedRightFilter;
+ float desiredSpeedLeft;
+ float desiredSpeedRight;
+ float actualSpeedLeft;
+ float actualSpeedRight;
+ Ticker ticker;
+
+
+ void run();
+};
+
+#endif /* CONTROLLER_H_ */
+
diff -r 000000000000 -r bb408887ab78 EncoderCounter.cpp
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/EncoderCounter.cpp Fri Mar 09 15:29:36 2018 +0000
@@ -0,0 +1,169 @@
+/*
+ * EncoderCounter.cpp
+ * Copyright (c) 2018, ZHAW
+ * All rights reserved.
+ */
+
+#include "EncoderCounter.h"
+
+using namespace std;
+
+/**
+ * Creates and initializes the driver to read the quadrature
+ * encoder counter of the STM32 microcontroller.
+ * @param a the input pin for the channel A.
+ * @param b the input pin for the channel B.
+ */
+EncoderCounter::EncoderCounter(PinName a, PinName b) {
+
+ // check pins
+
+ if ((a == PA_0) && (b == PA_1)) {
+
+ // pinmap OK for TIM2 CH1 and CH2
+
+ TIM = TIM2;
+
+ // configure general purpose I/O registers
+
+ GPIOA->MODER &= ~GPIO_MODER_MODER0; // reset port A0
+ GPIOA->MODER |= GPIO_MODER_MODER0_1; // set alternate mode of port A0
+ GPIOA->PUPDR &= ~GPIO_PUPDR_PUPDR0; // reset pull-up/pull-down on port A0
+ GPIOA->PUPDR |= GPIO_PUPDR_PUPDR0_1; // set input as pull-down
+ GPIOA->AFR[0] &= ~(0xF << 4*0); // reset alternate function of port A0
+ GPIOA->AFR[0] |= 1 << 4*0; // set alternate funtion 1 of port A0
+
+ GPIOA->MODER &= ~GPIO_MODER_MODER1; // reset port A1
+ GPIOA->MODER |= GPIO_MODER_MODER1_1; // set alternate mode of port A1
+ GPIOA->PUPDR &= ~GPIO_PUPDR_PUPDR1; // reset pull-up/pull-down on port A1
+ GPIOA->PUPDR |= GPIO_PUPDR_PUPDR1_1; // set input as pull-down
+ GPIOA->AFR[0] &= ~(0xF << 4*1); // reset alternate function of port A1
+ GPIOA->AFR[0] |= 1 << 4*1; // set alternate funtion 1 of port A1
+
+ // configure reset and clock control registers
+
+ RCC->APB1RSTR |= RCC_APB1RSTR_TIM2RST; //reset TIM2 controller
+ RCC->APB1RSTR &= ~RCC_APB1RSTR_TIM2RST;
+
+ RCC->APB1ENR |= RCC_APB1ENR_TIM2EN; // TIM2 clock enable
+
+ } else if ((a == PA_6) && (b == PC_7)) {
+
+ // pinmap OK for TIM3 CH1 and CH2
+
+ TIM = TIM3;
+
+ // configure reset and clock control registers
+
+ RCC->AHB1ENR |= RCC_AHB1ENR_GPIOCEN; // manually enable port C (port A enabled by mbed library)
+
+ // configure general purpose I/O registers
+
+ GPIOA->MODER &= ~GPIO_MODER_MODER6; // reset port A6
+ GPIOA->MODER |= GPIO_MODER_MODER6_1; // set alternate mode of port A6
+ GPIOA->PUPDR &= ~GPIO_PUPDR_PUPDR6; // reset pull-up/pull-down on port A6
+ GPIOA->PUPDR |= GPIO_PUPDR_PUPDR6_1; // set input as pull-down
+ GPIOA->AFR[0] &= ~(0xF << 4*6); // reset alternate function of port A6
+ GPIOA->AFR[0] |= 2 << 4*6; // set alternate funtion 2 of port A6
+
+ GPIOC->MODER &= ~GPIO_MODER_MODER7; // reset port C7
+ GPIOC->MODER |= GPIO_MODER_MODER7_1; // set alternate mode of port C7
+ GPIOC->PUPDR &= ~GPIO_PUPDR_PUPDR7; // reset pull-up/pull-down on port C7
+ GPIOC->PUPDR |= GPIO_PUPDR_PUPDR7_1; // set input as pull-down
+ GPIOC->AFR[0] &= ~0xF0000000; // reset alternate function of port C7
+ GPIOC->AFR[0] |= 2 << 4*7; // set alternate funtion 2 of port C7
+
+ // configure reset and clock control registers
+
+ RCC->APB1RSTR |= RCC_APB1RSTR_TIM3RST; //reset TIM3 controller
+ RCC->APB1RSTR &= ~RCC_APB1RSTR_TIM3RST;
+
+ RCC->APB1ENR |= RCC_APB1ENR_TIM3EN; // TIM3 clock enable
+
+ } else if ((a == PB_6) && (b == PB_7)) {
+
+ // pinmap OK for TIM4 CH1 and CH2
+
+ TIM = TIM4;
+
+ // configure reset and clock control registers
+
+ RCC->AHB1ENR |= RCC_AHB1ENR_GPIOBEN; // manually enable port B (port A enabled by mbed library)
+
+ // configure general purpose I/O registers
+
+ GPIOB->MODER &= ~GPIO_MODER_MODER6; // reset port B6
+ GPIOB->MODER |= GPIO_MODER_MODER6_1; // set alternate mode of port B6
+ GPIOB->PUPDR &= ~GPIO_PUPDR_PUPDR6; // reset pull-up/pull-down on port B6
+ GPIOB->PUPDR |= GPIO_PUPDR_PUPDR6_1; // set input as pull-down
+ GPIOB->AFR[0] &= ~(0xF << 4*6); // reset alternate function of port B6
+ GPIOB->AFR[0] |= 2 << 4*6; // set alternate funtion 2 of port B6
+
+ GPIOB->MODER &= ~GPIO_MODER_MODER7; // reset port B7
+ GPIOB->MODER |= GPIO_MODER_MODER7_1; // set alternate mode of port B7
+ GPIOB->PUPDR &= ~GPIO_PUPDR_PUPDR7; // reset pull-up/pull-down on port B7
