Research On The Carpet Loom Control System Based On CAN Bus

Nowdays, with the standard of living improved,people tend to purchase carpet of good quality,and this current will go on performacing perfectly.However,as the domestic carpet manufactories are all small scale and short of capital ,they can't afford advanced carpet looms,and then,they all choose to upgrade their looms with introducing in advanced technology.This research comes of this condition.This research is to upgrade a loom of DongFeng carpet company.Last century ,a majority of domestic looms possess of controlling system with DCS and PLC+DCS,and the latter one is dominant.However,there is much shortage in PLC+PC system.It communicate with analog signals and this signals change very slowly,furthermore,it connect wires by one to on,so it is very difficult to make best use of the processor and improve calculating precision.The signals are badly immune to electromagnetism disturbance,furthermore,the old controlling systems are control by the computer companies.Theire products can't work in the same system.It is difficult to exchange theire products,and say nothing of construct a large scale communicating net.In order to resolve theses problems,this research introduce CAN BUS communicating technology, variable frequence variable voltage technology,step motor technology,inspecting on line technology and OOP technology.This research aims to improving the looms'working efficiency, constructing exoteric controlling system,improving automatization level,and easy to communicating with the system.In order to get these goals,this paper raise some research means:raising integrated control mode,hardware system design,software system design,field debugging and get some parameters.Raising integrated control mode.Firstly,this paper have analysed basal work rule of the loom and spin technics,then,analysed the primary control syetem of the loom,and raised itsshotage,and were't satisfied of modernization manufacture.In order to resolve this problem,this research introduced CAN BUS control syetem,then introducingCAN theory to discuss the control mode.This paper divided the control mode into five parts,that is PC part,figure data control part,step motor part,distance control part,speed control part.Every part has its function.PC part control and coordinate other parts,and it detect the malfunction of CAN BUS,deals with the malfunction,changes figure into data,transmits data to figure data control part through CAN BUS. Step motor part controls step motor.Figure data control part receives data from PC part,and transmit the data to the twenty four flip-latches. Flip-latches control solid-state relays,and these relays control clutches,then the carpet has protuberant and concave effect.Distance control part achieves where the neilsbed is,through detecting the signals of sensors,then,transmit data to step motor part and PC part.Speed control part changes the speed of AC motor by changing the frequence of transducer,then changes the speed of quick and slow axes.The five parts are connected by CAN BUS.Research on hardware of the system.The hardware theory of the five parts is discussed based on control mode,paving way for designing interfaces of hardware smoothly.This paper discussed detailedly the hardware of every part.Designing hardware is based the agreement of CAN BUS.Designing hardware include interface between PC and CAN net,interface between step motor and MCU,interface between transducer and MCU,interface between figure data control part circuit and MCU. Discussion on control method is based spin technics.In order to reach the goal,the frequence of transducer by introducing some mathematic method,and the drive frequence of step motor is changed correspondingly.This paper focuses on research on control method of step motor.Step motor is key to this control syetem,and the quality of carpet lie on step motor,so this research introduced detail control and speed'change control technology in controlling the step motor.Furthermore,speed changing on AC motor was discusseddetailly.firstly,analysing the work rule of speed control system,listing mathematic equation,getting primaryparameter.Research on software of the system.Designing software was based control mode , hardware and the agreement of CAN BUS.The format of transmitting data must accorded with CAN BUS agreement.The software of PC part divided into three part,and every part haved its function.They are initialization and parameter changing on line,detecting on line,figure data transmiting. The software of step motor was made for the detail control of step motor,and focused on discussion on control method of detail technology.The software of other part was same to step motor's software.Field debugging and get some parameters.In order to be satisfied of spin technics demand,This research want to get some parameters by field debugging. Besides,some useful parameters were acquired by changing the frequence of transducer and the frequence,two parameters of step motor on PC software's interface.Carpet companies may choose different parameters according as different technics.This paper combines research on theory and practice,and the function of the control system is satisfied of the goal raised on this research,and reaches the demand of spin technics.Finally,a conclusion can be bringed that the control system of loom based CAN BUS reaches the demand raised by DongFeng carpet company.Parameters can be changed on line according with technics and the loom can does the repeating work with advanced automation.