Saturday, July 20, 2013

Robot out for a spin for the first time

Sunday, July 7, 2013

Robot Building

Finally all the pieces are in place and I took the robot for a wireless ride around the house. The original VSI controller have been officially hacked.  The robot still retains all the functionality of the original VSI and also can be switch to Radio Control at the drop of a hat!
I needed to build a low pass filter for the PWM output from the arduino  and it worked out pretty well.
The fillers smooth out the PWM pulses as explained in this article

There is a noticeable delay when I move the stick on the RC transmitter, kinda  frightening when the see the robot takes off and does not respond to the stop command immediately!
I will play around with different values of resistors and capacitors in the coming weeks to increase the responsiveness.

I also had to re-write the code for the arduino that I posted some time ago, pretty simple indeed but It will get very much more complex when I  add bump, and ultrasonic sensors. These will be autonomic sensors to prevent the robot from bumping into things and falling off edges. etc. Ideally a visual sensor system  would be the navigation system of choice to prevent bumping  into thing and falling off steps and overhangs.

Next  on the list of  things to be done
1. I will tidy thing up a bit by using a arduino shield for the filters and a project box to host all the electronics.
2. Add support to the code for the horn and speed selector ( why do I need the horn working?)
3. Add bump sensors and supporting code
3. Add ultrasonic sensors and supporting code