+ GPIOB->PUPDR |= GPIO_PUPDR_PUPDR7_1; // set input as pull-down
+ GPIOB->AFR[0] &= ~0xF0000000; // reset alternate function of port B7
+ GPIOB->AFR[0] |= 2 << 4*7; // set alternate funtion 2 of port B7
+
+ // configure reset and clock control registers
+
+ RCC->APB1RSTR |= RCC_APB1RSTR_TIM4RST; //reset TIM4 controller
+ RCC->APB1RSTR &= ~RCC_APB1RSTR_TIM4RST;
+
+ RCC->APB1ENR |= RCC_APB1ENR_TIM4EN; // TIM4 clock enable
+
+ } else {
+
+ printf("pinmap not found for peripheral\n");
+ }
+
+ // configure general purpose timer 3 or 4
+
+ TIM->CR1 = 0x0000; // counter disable
+ TIM->CR2 = 0x0000; // reset master mode selection
+ TIM->SMCR = TIM_SMCR_SMS_1 | TIM_SMCR_SMS_0; // counting on both TI1 & TI2 edges
+ TIM->CCMR1 = TIM_CCMR1_CC2S_0 | TIM_CCMR1_CC1S_0;
+ TIM->CCMR2 = 0x0000; // reset capture mode register 2
+ TIM->CCER = TIM_CCER_CC2E | TIM_CCER_CC1E;
+ TIM->CNT = 0x0000; // reset counter value
+ TIM->ARR = 0xFFFF; // auto reload register
+ TIM->CR1 = TIM_CR1_CEN; // counter enable
+}
+
+EncoderCounter::~EncoderCounter() {}
+
+/**
+ * Resets the counter value to zero.
+ */
+void EncoderCounter::reset() {
+
+ TIM->CNT = 0x0000;
+}
+
+/**
+ * Resets the counter value to a given offset value.
+ * @param offset the offset value to reset the counter to.
+ */
+void EncoderCounter::reset(short offset) {
+
+ TIM->CNT = -offset;
+}
+
+/**
+ * Reads the quadrature encoder counter value.
+ * @return the quadrature encoder counter as a signed 16-bit integer value.
+ */
+short EncoderCounter::read() {
+
+ return (short)(-TIM->CNT);
+}
+
+/**
+ * The empty operator is a shorthand notation of the <code>read()</code> method.
+ */
+EncoderCounter::operator short() {
+
+ return read();
+}
+
diff -r 000000000000 -r bb408887ab78 EncoderCounter.h
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/EncoderCounter.h Fri Mar 09 15:29:36 2018 +0000
@@ -0,0 +1,34 @@
+/*
+ * EncoderCounter.h
+ * Copyright (c) 2018, ZHAW
+ * All rights reserved.
+ */
+
+#ifndef ENCODER_COUNTER_H_
+#define ENCODER_COUNTER_H_
+
+#include <cstdlib>
+#include <mbed.h>
+
+/**
+ * This class implements a driver to read the quadrature
+ * encoder counter of the STM32 microcontroller.
+ */
+class EncoderCounter {
+
+ public:
+
+ EncoderCounter(PinName a, PinName b);
+ virtual ~EncoderCounter();
+ void reset();
+ void reset(short offset);
+ short read();
+ operator short();
+
+ private:
+
+ TIM_TypeDef* TIM;
+};
+
+#endif /* ENCODER_COUNTER_H_ */
+
diff -r 000000000000 -r bb408887ab78 IRSensor.cpp
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/IRSensor.cpp Fri Mar 09 15:29:36 2018 +0000
@@ -0,0 +1,54 @@
+/*
+ * IRSensor.cpp
+ * Copyright (c) 2018, ZHAW
+ * All rights reserved.
+ */
+
+#include <cmath>
+#include "IRSensor.h"
+
+using namespace std;
+
+/**
+ * Creates an IRSensor object.
+ * @param distance an analog input object to read the voltage of the sensor.
+ * @param bit0 a digital output to set the first bit of the multiplexer.
+ * @param bit1 a digital output to set the second bit of the multiplexer.
+ * @param bit2 a digital output to set the third bit of the multiplexer.
+ * @param number the number of the sensor, either 0, 1, 2, 3, 4 or 5.
+ */
+IRSensor::IRSensor(AnalogIn& distance, DigitalOut& bit0, DigitalOut& bit1, DigitalOut& bit2, int number) : distance(distance), bit0(bit0), bit1(bit1), bit2(bit2) {
+
+ // set local references to objects
+
+ this->number = number;
+}
+
+/**
+ * Deletes the IRSensor object.
+ */
+IRSensor::~IRSensor() {}
+
+/**
+ * Gets the distance measured with the IR sensor in [m].
+ * @return the distance, given in [m].
+ */
+float IRSensor::read() {
+
+ bit0 = (number >> 0) & 1;
+ bit1 = (number >> 1) & 1;
+ bit2 = (number >> 2) & 1;
+
+ float d = -0.58f*sqrt(distance)+0.58f; // calculate the distance in [m]
+
+ return d;
+}
+
+/**
+ * The empty operator is a shorthand notation of the <code>read()</code> method.
+ */
+IRSensor::operator float() {
+
+ return read();
+}
+
diff -r 000000000000 -r bb408887ab78 IRSensor.h
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/IRSensor.h Fri Mar 09 15:29:36 2018 +0000
@@ -0,0 +1,36 @@
+/*
+ * IRSensor.h
+ * Copyright (c) 2018, ZHAW
+ * All rights reserved.
