Design And Implementation Of The Embedded Real-time Control System For Intelligent Riding Platform

With the rapid development of China's economic and social development and the sports fitness industry,the indoor fitness,especially the spinning bike,a eco-friendly fitness equipment,has received wide attention from the society.In order to overcome the shortcoming of the current magnetic-resistive control system of stationary bicycle,such as unreasonable magnetic resistance regulation and unstable data transmission,an intelligent real-time control system for intelligent riding platform with high reliability and stability is designed.The design of software and hardware and the performance optimization are fulfilled as well.For the simplicity of the system maintenance and upgrade,the hardware circuit in the embedded real-time control system of the intelligent riding platform is separated into several modules,which improves the scalability of the system.These modules include STM32F411CEU6 minimum system circuit,power module,speed input capture module,magnetic-resistive control module,dynamic LED light control module,Bluetooth and ANT+ communication module,temperature detection and alarm module.In addition,the wireless communication adapter is designed to establish connection between the system and the virtual reality riding software of the computer client so as to achieve wireless data interaction.To realize the preset functional requirements and design indicators,the software of such the embedded real-time control system is designed based on the FreeRTOS real-time operating system.The software design consists of the FreeRTOS real-time system porting,peripheral driver,the speed input capture,the magnetic-resistive control and wireless communication program.Particularly,the system performance is optimized through a series of algorithms in programming.Firstly,the average limited filtering algorithm is proposed to stabilize the speed output of the system.Then,the polynomial regression method is applied to converse the speed value to the power value.Finally,the K-means clustering algorithm and the weighted average method are applied to obtain the duty radio of PWM corresponding to each gear of the riding platform.For the designed embedded real-time control system of the intelligent riding platform,the wireless communication,speed capture,gear position regulation,power output,high temperature alarm and compatibility are tested through a series of experiments.From the experimental results,it is shown that the embedded real-time control system can fit the output value well;the system has good real-time performance,reliability and output stability;virtual reality riding software has a good compatibility with different computer clients,which fully meets the preset functional requirements and performance indicators.