Artillery wheel Artillery wheel The artillery wheel was developed for use on gun carriages when it was found that the lateral forces involved in horse artillery manoeuvres caused normally constructed cart wheels to collapse. Rather than having its spokes mortised into a wooden nave (hub), it has them fitted together (mitred) then bolted into a metal nave. Its tyre is shrunk onto the rim in the usual way but it is also bolted on for security. A normal wagon wheel is dished so that in its lowest part, the spokes are perpendicular to the ground thus supporting the weight (with the axle
Wheel hub motor designs have minimized the electrical steel content of the motor by using a coreless design with Litz wire coil windings to reduce eddy current losses. This significantly reduces wheel motor weight and therefore unsprung weight. Another method used is to replace the cast iron friction brake assembly with a wheel motor assembly of similar weight. This results in no net gain in unsprung weight and provides a car capable of braking up to 1G. A good example of this is the Michelin Active Wheel motor as fitted to the Heuliez Will, the first electric car with an Active Wheel drive,