+ */
+
+#ifndef IR_SENSOR_H_
+#define IR_SENSOR_H_
+
+#include <cstdlib>
+#include <mbed.h>
+
+/**
+ * This is a device driver class to read the distance measured with a Sharp IR sensor.
+ */
+class IRSensor {
+
+ public:
+
+ IRSensor(AnalogIn& distance, DigitalOut& bit0, DigitalOut& bit1, DigitalOut& bit2, int number);
+ virtual ~IRSensor();
+ float read();
+ operator float();
+
+ private:
+
+ AnalogIn& distance;
+ DigitalOut& bit0;
+ DigitalOut& bit1;
+ DigitalOut& bit2;
+
+ int number;
+};
+
+#endif /* IR_SENSOR_H_ */
+
diff -r 000000000000 -r bb408887ab78 LowpassFilter.cpp
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/LowpassFilter.cpp Fri Mar 09 15:29:36 2018 +0000
@@ -0,0 +1,112 @@
+/*
+ * LowpassFilter.cpp
+ * Copyright (c) 2018, ZHAW
+ * All rights reserved.
+ */
+
+#include <cmath>
+#include "LowpassFilter.h"
+
+using namespace std;
+
+/**
+ * Creates a LowpassFilter object with a default cutoff frequency of 1000 [rad/s].
+ */
+LowpassFilter::LowpassFilter() {
+
+ period = 1.0f;
+ frequency = 1000.0f;
+
+ a11 = (1.0f+frequency*period)*exp(-frequency*period);
+ a12 = period*exp(-frequency*period);
+ a21 = -frequency*frequency*period*exp(-frequency*period);
+ a22 = (1.0f-frequency*period)*exp(-frequency*period);
+ b1 = (1.0f-(1.0f+frequency*period)*exp(-frequency*period))/frequency/frequency;
+ b2 = period*exp(-frequency*period);
+
+ x1 = 0.0f;
+ x2 = 0.0f;
+}
+
+/**
+ * Deletes the LowpassFilter object.
+ */
+LowpassFilter::~LowpassFilter() {}
+
+/**
+ * Resets the filtered value to zero.
+ */
+void LowpassFilter::reset() {
+
+ x1 = 0.0f;
+ x2 = 0.0f;
+}
+
+/**
+ * Resets the filtered value to a given value.
+ * @param value the value to reset the filter to.
+ */
+void LowpassFilter::reset(float value) {
+
+ x1 = value/frequency/frequency;
+ x2 = (x1-a11*x1-b1*value)/a12;
+}
+
+/**
+ * Sets the sampling period of the filter.
+ * This is typically the sampling period of the periodic task of a controller that uses this filter.
+ * @param the sampling period, given in [s].
+ */
+void LowpassFilter::setPeriod(float period) {
+
+ this->period = period;
+
+ a11 = (1.0f+frequency*period)*exp(-frequency*period);
+ a12 = period*exp(-frequency*period);
+ a21 = -frequency*frequency*period*exp(-frequency*period);
+ a22 = (1.0f-frequency*period)*exp(-frequency*period);
+ b1 = (1.0f-(1.0f+frequency*period)*exp(-frequency*period))/frequency/frequency;
+ b2 = period*exp(-frequency*period);
+}
+
+/**
+ * Sets the cutoff frequency of this filter.
+ * @param frequency the cutoff frequency of the filter in [rad/s].
+ */
+void LowpassFilter::setFrequency(float frequency) {
+
+ this->frequency = frequency;
+
+ a11 = (1.0f+frequency*period)*exp(-frequency*period);
+ a12 = period*exp(-frequency*period);
+ a21 = -frequency*frequency*period*exp(-frequency*period);
+ a22 = (1.0f-frequency*period)*exp(-frequency*period);
+ b1 = (1.0f-(1.0f+frequency*period)*exp(-frequency*period))/frequency/frequency;
+ b2 = period*exp(-frequency*period);
+}
+
+/**
+ * Gets the current cutoff frequency of this filter.
+ * @return the current cutoff frequency in [rad/s].
+ */
+float LowpassFilter::getFrequency() {
+
+ return frequency;
+}
+
+/**
+ * Filters a value.
+ * @param value the original unfiltered value.
+ * @return the filtered value.
+ */
+float LowpassFilter::filter(float value) {
+
+ float x1old = x1;
+ float x2old = x2;
+
+ x1 = a11*x1old+a12*x2old+b1*value;
+ x2 = a21*x1old+a22*x2old+b2*value;
+
+ return frequency*frequency*x1;
+}
+
diff -r 000000000000 -r bb408887ab78 LowpassFilter.h
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/LowpassFilter.h Fri Mar 09 15:29:36 2018 +0000
@@ -0,0 +1,39 @@
+/*
+ * LowpassFilter.h
+ * Copyright (c) 2018, ZHAW
+ * All rights reserved.
+ */
+
+#ifndef LOWPASS_FILTER_H_
+#define LOWPASS_FILTER_H_
+
+#include <cstdlib>
+
+/**
+ * This class implements a time-discrete 2nd order lowpass filter for a series of data values.
+ * This filter can typically be used within a periodic task that takes measurements that need
+ * to be filtered, like speed or position values.
+ */
+class LowpassFilter {
+
+ public:
+
+ LowpassFilter();
+ virtual ~LowpassFilter();
+ void reset();
+ void reset(float value);
+ void setPeriod(float period);
+ void setFrequency(float frequency);
+ float getFrequency();
+ float filter(float value);
+
+ private:
+
+ float period;
+ float frequency;
+ float a11, a12, a21, a22, b1, b2;
+ float x1, x2;
+};
+
+#endif /* LOWPASS_FILTER_H_ */
+
diff -r 000000000000 -r bb408887ab78 Motion.cpp
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/Motion.cpp Fri Mar 09 15:29:36 2018 +0000
@@ -0,0 +1,602 @@
+/*
+ * Motion.cpp
+ * Copyright (c) 2018, ZHAW
+ * All rights reserved.
