The Study Of Fitness Load Control System Based On AC Servo Technology

In recent years, with the improvement of living standards, our national health awareness is growing and fitness enthusiasm is growing. Therefore going to gym has gradually become a part of life outside of work. The power-type exercise machines in domestic gym exists universal questions, such as wide noise, poor user experience and low level of automation. It is a important technical problems should be solved in the fitness equipment industry that how to apply modern advanced servo motor control technology into the fitness equipment to change the status that the current fitness equipment commonly used metal counterweight disk or a physical device to adjust the friction force to change strength grade and lead fitness equipment to a more intelligent direction.This paper based on the Shandong Huaya Industry Ltd’s subject of load control system of fitness equipment based on AC servo shows the relationship between fitness equipment and servo control system through the study of the control system of permanent magnet synchronous servo motor in the background of fitness equipment industry, on the basis of which the author design the exercise machine servo control system of permanent magnet synchronous motor as the load. The fitness torque servo control system consists of two major components of hardware and software. And, this paper discusses the design principle and the function of each part of the system.In the fitness load torque control side, due to the fitness of the motor mainly working in the stall, the torque output is not smooth. So, this paper bases on the mathematical analysis of the permanent magnet synchronous motor to establish the mathematical model firstly. Then the author use voltage space vector analysis method to decouple the mathematical model to get the theory of load control and achieve preliminary control of the load torque of fitness equipment.In order to ensure the smooth output torque, based on vector analysis, one fuzzy control algorithm which can predict the dynamic changes in the motor torque was designed. This paper describes vector analysis theory, fuzzy controller design principles and procedures as well as the structure and function block diagram of the fitness load controller. The recorded data of two group test shows that the dynamic stability of torque test with dynamic predictive fuzzy control algorithm is better than that one only with ordinary fuzzy algorithm, and the overshot of exercise machine servo control system with dynamic predictive algorithm of fuzzy is generally maintained at less than 6%. In terms of user experience, the actual torque offset can generally be maintained within 0.5Nm, and the offset error dropped by 50%, more smoothly torque output of the motor, eliminated the feel of frustrating before using of fuzzy algorithms. The method not only achieve the smooth control of fitness load torque in theory, but also has better the correction control effect in the actual test application, which can be widely used as the load torque control system for fitness related with servo motor.