Custom-Molded Steering Wheels Improve the Feedback's Signal-to-Noise Ratio
Ed Dellis, The Steering Wheel Guy, explains how the human brain initially associates increased grip tension with more control...which is BACKWARDS when you're trying to feel the steering wheel feedback so you can drive closer to the limit with more confidence.
He uses pails of water and a stone to demonstrate how the muscles in your forearms need to be operating in their sweetspot in order to be able to sense steering wheel resistance which is directly proportional to the amount of traction under the front tires at any given time in a corner.
The graph displayed shows the ideal force sweetspot at the top, and how two forces at the bottom consume nerve motor innervation to supply both the work out of the wheel, and controlling the wheel itself.
With a standard steering wheel, friction is the primary control mode and this consumes extra effort since the forces acting on the wheel to control it are 90-degrees from the opposing force (steering resistance in rotation)...NOT SO when you have a custom-molded steering wheel that's molded PROPERLY.
The force remaining (in blue at the top ) is what's left over for sensing steering wheel resistance, and therefore sensing the traction available. This demonstrates how you get an improved SIGNAL-TO-NOISE RATIO when using a properly molded steering wheel.
Dellis closes with a description of how blisters are formed on your hands when using a regular racing steering wheel made of leather, suede, plastic, or rubber that relies on the friction between your hand, glove, and the steering wheel.