+ */
+
+#include <cmath>
+#include <algorithm>
+#include "Motion.h"
+
+using namespace std;
+
+const float Motion::DEFAULT_LIMIT = 1.0f; // default value for limits
+const float Motion::MINIMUM_LIMIT = 1.0e-9f; // smallest value allowed for limits
+
+/**
+ * Creates a <code>Motion</code> object.
+ * The values for position, velocity and acceleration are set to 0.
+ */
+Motion::Motion() {
+
+ position = 0.0;
+ velocity = 0.0f;
+
+ profileVelocity = DEFAULT_LIMIT;
+ profileAcceleration = DEFAULT_LIMIT;
+ profileDeceleration = DEFAULT_LIMIT;
+}
+
+/**
+ * Creates a <code>Motion</code> object with given values for position and velocity.
+ * @param position the initial position value of this motion, given in [m] or [rad].
+ * @param velocity the initial velocity value of this motion, given in [m/s] or [rad/s].
+ */
+Motion::Motion(double position, float velocity) {
+
+ this->position = position;
+ this->velocity = velocity;
+
+ profileVelocity = DEFAULT_LIMIT;
+ profileAcceleration = DEFAULT_LIMIT;
+ profileDeceleration = DEFAULT_LIMIT;
+}
+
+/**
+ * Creates a <code>Motion</code> object with given values for position and velocity.
+ * @param motion another <code>Motion</code> object to copy the values from.
+ */
+Motion::Motion(const Motion& motion) {
+
+ position = motion.position;
+ velocity = motion.velocity;
+
+ profileVelocity = motion.profileVelocity;
+ profileAcceleration = motion.profileAcceleration;
+ profileDeceleration = motion.profileDeceleration;
+}
+
+/**
+ * Deletes the Motion object.
+ */
+Motion::~Motion() {}
+
+/**
+ * Sets the values for position and velocity.
+ * @param position the desired position value of this motion, given in [m] or [rad].
+ * @param velocity the desired velocity value of this motion, given in [m/s] or [rad/s].
+ */
+void Motion::set(double position, float velocity) {
+
+ this->position = position;
+ this->velocity = velocity;
+}
+
+/**
+ * Sets the values for position and velocity.
+ * @param motion another <code>Motion</code> object to copy the values from.
+ */
+void Motion::set(const Motion& motion) {
+
+ position = motion.position;
+ velocity = motion.velocity;
+}
+
+/**
+ * Sets the position value.
+ * @param position the desired position value of this motion, given in [m] or [rad].
+ */
+void Motion::setPosition(double position) {
+
+ this->position = position;
+}
+
+/**
+ * Gets the position value.
+ * @return the position value of this motion, given in [m] or [rad].
+ */
+double Motion::getPosition() {
+
+ return position;
+}
+
+/**
+ * Sets the velocity value.
+ * @param velocity the desired velocity value of this motion, given in [m/s] or [rad/s].
+ */
+void Motion::setVelocity(float velocity) {
+
+ this->velocity = velocity;
+}
+
+/**
+ * Gets the velocity value.
+ * @return the velocity value of this motion, given in [m/s] or [rad/s].
+ */
+float Motion::getVelocity() {
+
+ return velocity;
+}
+
+/**
+ * Sets the limit for the velocity value.
+ * @param profileVelocity the limit of the velocity.
+ */
+void Motion::setProfileVelocity(float profileVelocity) {
+
+ if (profileVelocity > MINIMUM_LIMIT) this->profileVelocity = profileVelocity; else this->profileVelocity = MINIMUM_LIMIT;
+}
+
+/**
+ * Sets the limit for the acceleration value.
+ * @param profileAcceleration the limit of the acceleration.
+ */
+void Motion::setProfileAcceleration(float profileAcceleration) {
+
+ if (profileAcceleration > MINIMUM_LIMIT) this->profileAcceleration = profileAcceleration; else this->profileAcceleration = MINIMUM_LIMIT;
+}
+
+/**
+ * Sets the limit for the deceleration value.
+ * @param profileDeceleration the limit of the deceleration.
+ */
+void Motion::setProfileDeceleration(float profileDeceleration) {
+
+ if (profileDeceleration > MINIMUM_LIMIT) this->profileDeceleration = profileDeceleration; else this->profileDeceleration = MINIMUM_LIMIT;
+}
+
+/**
+ * Sets the limits for velocity, acceleration and deceleration values.
+ * @param profileVelocity the limit of the velocity.
+ * @param profileAcceleration the limit of the acceleration.
+ * @param profileDeceleration the limit of the deceleration.
+ */
+void Motion::setLimits(float profileVelocity, float profileAcceleration, float profileDeceleration) {
+
+ if (profileVelocity > MINIMUM_LIMIT) this->profileVelocity = profileVelocity; else this->profileVelocity = MINIMUM_LIMIT;
+ if (profileAcceleration > MINIMUM_LIMIT) this->profileAcceleration = profileAcceleration; else this->profileAcceleration = MINIMUM_LIMIT;
+ if (profileDeceleration > MINIMUM_LIMIT) this->profileDeceleration = profileDeceleration; else this->profileDeceleration = MINIMUM_LIMIT;
+}
+
+/**
+ * Gets the time needed to move to a given target position.
+ * @param targetPosition the desired target position given in [m] or [rad].
+ * @return the time to move to the target position, given in [s].
