The steering mechanism is a simple column and lever arm arrangement and to keep the design as simple as possible I've used symmetrical connecting rods to join each front wheel to the lever arm. The front wheels pivot about vertical king pins, a support arrangement that should be simple to make and robust in use. Lock to lock the front wheels will move over +/- 40 degree range giving the machine a good level of manoeuvrability. This will be assisted by the differential behaviour of the independent drive to each rear wheel.
The wheels are inexpensive 10" pneumatics with steel rims.
The main vehicle chassis is a simple to build glued and screwed timber construction. Ground clearance is fairly limited at roughly 50 mm (2") - so the design is intended primarily for running on good drive surfaces and not for off-road use. Should be okay on smooth (mown) grass surfaces.
In use the kart will need to be fitted with a strong karting style bucket seat to ensure the driver is supported properly and the seat would be securely fixed to the main chassis longerons. Seat belt attachments will also need to be fixed securely to the main structural elements of the chassis towards the rear of the seat.
A 36V reversing controller will suit the design. The combined rated current draw of the two 750W motors will be around 50 Amps, this will peak at over 100 Amps during hard acceleration so a 100+ Amp 36V controller is probably required. Assuming an average current draw of roughly half the rated current of the motors the 3 x 12V 40 AmpH batteries should give roughly 1.5 hours continuous use between charges (load and driving style dependent).
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