23 Jun 2021
A fountain is a combination of a specific shape that sprays water or other liquids through a nozzle under a certain pressure. Current fountains are generally artificial fountains that rely entirely on fountain equipment. The main thing is to realize the rhythm and rhythm through the control of the frequency converter. The water shape changes in the music fountain is rich, and the lighting gives people a real and intuitive beauty. The various swings in the musical fountain can make people feel the soft beauty of the fountain. The generation of radial swing is due to the setting of a swing mechanism under the water surface, which makes the waterscape beautiful, pleasing to the eye, and gives people a magical feeling. It is a manifestation of the high-tech development of the times.
The position and movement speed of the swinging fountain are the important factors that produce the swaying water-shaped chic charm. The position sensor of the fountain swing mechanism should be a waterproof and non-contact positioning device. Hall sensors induced by magnets, photoelectric sensors guided by optical fibers, or rotary position encoders attracted by magnets are often used. For example, the positioning device of a fountain swing mechanism using a position encoder includes: a position encoder mounted on the swing motor shaft, a high-speed counter, a control computer, and a communication interface. Since the connecting rod of the swing mechanism generally has a large gap, in order to achieve accurate positioning, the swing mechanism can only reach the positioning point from one direction to ensure its repeatability. Therefore, when the swing mechanism needs to stop, it must reach the positioning point from one direction every time.
The positioning accuracy of the rocking mechanism is affected by the movement torque and the resistance torque. The movement torque is determined by the power supply voltage of the motor and the movement speed before stopping, while the resistance torque is synthesized by the friction of the swing mechanism, the speed of the water flow, and the surrounding wind. It can be seen that these are all factors that cannot be determined in advance. Therefore, in order to achieve precise positioning, we must change its control parameters every time. There are generally two control parameters for precise positioning using motor energy consumption braking, the magnitude of the DC braking current and the starting braking time. The more convenient way for computer control is to change the braking time.
In the control system, the braking time of the motor can be corrected by the deviation of the detected position. According to the statistical data of the positioning deviation of the swing mechanism and the calculation of the mathematical model, the braking time is finally determined.
Originally published 23 Jun 2021, updated 23 Jun 2021.