+ */
+float Motion::getTimeToPosition(double targetPosition) {
+
+ // calculate position, when velocity is reduced to zero
+
+ double stopPosition = (velocity > 0.0f) ? position+(double)(velocity*velocity/profileDeceleration*0.5f) : position-(double)(velocity*velocity/profileDeceleration*0.5f);
+
+ if (targetPosition > stopPosition) { // positive velocity required
+
+ if (velocity > profileVelocity) { // slow down to profile velocity first
+
+ float t1 = (velocity-profileVelocity)/profileDeceleration;
+ float t2 = (float)(targetPosition-stopPosition)/profileVelocity;
+ float t3 = profileVelocity/profileDeceleration;
+
+ return t1+t2+t3;
+
+ } else if (velocity > 0.0f) { // speed up to profile velocity
+
+ float t1 = (profileVelocity-velocity)/profileAcceleration;
+ float t3 = profileVelocity/profileDeceleration;
+ float t2 = ((float)(targetPosition-position)-(velocity+profileVelocity)*0.5f*t1)/profileVelocity-0.5f*t3;
+
+ if (t2 < 0.0f) {
+ float maxVelocity = sqrt((2.0f*(float)(targetPosition-position)*profileAcceleration+velocity*velocity)*profileDeceleration/(profileAcceleration+profileDeceleration));
+ t1 = (maxVelocity-velocity)/profileAcceleration;
+ t2 = 0.0f;
+ t3 = maxVelocity/profileDeceleration;
+ }
+
+ return t1+t2+t3;
+
+ } else { // slow down to zero first, and then speed up to profile velocity
+
+ float t1 = -velocity/profileDeceleration;
+ float t2 = profileVelocity/profileAcceleration;
+ float t4 = profileVelocity/profileDeceleration;
+ float t3 = ((float)(targetPosition-position)-velocity*0.5f*t1)/profileVelocity-0.5f*(t2+t4);
+
+ if (t3 < 0.0f) {
+ float maxVelocity = sqrt((2.0f*(float)(targetPosition-position)*profileDeceleration+velocity*velocity)*profileAcceleration/(profileAcceleration+profileDeceleration));
+ t2 = maxVelocity/profileAcceleration;
+ t3 = 0.0f;
+ t4 = maxVelocity/profileDeceleration;
+ }
+
+ return t1+t2+t3+t4;
+ }
+
+ } else { // negative velocity required
+
+ if (velocity < -profileVelocity) { // slow down to (negative) profile velocity first
+
+ float t1 = (-profileVelocity-velocity)/profileDeceleration;
+ float t2 = (float)(stopPosition-targetPosition)/profileVelocity;
+ float t3 = profileVelocity/profileDeceleration;
+
+ return t1+t2+t3;
+
+ } else if (velocity < 0.0f) { // speed up to (negative) profile velocity
+
+ float t1 = (velocity+profileVelocity)/profileAcceleration;
+ float t3 = profileVelocity/profileDeceleration;
+ float t2 = ((float)(position-targetPosition)+(velocity-profileVelocity)*0.5f*t1)/profileVelocity-0.5f*t3;
+
+ if (t2 < 0.0f) {
+ float minVelocity = -sqrt((-2.0f*(float)(targetPosition-position)*profileAcceleration+velocity*velocity)*profileDeceleration/(profileAcceleration+profileDeceleration));
+ t1 = (velocity-minVelocity)/profileAcceleration;
+ t2 = 0.0f;
+ t3 = -minVelocity/profileDeceleration;
+ }
+
+ return t1+t2+t3;
+
+ } else { // slow down to zero first, and then speed up to (negative) profile velocity
+
+ float t1 = velocity/profileDeceleration;
+ float t2 = profileVelocity/profileAcceleration;
+ float t4 = profileVelocity/profileDeceleration;
+ float t3 = (-(float)(targetPosition-position)+velocity*0.5f*t1)/profileVelocity-0.5f*(t2+t4);
+
+ if (t3 < 0.0f) {
+ float minVelocity = -sqrt((-2.0f*(float)(targetPosition-position)*profileDeceleration+velocity*velocity)*profileAcceleration/(profileAcceleration+profileDeceleration));
+ t2 = -minVelocity/profileAcceleration;
+ t3 = 0.0f;
+ t4 = -minVelocity/profileDeceleration;
+ }
+
+ return t1+t2+t3+t4;
+ }
+ }
+}
+
+/**
+ * Increments the current motion towards a given target velocity.
+ * @param targetVelocity the desired target velocity given in [m/s] or [rad/s].
+ * @param period the time period to increment the motion values for, given in [s].
