| In recent years,the Internet of Things appliance market has become hot,and the Internet of Things drum washing machine has brought great convenience to people.The core of the Internet of Things is to connect things and things through the network for information communication,and realize the intelligent monitoring and management of things,the performance of the washing machine is directly related to the quality of the control technology.This article divides the development of the control system of the Internet of Things drum washing machine into a hardware circuit design part and a software design part.The motor in the drum washing machine uses a series-excited DC motor,which has the advantages of low cost,strong overload capacity,and easy speed adjustment,compared with existing washing machine drive motors,series-excited DC motors have obvious advantages.The paper analyzes the working principle of the series-excited DC motor and studies the control strategy of the series-excited DC motor.Constructed a PI closed-loop control system for series-excited DC motors,and Matlab/Simulink simulation software is used to simulate the PI closed-loop speed regulation system of the series-excited DC motor.Tune its PI parameters and apply it to software programming to control and adjust the speed of the motor.According to the technical requirements of the control system,the hardware design of the control system is completed with the STM32F103C8T6 chip as the control core.It mainly includes the functional design of the power supply circuit design module,series-excited DC motor control module,peripheral equipment control module and input signal detection module.The circuit schematic diagram and PCB design and production are completed using Cadence software.Build a hardware platform and test the hardware circuit to ensure the normal operation of the hardware circuit and provide a stable and reliable hardware working environment for the software design of the control system.Based on the above control strategy and hardware platform,the paper successfully transplanted the uC/OS-Ⅱ operating system,and based on this operating system,completed the system software design.It mainly includes uC/OS-Ⅱ system initialization,hardware initialization,signal detection,motor speed measurement and speed regulation,data communication,washing process processing and fault monitoring,etc.In this process,an efficient communication protocol is designed to realize the communication between the main control board of the washing machine and the cloud server.At the end of the thesis,the functional modules of the control system are tested.First,the speed regulation control experiment of the series-excited DC motor in the washing machine was carried out.After repeated experiments,the test results show that the motor can run smoothly and the control efficiency is high.Then send the corresponding washing instruction to the main control board of the washing machine,and the washing machine can work normally.Experimental results show that the control system meets the expected design requirements. |
