For the general Chinese people, the first time to know the electric self balance wheel will go back to the 2008 Olympic games. At that time, the stadium guards will ride the electric self balanceing wheel provided by the American Segway company as a patrol vehicle.
But at that time the self balance wheel is imported, this stops many peopel to buy this new product, so that the self balance wheel is covered with a layer of mystery. Today, we come together to explore the scientific principles behind the self balancing wheels, are you ready?
Working principle of the one wheel self balancing unicycle
Why self balance unicycle can keep stand:
On the one hand it is because people can adjust the focus, adjust the unicycle forward direction, the front line of the direction of change due to inertia will be able to balance the gravity torque. Another important point is that the high speed rotation of the wheel has a larger angular momentum, angular momentum can resist the external torque, like the gyro does not fall. In physics, this phenomenon is called precession, the torque direction autobiography physical rotation of 90 degrees.
Use the motor to enhance the balance:
On this basis, self balancing wheel is improved, driven by a motor, using it and keep driving circuit controlled gyroscope. The body can be tilted forward to start. Speed is controlled by the degree of tilt of the body, you want to speed up the forward tilt, slow down backward.
Aside from the active control of people, a single wheel balance unicycle to ensure normal work must be inseparable from the acceleration sensor and angular velocity sensor (Tuo Luoyi).
The acceleration sensor can measure the acceleration produced by the gravity of the earth or the motion of an object. Only need to measure one of the direction of the acceleration value can be calculated angle. For example, the use of X axial acceleration signal, when the car is upright, fixed acceleration in the horizontal direction of the X axis, when the output signal is zero bias voltage signal. When the vehicle is tilted, the acceleration of gravity g will form the acceleration component in the X axis, which will cause the change of the output signal.
But in the actual operation process of the car, because the slef balace hoverboard itself produced by the motion of the acceleration signal superimposed great interference generated in the measuring signal, the output signal can not accurately reflect the true dip. So the attitude information needed for the vertical control can not be obtained by the acceleration sensor.
Angular velocity sensor:
The rotating angular velocity gyroscope can be used to measure the object. Self balance hoverboard uses the gyroscope, you can measure the angular velocity of the vehicle tilt, the angular velocity signal can be integrated to get the car's tilt.
Core component of the self balance wheels:
When it comes to balance, we have to talk about the gyroscope. The principle of the gyroscope is that the direction of the axis of rotation of a rotating object does not change when it is not affected by an external force. According to this reason, people use it to keep the direction, what is called gyroscope. We ride a bike is actually using this principle.
The wheels turn faster is not easy, because the axle has a horizontal force. Gyroscope in the work to give it a force to make it rotate quickly, generally can reach hundreds of thousands of minutes per minute, you can work for a long time. The direction of the axis is then read in a variety of ways, and the data signal is automatically transmitted to the control system.
The acceleration and angular velocity of two sensors alone can not obtain dynamic condition accurately, stable posture, but these two kinds of sensors are complementary, the acceleration sensor used in static condition will be better, the use of gyroscope in the dynamic case, the effect will be better. At this point, we need an algorithm to effectively integrate the two signals to obtain accurate attitude information.
So the electric bluetooth hoverboard mainly through the controller (smart chip), attitude sensor (Tuo Luoyi), actuator (motor) to achieve the balance of three parts. When the driver body tilt, corresponding attitude sensor output attitude information, the controller aware of this information, the command to the corresponding motor rotation direction, the attitude sensor at a certain frequency constantly measuring car attitude and attitude information output to the controller, the rotation direction and speed controller constantly adjust the motor, so as to maintain a a dynamic balance.
The working principle of two wheel self balancing hoverboard
Compared with the single wheel balance unicycle, the biggest difference is more of a wheel and lever, but after it with the electric bicycle and motorcycle wheels arranged in different ways, but with two side-by-side fixed way, like a kind of two parallel robot. Two wheeled self balancing control system is a kind of two parallel arrangement, like the traditional inverted pendulum, it is a natural unstable body, must strengthen the powerful control means to make it stable. The utility model has the advantages of flexible movement, intelligent control, simple operation, energy saving, environmental protection, zero turning radius, etc. the utility model is suitable for running in narrow space.
The working principle of double wheel balance board is very similar to our own body. When the body center of gravity forward, in order to ensure a balance, we need to move forward and backward; when the center of gravity, we need to go back, which is the same reason.
When we are driving a self balancing hoverboard, the balance of the two wheels of the car instead of the feet. With the balance of the body system is very similar, when the center of gravity forward, intelligent system automatically sensed, and accurately drives the wheels to move forward, to keep the balance; similarly, when the center of gravity of our body tilt, the wheel will move backward.
This principle is called "dynamic balance" principle, which is called "the hoverboard balance causes the balance of the hoverboard"; sometimes called "the somatosensory hoverboard", this is because it can change the induction of the bodily center of gravity due to changes in driver attitude change running state; sometimes called "thinking hoverboard, this is because it can change, adjust the attitude and focus of intelligent intelligent induction condition.
The self balancing hover board using the "dynamic balance" principle, the second generation of motion compensation algorithm, the use of its internal gyroscope and accelerometer, to accurately detect small changes in body posture, and the precision of the servo control system, sensitive driving motor, make corresponding adjustment, in order to maintain the whole body stability and balance.
When we rotate the steering rod, the operating system will control the speed difference between the left and right sides, so as to realize the steering of the hoverboard body. Therefore, in the course of the ride, the direction of the joystick pointing to the direction you need to move forward, the hover board will be heading in the direction we point. When the steering lever is in the middle position of the hover board body, the system will move forward. And in the steering, if the body to follow the direction of the tilt of the steering lever tilt, then we will get a better steering experience.
Self balancing hoverboard not only has a fashionable cool appearance, there is an extreme precision intelligent operating system in its interior, with "show on the outside, the Hui in" to describe the most appropriate. But such a product has been shuttling in the regulatory gray area, parts of the traffic control department has restricted self balance hoverboard on the road, where the future will be towards the self-balancing board, is still not clear, and millet can be added to balance hover board industry into the track, everything is still unknown [Source].