+ */
+void Motion::incrementToVelocity(float targetVelocity, float period) {
+
+ if (targetVelocity < -profileVelocity) targetVelocity = -profileVelocity;
+ else if (targetVelocity > profileVelocity) targetVelocity = profileVelocity;
+
+ if (targetVelocity > 0.0f) {
+
+ if (velocity > targetVelocity) { // slow down to target velocity
+
+ float t1 = (velocity-targetVelocity)/profileDeceleration;
+
+ if (t1 > period) {
+ position += (double)((velocity-profileDeceleration*0.5f*period)*period);
+ velocity += -profileDeceleration*period;
+ } else {
+ position += (double)((velocity-profileDeceleration*0.5f*t1)*t1);
+ velocity += -profileDeceleration*t1;
+ position += (double)(velocity*(period-t1));
+ }
+
+ } else if (velocity > 0.0f) { // speed up to target velocity
+
+ float t1 = (targetVelocity-velocity)/profileAcceleration;
+
+ if (t1 > period) {
+ position += (double)((velocity+profileAcceleration*0.5f*period)*period);
+ velocity += profileAcceleration*period;
+ } else {
+ position += (double)((velocity+profileAcceleration*0.5f*t1)*t1);
+ velocity += profileAcceleration*t1;
+ position += (double)(velocity*(period-t1));
+ }
+
+ } else { // slow down to zero first, and then speed up to target velocity
+
+ float t1 = -velocity/profileDeceleration;
+ float t2 = targetVelocity/profileAcceleration;
+
+ if (t1 > period) {
+ position += (double)((velocity+profileDeceleration*0.5f*period)*period);
+ velocity += profileDeceleration*period;
+ } else if (t1+t2 > period) {
+ position += (double)((velocity+profileDeceleration*0.5f*t1)*t1);
+ velocity += profileDeceleration*t1;
+ position += (double)((velocity+profileAcceleration*0.5f*(period-t1))*(period-t1));
+ velocity += profileAcceleration*(period-t1);
+ } else {
+ position += (double)((velocity+profileDeceleration*0.5f*t1)*t1);
+ velocity += profileDeceleration*t1;
+ position += (double)((velocity+profileAcceleration*0.5f*t2)*t2);
+ velocity += profileAcceleration*t2;
+ position += (double)(velocity*(period-t1-t2));
+ }
+ }
+
+ } else {
+
+ if (velocity < targetVelocity) { // slow down to (negative) target velocity
+
+ float t1 = (targetVelocity-velocity)/profileDeceleration;
+
+ if (t1 > period) {
+ position += (double)((velocity+profileDeceleration*0.5f*period)*period);
+ velocity += profileDeceleration*period;
+ } else {
+ position += (double)((velocity+profileDeceleration*0.5f*t1)*t1);
+ velocity += profileDeceleration*t1;
+ position += (double)(velocity*(period-t1));
+ }
+
+ } else if (velocity < 0.0f) { // speed up to (negative) target velocity
+
+ float t1 = (velocity-targetVelocity)/profileAcceleration;
+
+ if (t1 > period) {
+ position += (double)((velocity-profileAcceleration*0.5f*period)*period);
+ velocity += -profileAcceleration*period;
+ } else {
+ position += (double)((velocity-profileAcceleration*0.5f*t1)*t1);
+ velocity += -profileAcceleration*t1;
+ position += (double)(velocity*(period-t1));
+ }
+
+ } else { // slow down to zero first, and then speed up to (negative) target velocity
+
+ float t1 = velocity/profileDeceleration;
+ float t2 = -targetVelocity/profileAcceleration;
+
+ if (t1 > period) {
+ position += (double)((velocity-profileDeceleration*0.5f*period)*period);
+ velocity += -profileDeceleration*period;
+ } else if (t1+t2 > period) {
+ position += (double)((velocity-profileDeceleration*0.5f*t1)*t1);
+ velocity += -profileDeceleration*t1;
+ position += (double)((velocity-profileAcceleration*0.5f*(period-t1))*(period-t1));
+ velocity += -profileAcceleration*(period-t1);
+ } else {
+ position += (double)((velocity-profileDeceleration*0.5f*t1)*t1);
+ velocity += -profileDeceleration*t1;
+ position += (double)((velocity-profileAcceleration*0.5f*t2)*t2);
+ velocity += -profileAcceleration*t2;
+ position += (double)(velocity*(period-t1-t2));
+ }
+ }
+ }
+}
+
+/**
+ * Increments the current motion towards a given target position.
+ * @param targetPosition the desired target position given in [m] or [rad].
+ * @param period the time period to increment the motion values for, given in [s].
+ */
+void Motion::incrementToPosition(double targetPosition, float period) {
+
+ // calculate position, when velocity is reduced to zero
+
+ double stopPosition = (velocity > 0.0f) ? position+(double)(velocity*velocity/profileDeceleration*0.5f) : position-(double)(velocity*velocity/profileDeceleration*0.5f);
+
+ if (targetPosition > stopPosition) { // positive velocity required
+
+ if (velocity > profileVelocity) { // slow down to profile velocity first
+
+ float t1 = (velocity-profileVelocity)/profileDeceleration;
+ float t2 = (float)(targetPosition-stopPosition)/profileVelocity;
+ float t3 = profileVelocity/profileDeceleration;
+
+ if (t1 > period) {
+ position += (double)((velocity-profileDeceleration*0.5f*period)*period);
+ velocity += -profileDeceleration*period;
+ } else if (t1+t2 > period) {
+ position += (double)((velocity-profileDeceleration*0.5f*t1)*t1);
+ velocity += -profileDeceleration*t1;
+ position += (double)(velocity*(period-t1));
+ } else if (t1+t2+t3 > period) {
+ position += (double)((velocity-profileDeceleration*0.5f*t1)*t1);
+ velocity += -profileDeceleration*t1;
+ position += (double)(velocity*t2);
+ position += (double)((velocity-profileDeceleration*0.5f*(period-t1-t2))*(period-t1-t2));
+ velocity += -profileDeceleration*(period-t1-t2);
+ } else {
+ position += (double)((velocity-profileDeceleration*0.5f*t1)*t1);
+ velocity += -profileDeceleration*t1;
