Questions about first time trying 6WD.

[Ben Piecuch]

Originally Posted by NHPilot

Question: If the center wheels are lower such that only four wheels touch at any given time, what would be the advantage of six wheels? I suppose it could be more manueverable for the short time it is teetering on the center wheels when weight transfers from front to rear for instance.

The fact that only 4 wheels are touching is what makes 6wd so advantageous. A typical 4wd setup has 4 wheels at the farthest corners of the robot, and therefore requires the largest amount of force/torque to turn the robot. If you were to shorten the front-back wheelbase with only these 4 wheels, the robot is now easier to turn. However, it can become very unstable in full forward to full reverse (and similar) maneuvers, or when using long and/or tall arms.

6wd effectively shortens the wheelbase to 1/2 the length of the robot, due to the fact that it only rides on 4 wheels at a time. However, it regains the stability of the long wheelbase robot because of the extra 2 wheels at the other end of the bot. Add to the fact that all 6 wheels are powered, and you have a drivetrain that optimizes a long and short wheelbase robot.

Pushing power between a 6wd and a 4wd should be no different, as only 4 wheels are on the ground at a time for both robots. (also assuming the same motors, gearing, wheels, etc...) We used 6wd for the 1st time last year, and it served us extremely wheel. YMMV. Best of luck.

BEN