THE SCIENTIFIC BASIS BEHIND THE TECHNOLOGY
The principle of Monowheels is super simple and works on this easy way. For the forward or backward movement, the rider just leans slightly forward or backward. In order to steer left or right, the driver moves his body weight to the left or right.
1. How does the dynamic stabilization of the Monowheel works
The ability to independently maintain balance is the most amazing property on Monowheel and is the key to its operation. To understand how this system works, it is helpful to consider Kamen’s model for this utensil – the human body.
If you stand up and lean forward so far that you lose your balance, you nevertheless usually do not fall on your nose. The brain knows that you are not in balance, because of the fluid in your inner ear. So it causes you to put your foot forward, in order to avoid a fall. If you keep leaning forward, your brain will keep putting your legs forward. Instead of falling, you walk forward, one step after another.
The Monowheel does pretty much the same, with the difference that he has a foot instead of a wheel, instead of muscles a motor, a collection of microprocessors instead of a brain and a set of sophisticated equilibrium sensors instead of balance in the inner ear. Like your brain, the Monowheel knows when you are leaning forward. To maintain balance, it turns the wheel in exactly the right speed, so you move forward. Monowheel calls this behavior “dynamic stabilization”.
2. The brain and the muscles
The Monowheel consists of an intelligent network of sensors, mechanical components, a drive system and control systems. The moment when you step onto the unit, starting five gyroscopic sensors and two accelerometers 100 times per second to analyze the terrain and your body position.
Monowheel uses a special solid-state angular sensor. This type of gyroscope sensor judges the rotation of an object, taking account of the Coriolis effect on a very small scale.
With the Coriolis force is meant the effect, that moving bodies are deflected in a rotating reference system from the perspective of a co-rotating observer. If you observe a plane flying seemingly in a straight line, this line appears curved, because the earth moves under it.
The Monowheel has five gyroscopic sensors, though it would really only need three to control the weight transfer to the front and rear. The extra sensors add redundancy, to make the product more reliable. The information about the driver and his control weight shifting movements are passed along with the information of additional tilt angle sensors for “brain” of the Monowheels.
The “brain“ consists of two redundant electronic circuit boards which are each equipped with a group of microprocessors. The batteries and motor windings are duplicated. They work together and share the power required to drive the workload. The Monowheel has furthermore also some additional microprocessors. The Balance Scooter requires much calculating capacity because it must do precise calculations in the shortest possible time to prevent tipping. If a circuit board while driving fails (or the associated battery, motor windings or wiring), the other half takes over all functions. The system informs the driver of the fault and can be deactivated controlled.
The microprocessors are controlled by an advanced software, which in turn controls the vehicle. This program monitors all information arriving from the gyroscopic sensors and adjusts the speed of the electric motors. The electric motors, which are powered by two rechargeable lithium-ion batteries, can turn each wheel independently at different speeds.
If the vehicle is tilted forward, the motor will move forward the wheel to prevent overturning. If the vehicle is tilted to the back, the engine moves the wheel to the back.