+ position += (double)(velocity*t2);
+ position += (double)((velocity-profileDeceleration*0.5f*t3)*t3);
+ velocity += -profileDeceleration*t3;
+ }
+
+ } else if (velocity > 0.0f) { // speed up to profile velocity
+
+ float t1 = (profileVelocity-velocity)/profileAcceleration;
+ float t3 = profileVelocity/profileDeceleration;
+ float t2 = ((float)(targetPosition-position)-(velocity+profileVelocity)*0.5f*t1)/profileVelocity-0.5f*t3;
+
+ if (t2 < 0.0f) {
+ float maxVelocity = sqrt((2.0f*(float)(targetPosition-position)*profileAcceleration+velocity*velocity)*profileDeceleration/(profileAcceleration+profileDeceleration));
+ t1 = (maxVelocity-velocity)/profileAcceleration;
+ t2 = 0.0f;
+ t3 = maxVelocity/profileDeceleration;
+ }
+
+ if (t1 > period) {
+ position += (double)((velocity+profileAcceleration*0.5f*period)*period);
+ velocity += profileAcceleration*period;
+ } else if (t1+t2 > period) {
+ position += (double)((velocity+profileAcceleration*0.5f*t1)*t1);
+ velocity += profileAcceleration*t1;
+ position += (double)(velocity*(period-t1));
+ } else if (t1+t2+t3 > period) {
+ position += (double)((velocity+profileAcceleration*0.5f*t1)*t1);
+ velocity += profileAcceleration*t1;
+ position += (double)(velocity*t2);
+ position += (double)((velocity-profileDeceleration*0.5f*(period-t1-t2))*(period-t1-t2));
+ velocity += -profileDeceleration*(period-t1-t2);
+ } else {
+ position += (double)((velocity+profileAcceleration*0.5f*t1)*t1);
+ velocity += profileAcceleration*t1;
+ position += (double)(velocity*t2);
+ position += (double)((velocity-profileDeceleration*0.5f*t3)*t3);
+ velocity += -profileDeceleration*t3;
+ }
+
+ } else { // slow down to zero first, and then speed up to profile velocity
+
+ float t1 = -velocity/profileDeceleration;
+ float t2 = profileVelocity/profileAcceleration;
+ float t4 = profileVelocity/profileDeceleration;
+ float t3 = ((float)(targetPosition-position)-velocity*0.5f*t1)/profileVelocity-0.5f*(t2+t4);
+
+ if (t3 < 0.0f) {
+ float maxVelocity = sqrt((2.0f*(float)(targetPosition-position)*profileDeceleration+velocity*velocity)*profileAcceleration/(profileAcceleration+profileDeceleration));
+ t2 = maxVelocity/profileAcceleration;
+ t3 = 0.0f;
+ t4 = maxVelocity/profileDeceleration;
+ }
+
+ if (t1 > period) {
+ position += (double)((velocity+profileDeceleration*0.5f*period)*period);
+ velocity += profileDeceleration*period;
+ } else if (t1+t2 > period) {
+ position += (double)((velocity+profileDeceleration*0.5f*t1)*t1);
+ velocity += profileDeceleration*t1;
+ position += (double)((velocity+profileAcceleration*0.5f*(period-t1))*(period-t1));
+ velocity += profileAcceleration*(period-t1);
+ } else if (t1+t2+t3 > period) {
+ position += (double)((velocity+profileDeceleration*0.5f*t1)*t1);
+ velocity += profileDeceleration*t1;
+ position += (double)((velocity+profileAcceleration*0.5f*t2)*t2);
+ velocity += profileAcceleration*t2;
+ position += (double)(velocity*(period-t1-t2));
+ } else if (t1+t2+t3+t4 > period) {
+ position += (double)((velocity+profileDeceleration*0.5f*t1)*t1);
+ velocity += profileDeceleration*t1;
+ position += (double)((velocity+profileAcceleration*0.5f*t2)*t2);
+ velocity += profileAcceleration*t2;
+ position += (double)(velocity*t3);
+ position += (double)((velocity-profileDeceleration*0.5f*(period-t1-t2-t3))*(period-t1-t2-t3));
+ velocity += -profileDeceleration*(period-t1-t2-t3);
+ } else {
+ position += (double)((velocity+profileDeceleration*0.5f*t1)*t1);
+ velocity += profileDeceleration*t1;
+ position += (double)((velocity+profileAcceleration*0.5f*t2)*t2);
+ velocity += profileAcceleration*t2;
+ position += (double)(velocity*t3);
+ position += (double)((velocity-profileDeceleration*0.5f*t4)*t4);
+ velocity += -profileDeceleration*t4;
+ }
+ }
+
+ } else { // negative velocity required
+
+ if (velocity < -profileVelocity) { // slow down to (negative) profile velocity first
+
+ float t1 = (-profileVelocity-velocity)/profileDeceleration;
+ float t2 = (float)(stopPosition-targetPosition)/profileVelocity;
+ float t3 = profileVelocity/profileDeceleration;
+
+ if (t1 > period) {
+ position += (double)((velocity+profileDeceleration*0.5f*period)*period);
+ velocity += profileDeceleration*period;
+ } else if (t1+t2 > period) {
+ position += (double)((velocity+profileDeceleration*0.5f*t1)*t1);
+ velocity += profileDeceleration*t1;
+ position += (double)(velocity*(period-t1));
+ } else if (t1+t2+t3 > period) {
+ position += (double)((velocity+profileDeceleration*0.5f*t1)*t1);
+ velocity += profileDeceleration*t1;
+ position += (double)(velocity*t2);
+ position += (double)((velocity+profileDeceleration*0.5f*(period-t1-t2))*(period-t1-t2));
+ velocity += profileDeceleration*(period-t1-t2);
+ } else {
+ position += (double)((velocity+profileDeceleration*0.5f*t1)*t1);
+ velocity += profileDeceleration*t1;
+ position += (double)(velocity*t2);
+ position += (double)((velocity+profileDeceleration*0.5f*t3)*t3);
+ velocity += profileDeceleration*t3;
+ }
+
+ } else if (velocity < 0.0f) { // speed up to (negative) profile velocity
+
+ float t1 = (velocity+profileVelocity)/profileAcceleration;
+ float t3 = profileVelocity/profileDeceleration;
+ float t2 = ((float)(position-targetPosition)+(velocity-profileVelocity)*0.5f*t1)/profileVelocity-0.5f*t3;
+
+ if (t2 < 0.0f) {
+ float minVelocity = -sqrt((-2.0f*(float)(targetPosition-position)*profileAcceleration+velocity*velocity)*profileDeceleration/(profileAcceleration+profileDeceleration));
