The Design For Twister Controller Based On Modbus

With the improvement of living standards,people persuit better surface finish. Raw silk produced through the twister twisting the fabric of crape to produce crepe effects, not only the visual appearance of the fabric is more soft, but also the crepe bump makes a more gentle contact with human body .It brings a good sense of cool and comfort to people. The crepe fabric has become more and more popular to people, and its developed varieties are also more and more, to this end, Twister has been welcomed by a number of textile mills. After several years'exploration, the continuous development of domestic twisted production technology is close to the international advanced level, but the ability of independent research on twister electronic control technology is still relatively weak, and twister electric control system still has much more room for progress in its stability and functional diversity.In this paper, on the basis of present domestic twisted production technology, combined with the computer, electronics, automatic control, sensors, data transmission, frequency control techniques, using a distributed control scheme, a set of twister automatic control system is designed with humanized operation interface and rich functionality. It replaces the conventional touch-screen &PLC structure, not only reduces the production cost of the controller, increases the system integration, but also greatly enriched the system control functions. The control system is mainly divided into two parts, host computer system and lower position machine system. Host computer systems uses Intel's high-performance embedded processor PXA270 as core, running Windows CE4.2 operating system, mainly to set the most important parameters in twisted production technology, record the state of the running machine, and can perform real-time control on lower position machine through high-speed SPI communication interface. Lower position machine system USE Freescale's 8 bits industrial grade MCU as control core, have the basic functions of general industrial control PLC ,mainly to complete the analog voltage signal sampling, switch output, high speed and low speed pulse frequency sampling, and supports the MODBUS protocol. It controls twister's speed control system and single-spindle controller through the RS-485 bus. The communication between host computer and lower position machine also adopts the MODBUS protocol. Lower position machine measure the motor speed by pulse sampling circuit, and performs closed-loop control over motor's speed according to AC motor inverter control command. Host computer, as master device, visits lower position machine, sends speed and temperature control command to it, and carries on coordination control to speed control system and spindle yarn temperature.This study has made a solider foundation for the achievement of twister automated production. It has important practical significance and application prospects. After Twister manufacturers actual test, system's functions and indicators all have met the design requirements.