Servo control routines

Dependents:   Q2_Stabi

Files at this revision

API Documentation at this revision

Comitter:
Decimus
Date:
Mon May 30 08:09:19 2016 +0000
Commit message:
[+]

Changed in this revision

Servo.cpp Show annotated file Show diff for this revision Revisions of this file
Servo.h Show annotated file Show diff for this revision Revisions of this file
diff -r 000000000000 -r b3bed6121155 Servo.cpp
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/Servo.cpp	Mon May 30 08:09:19 2016 +0000
@@ -0,0 +1,75 @@
+/* mbed R/C Servo Library
+ *  
+ * Copyright (c) 2007-2010 sford, cstyles
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+ 
+#include "Servo.h"
+#include "mbed.h"
+
+static float clamp(float value, float min, float max) {
+    if(value < min) {
+        return min;
+    } else if(value > max) {
+        return max;
+    } else {
+        return value;
+    }
+}
+
+Servo::Servo(PinName pin) : _pwm(pin) {
+    //calibrate();
+    //write(0.5);
+}
+
+void Servo::write(float percent) {
+    float offset = _range * 2.0 * (percent - 0.5);
+    _pwm.pulsewidth(0.0015 + clamp(offset, -_range, _range));
+    _p = clamp(percent, 0.0, 1.0);
+}
+
+void Servo::position(float degrees) {
+    float offset = _range * (degrees / _degrees);
+    _pwm.pulsewidth(0.0015 + clamp(offset, -_range, _range));
+}
+
+void Servo::calibrate(float range, float degrees, float period) {
+    _range = range;
+    _degrees = degrees;
+    _pwm.period(period);
+}
+
+float Servo::read() {
+    return _p;
+}
+
+Servo& Servo::operator= (float percent) { 
+    write(percent);
+    return *this;
+}
+
+Servo& Servo::operator= (Servo& rhs) {
+    write(rhs.read());
+    return *this;
+}
+
+Servo::operator float() {
+    return read();
+}
diff -r 000000000000 -r b3bed6121155 Servo.h
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/Servo.h	Mon May 30 08:09:19 2016 +0000
@@ -0,0 +1,98 @@
+/* mbed R/C Servo Library
+ * Copyright (c) 2007-2010 sford, cstyles
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+  
+#ifndef MBED_SERVO_H
+#define MBED_SERVO_H
+
+#include "mbed.h"
+
+/** Servo control class, based on a PwmOut
+ *
+ * Example:
+ * @code
+ * // Continuously sweep the servo through it's full range
+ * #include "mbed.h"
+ * #include "Servo.h"
+ * 
+ * Servo myservo(p21);
+ * 
+ * int main() {
+ *     while(1) {
+ *         for(int i=0; i<100; i++) {
+ *             myservo = i/100.0;
+ *             wait(0.01);
+ *         }
+ *         for(int i=100; i>0; i--) {
+ *             myservo = i/100.0;
+ *             wait(0.01);
+ *         }
+ *     }
+ * }
+ * @endcode
+ */
+class Servo {
+
+public:
+    /** Create a servo object connected to the specified PwmOut pin
+     *
+     * @param pin PwmOut pin to connect to 
+     */
+    Servo(PinName pin);
+    
+    /** Set the servo position, normalised to it's full range
+     *
+     * @param percent A normalised number 0.0-1.0 to represent the full range.
+     */
+    void write(float percent);
+    
+    /**  Read the servo motors current position
+     *
+     * @param returns A normalised number 0.0-1.0  representing the full range.
+     */
+    float read();
+    
+    /** Set the servo position
+     *
+     * @param degrees Servo position in degrees
+     */
+    void position(float degrees);
+    
+    /**  Allows calibration of the range and angles for a particular servo
+     *
+     * @param range Pulsewidth range from center (1.5ms) to maximum/minimum position in seconds
+     * @param degrees Angle from centre to maximum/minimum position in degrees
+     */
+    void calibrate(float range = 0.0005, float degrees = 45.0, float period = 0.020); 
+        
+    /**  Shorthand for the write and read functions */
+    Servo& operator= (float percent);
+    Servo& operator= (Servo& rhs);
+    operator float();
+
+protected:
+    PwmOut _pwm;
+    float _range;
+    float _degrees;
+    float _p;
+};
+
+#endif