+ t1 = (velocity-minVelocity)/profileAcceleration;
+ t2 = 0.0f;
+ t3 = -minVelocity/profileDeceleration;
+ }
+
+ if (t1 > period) {
+ position += (double)((velocity-profileAcceleration*0.5f*period)*period);
+ velocity += -profileAcceleration*period;
+ } else if (t1+t2 > period) {
+ position += (double)((velocity-profileAcceleration*0.5f*t1)*t1);
+ velocity += -profileAcceleration*t1;
+ position += (double)(velocity*(period-t1));
+ } else if (t1+t2+t3 > period) {
+ position += (double)((velocity-profileAcceleration*0.5f*t1)*t1);
+ velocity += -profileAcceleration*t1;
+ position += (double)(velocity*t2);
+ position += (double)((velocity+profileDeceleration*0.5f*(period-t1-t2))*(period-t1-t2));
+ velocity += profileDeceleration*(period-t1-t2);
+ } else {
+ position += (double)((velocity-profileAcceleration*0.5f*t1)*t1);
+ velocity += -profileAcceleration*t1;
+ position += (double)(velocity*t2);
+ position += (double)((velocity+profileDeceleration*0.5f*t3)*t3);
+ velocity += profileDeceleration*t3;
+ }
+
+ } else { // slow down to zero first, and then speed up to (negative) profile velocity
+
+ float t1 = velocity/profileDeceleration;
+ float t2 = profileVelocity/profileAcceleration;
+ float t4 = profileVelocity/profileDeceleration;
+ float t3 = (-(float)(targetPosition-position)+velocity*0.5f*t1)/profileVelocity-0.5f*(t2+t4);
+
+ if (t3 < 0.0f) {
+ float minVelocity = -sqrt((-2.0f*(float)(targetPosition-position)*profileDeceleration+velocity*velocity)*profileAcceleration/(profileAcceleration+profileDeceleration));
+ t2 = -minVelocity/profileAcceleration;
+ t3 = 0.0f;
+ t4 = -minVelocity/profileDeceleration;
+ }
+
+ if (t1 > period) {
+ position += (double)((velocity-profileDeceleration*0.5f*period)*period);
+ velocity += -profileDeceleration*period;
+ } else if (t1+t2 > period) {
+ position += (double)((velocity-profileDeceleration*0.5f*t1)*t1);
+ velocity += -profileDeceleration*t1;
+ position += (double)((velocity-profileAcceleration*0.5f*(period-t1))*(period-t1));
+ velocity += -profileAcceleration*(period-t1);
+ } else if (t1+t2+t3 > period) {
+ position += (double)((velocity-profileDeceleration*0.5f*t1)*t1);
+ velocity += -profileDeceleration*t1;
+ position += (double)((velocity-profileAcceleration*0.5f*t2)*t2);
+ velocity += -profileAcceleration*t2;
+ position += (double)(velocity*(period-t1-t2));
+ } else if (t1+t2+t3+t4 > period) {
+ position += (double)((velocity-profileDeceleration*0.5f*t1)*t1);
+ velocity += -profileDeceleration*t1;
+ position += (double)((velocity-profileAcceleration*0.5f*t2)*t2);
+ velocity += -profileAcceleration*t2;
+ position += (double)(velocity*t3);
+ position += (double)((velocity+profileDeceleration*0.5f*(period-t1-t2-t3))*(period-t1-t2-t3));
+ velocity += profileDeceleration*(period-t1-t2-t3);
+ } else {
+ position += (double)((velocity-profileDeceleration*0.5f*t1)*t1);
+ velocity += -profileDeceleration*t1;
+ position += (double)((velocity-profileAcceleration*0.5f*t2)*t2);
+ velocity += -profileAcceleration*t2;
+ position += (double)(velocity*t3);
+ position += (double)((velocity+profileDeceleration*0.5f*t4)*t4);
+ velocity += profileDeceleration*t4;
+ }
+ }
+ }
+}
+
diff -r 000000000000 -r bb408887ab78 Motion.h
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/Motion.h Fri Mar 09 15:29:36 2018 +0000
@@ -0,0 +1,60 @@
+/*
+ * Motion.h
+ * Copyright (c) 2018, ZHAW
+ * All rights reserved.
+ */
+
+#ifndef MOTION_H_
+#define MOTION_H_
+
+#include <cstdlib>
+
+/**
+ * This class keeps the motion values <code>position</code> and <code>velocity</code>, and
+ * offers methods to increment these values towards a desired target position or velocity.
+ * <br/>
+ * To increment the current motion values, this class uses a simple 2nd order motion planner.
+ * This planner calculates the motion to the target position or velocity with the various motion
+ * phases, based on given limits for the profile velocity, acceleration and deceleration.
+ * <br/>
+ * Note that the trajectory is calculated every time the motion state is incremented.
+ * This allows to change the target position or velocity, as well as the limits for profile
+ * velocity, acceleration and deceleration at any time.
+ */
+class Motion {
+
+ public:
+
+ double position; /**< The position value of this motion, given in [m] or [rad]. */
+ float velocity; /**< The velocity value of this motion, given in [m/s] or [rad/s]. */
+
+ Motion();
+ Motion(double position, float velocity);
+ Motion(const Motion& motion);
+ virtual ~Motion();
+ void set(double position, float velocity);
+ void set(const Motion& motion);
+ void setPosition(double position);
+ double getPosition();
+ void setVelocity(float velocity);
+ float getVelocity();
+ void setProfileVelocity(float profileVelocity);
+ void setProfileAcceleration(float profileAcceleration);
+ void setProfileDeceleration(float profileDeceleration);
+ void setLimits(float profileVelocity, float profileAcceleration, float profileDeceleration);
+ float getTimeToPosition(double targetPosition);
+ void incrementToVelocity(float targetVelocity, float period);
+ void incrementToPosition(double targetPosition, float period);
+
+ private:
+
+ static const float DEFAULT_LIMIT; // default value for limits
+ static const float MINIMUM_LIMIT; // smallest value allowed for limits
+
+ float profileVelocity;
+ float profileAcceleration;
+ float profileDeceleration;
+};
+
+#endif /* MOTION_H_ */
+