BrickVista - M.O.P Rover

Steering Method
As we have seen both Exclusive and Differential Drive Assembly configurations provide a single output axle to both sides of the chassis enabling ‘Skid' steering. When turning, one side of the vehicle ‘skids’ while the other moves.

The M.O.P relies on 'Skid' steering to steer and change orientation. Typically two primary wheels are used for steering, (The Discovery configuration uses four). When turning both wheels are counter rotated resulting in a very small turning circle (the width of the M.O.P)

By using wheels instead of tracks we reduce ground resistance by having a smaller contact area with the ground (this is an acceptable trade off between resistance, traction and performance). Two ancillary casters (front and rear) are used for stability. The Casters are not powered and can pivot through 360°.

The central location of the drive wheels means the M.O.P has a 0° turning circle. Caster movement is also contained within the overall operational footprint.

The standard M.O.P chassis has a 0° turning circle. Both casters provide stability when steering and are able to pivot freely through 360°.

Skid Steering by nature is a very simple steering method. A typical steering sequence is:

Movment Stopped Forward/Reverse movement stopped.

Movment Stopped Wheels on each side of the rover turn in opposite directions The longer the wheels are left to turn the more the Rover pivots. A short duration results in a small change of direction. A long duration will see the Rover pivot through 360°.

Movment Stopped Forward/Reverse movement commences.

CATERPILLAR

Original Caterpillar

The Original ‘Caterpillar’ Tractor - designed in 1906 by Benjamin Holt, was steam powered and the first successful track-type tractor which used the ‘skid’ steering method.

BOBCAT

The Bobcat is a common skid steering vehicles used today in the construction industry.

Check out Jennifer Clark's amazing models and fully working BobCat here.

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