The Program derives motor bots getting instructions(speed, turn, stop,etc) from accelerometer.

Dependencies:   Motordriver mbed

Files at this revision

API Documentation at this revision

Comitter:
samgang
Date:
Sun Oct 27 16:42:08 2013 +0000
Commit message:
Initial Commit

Changed in this revision

Motordriver.lib Show annotated file Show diff for this revision Revisions of this file
main.cpp Show annotated file Show diff for this revision Revisions of this file
mbed.bld Show annotated file Show diff for this revision Revisions of this file
diff -r 000000000000 -r c5c22fd71be8 Motordriver.lib
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/Motordriver.lib	Sun Oct 27 16:42:08 2013 +0000
@@ -0,0 +1,1 @@
+http://mbed.org/users/littlexc/code/Motordriver/#3110b9209d3c
diff -r 000000000000 -r c5c22fd71be8 main.cpp
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/main.cpp	Sun Oct 27 16:42:08 2013 +0000
@@ -0,0 +1,61 @@
+/* This program uses Christopher Hasler motor library to derive DC motors */
+
+#include "mbed.h"
+#include "motordriver.h"
+
+// Array of Motor type objects to define 4 motors for two bots.
+Motor M[]= {Motor(p25, p9, p8, 1), Motor(p26, p11, p10, 1), Motor(p21, p13, p12, 1), Motor(p22, p15, p14, 1)};
+// Array acc defines 4 analogin type objects to detect inputs of accelerometer.
+AnalogIn acc[]= {p16, p17, p19, p18};
+/*@update reads recent values from accelerometer and uses them to control motors
+  @param 'a' tell for which bot the vales should be updated( a=0 for 1st bot and a=2 for 2nd bot)
+*/
+int update(int a)
+{
+    float offx=0, offy=0, map=0, turnp=0, turnn=0;
+    /*output votage of accelerometer at x and y outs when x=0 and y=0;
+      turnp and turnn specifies the positive and negative voltage difference(CurrentVoltage - offset) detected from offset value when accelerometer is tilted.
+      I will be using turnp and turnn as the minimum required voltage difference(ie, the minimum required tilt) to turn the bot.
+      The value below are default ones for my accelerometer
+    */
+    if(a==0) {
+        offx=0.340;
+        offy=0.340;
+        turnp=0.032;
+        turnn=0.055;
+        map=14.68;
+    } else if(a==2) {
+        offx=0.350;
+        offy=0.440;
+        turnp=0.040;
+        turnn=0.045;
+        map=13.40;
+    } else
+        return(-1);  // return -1 as error when update is called with unexpected argument value
+    float s=0, st=0; 
+    s=acc[a+1].read();
+    s=(s-offy)*map; // multiply by 'map' to linearly map difference (s-offy) to euivalent scale on 0 to 1 so that s can be used as speed
+                    // (s=0 for (s-offy)=0 and s=1 for max[(s-offy)] )
+    st=acc[a].read();
+    st=st-offx;
+    if(st>0 && abs(st)>turnp) {  // checking whether to turn or not ( st>0: right turn and st<0: left trun)
+        M[a].speed(0);
+        M[a+1].speed(1);
+    } else if(st<0 && abs(st)>turnn) {
+        M[a].speed(1);
+        M[a+1].speed(0);
+    } else {    // if no turn input then run both motors with speed s
+        M[a].speed(s);
+        M[a+1].speed(s);
+    }
+    return 1;
+}
+
+int main()
+{
+    while(1) {
+        update(0);  // Calling update for first bot(a=0) and second bot(a=2)
+        update(2);
+        wait(0.2);
+    }
+}
\ No newline at end of file
diff -r 000000000000 -r c5c22fd71be8 mbed.bld
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/mbed.bld	Sun Oct 27 16:42:08 2013 +0000
@@ -0,0 +1,1 @@
+http://mbed.org/users/mbed_official/code/mbed/builds/a9913a65894f
\ No newline at end of file