DEWBOT II Drive Train

Drive detail

DEWBOT II possessed a 2-wheel drive (2wd) / rear-wheel drive Drive-train. This drive-train was generally satisfactory. The robot's concentration of mass aft (where the drives and ball lift live) kept the rear wheels weighted and thereby avoided DEWBOT IV's steering difficulties.

The drive-train was reliable. I recall no drive-train failures.

The drive-train made it almost impossible to get up the ramp at the match end to score bonus points. We only succeeded once. Running up forwards would land DEWBOT II on its back due to high & aft center-of mass. Running up backwards unweighted the rear wheels, depriving us of the needed traction. Only way to succeed was to run up backwards with a running start and allow momentum to carry us up; something of a semi-controlled crash. Not for the timid.

One CIM motor per side. Tank drive with Arcade control. KOP gearbox used with type 35 steel chain between drive and wheel sprockets. Encoders were installed on each of the drive wheel axles. Chain guards were installed for safety.

Undriven front wheels were originally swivels, but were changed to onmi wheels during the build season due to unsatisfactory performance of the swivels.

The standard KitBot frame was used, with the front U-channel replaced with a custom element to allow ball pick-up.

Drivetrain Strengths:

• driving / steering quite good
• mechanically simple - simple to control - easy design to execute

Drivetrain Weaknesses:

• DEWBOT II was easily pushed off target
• it was very difficult to get up the ramp to score bonus points (only succeeded once)
• Center-of-Mass relatively high and off-center (aft)