![](/media/cache/profiles/4dfa8c1c082dc012ffd94c2baa621a41.jpg.50x50_q85.jpg)
With Stretch Senser and Accelerometer
Dependencies: ADXL345 USBDevice mbed
Fork of Slingshot by
main.cpp
- Committer:
- SRINATHMADHU
- Date:
- 2015-10-15
- Revision:
- 1:5a2ea4e2e236
- Parent:
- 0:6fef570fcbc4
File content as of revision 1:5a2ea4e2e236:
/* mbed USB Slingshot, * * Copyright (c) 2010-2011 mbed.org, MIT License * * smokrani, sford * * 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 "mbed.h" #include "USBMouse.h" #include "ADXL345.h" // Physical interfaces USBMouse mouse; ADXL345 accelerometer(p5, p6, p7, p8); AnalogIn stretch_sensor(p15); BusOut leds(LED1, LED2, LED3, LED4); // Return slingshot angle in radians, up > 0 > down float get_angle() { int readings[3]; accelerometer.getOutput(readings); float x = (int16_t)readings[0]; float z = (int16_t)readings[2]; return atan(z / x); } // Return normalised stretch value based on bounds of all readings seen float get_stretch() { static float min_strength = 0.7; static float max_strength = 0.7; float current_strength = stretch_sensor.read(); if(current_strength > max_strength) { max_strength = current_strength; } if(current_strength < min_strength) { min_strength = current_strength; } float stretch = (current_strength - min_strength) / (max_strength - min_strength); return 1.0 - stretch; } // move mouse to a location relative to the start point, stepping as needed void move_mouse(int x, int y) { const int STEP = 10; static int current_x = 0; static int current_y = 0; int move_x = x - current_x; int move_y = y - current_y; // Move the mouse, in steps of max step size to ensure it is picked up by OS while(move_x > STEP) { mouse.move(STEP, 0); move_x -= STEP; } while(move_x < -STEP) { mouse.move(-STEP, 0); move_x += STEP; } while(move_y > STEP) { mouse.move(0, STEP); move_y -= STEP; } while(move_y < -STEP) { mouse.move(0, -STEP); move_y += STEP; } mouse.move(move_x, move_y); current_x = x; current_y = y; } template <class T> T filter(T* array, int len, T value) { T mean = 0.0; for(int i = 0; i<len - 1; i++) { mean += array[i + 1]; array[i] = array[i + 1]; } mean += value; array[len - 1] = value; return mean / (T)len; } typedef enum { WAITING = 2, AIMING = 4, FIRING = 8 } state_t; int main() { leds = 1; // setup accelerometer accelerometer.setPowerControl(0x00); accelerometer.setDataFormatControl(0x0B); accelerometer.setDataRate(ADXL345_3200HZ); accelerometer.setPowerControl(0x08); state_t state = WAITING; Timer timer; float angles[8] = {0}; float stretches[8] = {0}; while(1) { // get the slingshot parameters float this_stretch = get_stretch(); float this_angle = get_angle(); // apply some filtering float stretch = filter(stretches, 8, this_stretch); float angle = filter(angles, 8, this_angle); leds = state; // act based on the current state switch (state) { case WAITING: if(stretch > 0.5) { // significant stretch, considered starting mouse.press(MOUSE_LEFT); state = AIMING; } break; case AIMING: if(stretch - this_stretch > 0.1) { // rapid de-stretch, considered a fire mouse.release(MOUSE_LEFT); move_mouse(0, 0); timer.start(); state = FIRING; } else { int x = 0.0 - cos(angle) * stretch * 200; int y = sin(angle) * stretch * 200; move_mouse(x, y); } break; case FIRING: if(timer > 3.0) { timer.stop(); timer.reset(); state = WAITING; } break; }; wait(0.01); } }