Hi,
I'm trying to build a GPS navigation car that follows a whole set of wave points entered by the user.
The only problem is that the robot will make unnecessary movements between wave points.
Since I cannot afford to buy a centimeter accurate GPS module, I was thinking about using an accelerometer sensor, but they only measure tilt.
Any suggestions?
Use an IMU that will give you a North reference, so you can maintain a more or less constant heading between waypoints. One commercial option is the CHRobotics UM7, or you can make your own much more cheaply with an IMU such as the LSM303DLHC, an Arduino Pro Mini, and the RTIMUlib software package.
For an example of the latter, see this post http://forum.pololu.com/viewtopic.php?f=32&t=9833
why would an accelerometer help to keep the car on track? Does the IMU measure the Euler angles and keep the car on track?
An IMU has an accelerometer and a gyro, and often a magnetometer to give orientation and heading relative to North.