Now, I will explain about a wheel using an Inverse Magnetostrictive Effect. The YouTube video will help you to understanding the invention.
This wheel generates torque by using the inverse magnetostrictive effect. First, I will explain about the inverse magnetostrictive effect. As the magnetostrictive material, there is an iron-gallium alloy. As with iron, the magnetostrictive material has the property that is attracted to the magnet as shown in Figure 3(b). As shown in Figure 3(c), the property that is attracted to the magnet will be weakened when a stress is applied to the magnetostrictive material.
As shown in Figure 1(b), an inside magnetic flux density varies greatly when the stress is applied to the iron-gallium alloy. For example, the inside magnetic flux density will change about 1 Tesla.
Next, I will explain about a wheel. Make spokes of the wheel from the iron-gallium alloy as shown in Figure 1(a). Place a magnet next to the wheel. The spokes are attracted to the magnet.
As shown in Figure 3(a), heavy weight of a train will take to the wheels. A reaction force is applied to each wheel by a rail. As shown in Figure 2(a), the property that is attracted to the magnet of a spoke M1 will be weakened when the reaction force (i.e. stress) is applied to the spoke M1. Other spokes M2-M4 are strongly attracted to the magnet. For that reason, the wheel rotates in a counterclockwise fashion.
Wheel rotation swaps the positions of the spokes M1 and M2 as shown in Figure 2(b)-(c). Accordingly, the stress will be applied to the spoke M2. The property that is attracted to the magnet of the spoke M2 will be weakened. Other spokes M3-M5 is strongly attracted to the magnet. For that reason, the wheel rotates in the counterclockwise fashion. Repeat the same motion, the wheel will continue to rotate.
A wheel is a great invention in the history of mankind. We can carry heavy objects with a small force. This is because a rolling resistance of the wheel is very small. For example, a force required to rotate a wheel of a railway train is just 0.2kgf-1.0kgf per train weight 1000kg. When a rotative force is greater than the rolling resistance, the wheel will rotate.
As discussed, the inside magnetic flux density varies greatly when the stress is applied to the magnetostrictive material. The force to rotate the wheel can be generated by the magnetostrictive material.
Compressibility of the magnetostrictive material is very small, so it hardly deformed. Therefore, the rolling resistance of the wheel is very small. Also, the iron-gallium alloy is hard to break. While a center of gravity of the wheel is kept substantively a center of the wheel, bias occurs in the intensity distribution of the magnetization in the wheel. Without entering the energy from outside, the wheel continues to rotate.