Open-Source Sports Electric Vehicle (OSSEV®)
The steering wheel is the second most important sensory interface with the driver in any sports car (after the seat) and is also the primary control interface for the driver. In a super-light car like Rob's Fisher Fury R1 you can get away without power assistance and in a the sub-1000kg OSSEV® we also don't think we are going to need it.
To test our theory out, we have removed the power steering from our MX-5e and modified the rack to minimise resistance. This will give a much more diurect connection to the front wheels.
The initial plan is to have a simple steering wheel with a central integrated horn button, some control buttons and no air bag.
In the MX-5e we have hand-stitched a leather cover to a 360mm Momo wheel and purchased a new boss to mount it.
We have 3D printed button mounting plates to test out the usability of the planned steering wheel buttons.
All of the buttons in the OSSEV® will be physical and tactile, with a positive action. There will be no touch sensitive controls, other than the entertainment screen.
The buttons on the steering wheel can be split into two sections:
The steering column will be both height and reach adjustable, to ensure the optimal driving position.
The steering rack will be fairly quick, to enable better control on the limits of handling.
With the MX-5e we sticking with the standard power steering rack (because it has a faster ratio than a manual one) but, we are removing the power assistance and modifying the steering rack to reduce the internal resistance. This should provide a nice feel and weight, though it may feel a bit heavy at slow speeds to some.
On the MX-5e, we are using Superpro polyurethane power steering rack bushes to improve the stiffness of the rack mounting and to maximise feel through the steering wheel.
Whilst some cars feature a heated steering wheel but, this is not something planned for the OSSEV®.