Robot Base from Hobby King

 

L293D power drive chip 

 

Here is the link to a good lm293 guide

http://m.instructables.com/id/Control-your-motors-with-L293D-and-Arduino/step3/Arduino-code/ 

with a larger blow up of the L293D on a prototype board

Shipping for HC05 Modules  EBAY tracking

http://vod.ebay.com/vod/FetchOrderDetails?ViewPaymentStatus&transId=1224051213018&itemid=281348747108

Shipping for Arduinos  ada fruit order    530186-5768100666

Here is a simple front/back, left right robot control on instructable 

http://www.instructables.com/id/Control-DC-Motors-with-your-Smartphone-Perfect-for/

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I the site we used to wire the motors is

Instructables

http://m.instructables.com/id/Control-DC-Motors-with-your-Smartphone-Perfect-for/

The simplest android phone software is at tech bitar.

He has a very simple interface that toggles any pin on the arduino high and low.

http://www.techbitar.com/ardudroid-simple-bluetooth-control-for-arduino-and-android.html

John David was able to get his bot rolling using that combination.

The final puzzle piece is MIT App Inventor.  That would facilitate a real controller interface on the phone.

I would love to do a Saturday follow-up this fall.

By the way.  The motors are wired in series to slow the robot down.  I think that was a mistake.  I think they should be wired parallel to allow full battery voltage to drive each motor.

Jenny is setting up a saturday, so if you are interested please get in touch with her.

Good luck and keep in touch

nice write up of a HS robotics class

http://makezine.com/2015/01/05/losing-to-my-high-school-class-a-big-win/