Purpose:   To construct a small lego car that can be controlled, both steering and speed, by an accelerometer.  A standard servo will be used to control the steering and a stepper motor for forward/reverse direction and speed control. Required Parts: 1- Accelerometer  1- Atmel 89c55WD Microprocessor  Portable 5V and 7V power supplies  1- 5V Servo to control steering  1- 7V Stepper Motor for speed Lots of Legos Steps: Building the Car Adjusting/Using Accelerometer Controlling the Servo Controlling/Using Stepper Motor  Problems Faced: Current draw from Components Limitations of Stepper Motors

Summary:

Overall the project was a great learning experience.  We faced challenges that we didn't anticipate and had to adapt to turn the car into a semi-working success.  The Stepper Motor turned out to be a poor choice for a motor to drive the car.  It didn't have enough torque, even with normal operating conditions, to push the car any faster than a baby's crawl.  Controlling the servo didn't turn out to be a big challenge, but it was a bit 'jittery' with the fluctuating input from the accelerometer.   We added some averaging to smooth this problem.  

Conclusions:

- Do not use a Stepper Motor to power a car.
- Make sure to double check the current draw from components
- Legos fall apart easily