Programmable Multi-axis Controller Research Articles

Research on Compensation of Torque Ripple in Servo System

The identification and compensation methods of torque ripple based on steady state error analysis are presented in order to reduce the fluctuation of steady-state error of servo system and create environment for the accurate identification of the friction model.The relationship between steady state errors and input and interference of signals in servo system is determined.On this basis,the composition of steady state error for the uniform motion is researched.The steady state error induced by system disturbance including torque ripple,friction moment and others is obtained.The function form of torque ripple is obtained by using methods such as spectrum analysis and least squares criterion.The compensation of ripple can be achieved by programmable multi-axis controller(PMAC).The experimental results show that the fluctuation of steady state error decreases to different degrees.It has obvious effect at low speed;the peak-to-peak value reduces from 10 μm to 3.3 μm after compensation.At high speed,the peak-to-peak value also decreases to 3.2 μm after compensation.Besides,the Stribeck curve can be apparently acquired.Therefore,the method proposed can effective compensate the torque ripple and lay the foundation for precise compensation of friction disturbance and improvement of dynamic performance of servo system.

An Open CNC System Based on Motion Controller

Making a study of the design of a NC inserting PC open CNC system from the aspect of hardware and software, this paper adopted a programmable multi-axis controller (PMAC) to construct a hardware platform for the open CNC system on the mode of “PC + motion controller”. Introduction was made to a kind of way of implementation of the open CNC system. The developed system can satisfy the experimental requirements of the university’s numerical control laboratory and also be used to rebuild CNC systems.

Control system design and analysis of FRP pipe thread-grinding machine

The male thread manufacturing technology is a key factor that influences the production efficiency and the connection performance of large diameter Fibre Reinforced Plastic (FRP) pipes. The numerical control system of an FRP pipe thread-grinding machine based on Programmable Multi-Axis Controller (PMAC) and industry computer is described. The mechanical structure, the thread-processing technology and the development of the system are introduced. To eliminate the low-velocity creeping phenomenon, the friction dynamics of the radial servo control system is researched. Three key parameters that affect low-velocity motion performance are analysed, and some methods that improve the motion performance are put forward.

PMAC-based Tracking Control System for 8-axis Automated Tape-laying Machine

This article introduces a computer numerical control (CNC)-based open hardware architecture system to realize the special functions of automated tape-laying (ATL) in a numerical control system. It associates a programmable multi-axis controller (PMAC) as the motion control unit with programmable numerical controllers (PCL-725, PCL-730) for on-off control. To bring about synchronized movements of the main 5-axis tape-laying head system and the 3-axis ultrasonic tape-cutting sub-system, the tracking-control method associated with time-based mode attributed to PMAC is applied in different cases. In addition, with the goal of realizing real-time tasks in the software system such as synchronizing motion control and on-off control, the real-time Win 2000 system is adopted. As a device driver for PMAC and PCL, a user graphical interface and a numerical control program interpretation module are also designed. This system is helpful to solve complicated problems in designing numerical controls for ATL such as ensuring high requirements for precise machine control and synchronization of motion control and on-off control.

Research on the 3-Axis CNC Ultra-Precision Grinding of Aspheric Mould

Parallel grinding is an effective method of aspheric moulds machining which is usually made of industrial ceramic such as silicon carbide (SiC) or tungsten carbide (WC), but if the spherical grinding wheel is not being with precision truing and dressing, the roughness and form accuracy of the ground aspheric surface should get worse, for this reason, in this paper, the influence factors of thoroughness and form accuracy induced by the wheel truing and dressing are studied firstly, and a new 3-axis CNC Ultra-precision grinding system which is based on the PMAC (Programmable Multi-axes Controller) is developed, through simultaneous motion of the controlled X, Z and B axis, the form errors which is induced by the grinding wheel can be improved theoretically, and the aspheric mould machining test shown that the surface roughness of Ra 0.025μm and the form accuracy of P-V 1.15μm are achieved.

The Study on the Key Technology of Turbine Blade CNC Belt Grinding Machine

According to the structure features of turbine blade, the analysis of the grinding motion has been done and, based on the restriction conditions, the structural configuration of belt grinding machine has been described. Then the configuration of the control axis of belt grinding motion and the machine tool structure has been determined. The kinematics model of the blade grinding has been built by the motion control chain of the machine tool. The tool path algorithm of belt grinding has been proposed with STL 3D data model of blade surface. Based on IPC and Programmable Multi-Axis Controller PMAC, the CNC system of turbine blade belt grinding machine has been designed. Finally, the prototype of Turbine Blade CNC Belt Grinding Machine has been made.

Development of Parallel Grinding System of Aspheric Optics

The roughness and profiles accuracy of aspheric surface are two key factors affecting the resolution and other characteristics of optical instruments. In this paper a new grinding system-parallel grinding system was built, and an CNC system controlled by PMAC (programmable multi-axis controller) was developed, the parallel grinding system can realize Arc Envelope Grinding Method (AEGM) only through controlling 2-axis and the wear of wheel was diminished, the tool path calculation was simplified. Using this system, the roughness and profile accuracy of aspheric surface are improved.

Design on High-Speed Precision Grinder

As one of the modern manufacture technology, high-speed precision grinding takes an important part in the modern manufacture field. With the development of the technology on high-speed spindle unit, linear precision high-speed feed unit, manufacture of grinding wheel, measurement etc, a great deal of research achievements make it possible for high-speed precision grinding. In this paper, using PMAC (Programmable Multi-Axis Controller)—PC as the central controller, a new kind of high-speed precision grinder is designed and manufactured. The servo control technology of linear motor is investigated. The dynamic performances of the machine are analyzed according to the experimental results. Elliptical workpieces have been machined with this new high-speed precision grinder. Based on these research results, a very helpful approach is provided for the precision grinding of complicated workpieces, and these results promote the development of high speed grinding too.