Steerable Dune Buggy

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Here is an attempt to create a steerable dune buggy out of K'nex pieces. Unlike the custom pieces often found in Lego sets, K'nex parts are generic and require a bit more creative thinking in order to formulate workable mechanical designs. Early on, we noticed that all of the many vehicle designs in the K'nex instruction books showed wheels in a fixed orientation, capable of moving only in a straight line. The simplest approach to making a vehicle steerable would be to attach the midpoint of a rigid front axle to a vertical pivot rod that passes through a horizontal hole in the front of the car body. The top of the pivot rod could then be firmly attached at right angles to a control rod passing back to the cab area of the vehicle. While simple, this construction lacks realism since the front wheels do not turn with respect to their axle and the control mechanism is not in the form of a steering wheel. Instead, we looked at ways we could create a flexible parallelogram out of K'nex pieces - the front wheels could then attach via kingpins to one pair of corners and the other pair of corners would be used as part of the steering control apparatus. The design we finally ended up with uses quite a few parts in order to establish rigidity where it's needed. It includes a hook attached to a horizontal steering column to move vertical posts fixed to the rear edge of the front axle parallelogram.