| Recently experts all over the world are engaged in the developing thefinish machining technique of free-form surface and there have been thespecial products sell in the market. Apply the virtual axis machine tooltechnique and human-imitated elasticity polishing technique to free-formauto-finish machining. Provide an idealized platform for human-imitatedelasticity polishing technique by using virtual axis machine tool. Thecharacteristics of the elastic polishing can relax the deficiency of thecomponent precision and the control precision that highly commanded byvirtual axis machine tool. With the mutual combination of the above two,this dissertation aims to develop a auto-polishing free-form surface specialmachine tool which can be applied to the practical production.The virtual machine tool comes from the theory of Stewart platform. Inthe late 1980s, countries like U.S.A. and Russia began to the research of thiskind of machine tool. This kind of machine has the characteristics of highstrength and weight ratio, high degree of modulization, high speed ofresponse, strong environmental adaptability, and the easy realization ofmulti-axes motion control, etc At the same time the hardware is very simple,the software is very complicated, and the technique is valuable. The virtualaxis machine tool is developed based on the theory of space parallelconnection organ Stewart platform. It is a new concept machine tool thatemerged recently. It is the product of the perfect combination of parallelrobot and machine tool and the high-tech output of the combination ofinterspace organ theory, manufacturing, numerical control, computersoftware and hardware technology and CAD/CAM. It overcame thelimitation that the traditional machine tool and can satisfy the machiningprocess of complex special type products.Fig 1 virtual axis polishing machine motion diagramThe essential difference control system between virtual axis polishingmachine and the traditional tool machine is that the movement in which thelathe has been used to operate is the non-linear reflection of the joint spacemovement. Therefore, PC completes all the coordinate transformation, thecontrail programming, interpolation operation, etc in this system. Yet thecontrol of multi-axis motion is completed by putting the motion controller cardinto computer bus (ISA bus and PCI bus) Multi-axis motion controller use ofthe high-speed processing ability of digital signal to complete the exactinterpolation of virtual machine, the I/O expand, the PID accommodate, etc.a great deal of data proceed equally operation of virtual machine.Motor motion controller connects #1 to #4 engines with each other. Wesetting the input and output address through intercalate register variableduring the period of motion control .The motion controller provides 16 bitregister during these period. We can find out the current axes completely bytransfer function which we have defined.PCI that is Component Interconnect of Peripheral bus is a popular busfacing the multimedia application. Nowadays it is the mainstream busstructure of the personal computer, and it has extensive prospects inembedded computer and industrial control computer application. Due to itsexcellent performance, such as bandwidth, power dissipation, noiseimmunity and opening property, PCI wins rapidly increasing popularizationand extensive applications. We design controller based on a deep study ofPCI bus specification. We designed and implemented in this thesis. Thehardware system for the controller card is constructed used the chip ofPCI9054. this designed controller, supporting burst transaction with allrequired PCI configuration register, is fully compatible to PCI busspecification V2.2. This paper designed a hardware of the chip card ofPCI9054 , enlarge the bus of motion controller I/O, and optimize the currenttheoretical map of bus and PCI bus design of power supply. The chip ofPCI9054 connect 16 data of extended board storage by the buffer74AC16245DL.With the help of the characteristics of free-form surfaces polishingmachine this paper use digital signal processor TMS320LF2812 as the focalprocessor on the basis of analyzing the movement of the machine and selectadvanced PCI bus communications, developed high-qualified, high–précised, embed motion controller which can be applied to free-formsurfaces polishing machine.The research of this dissertation can be summarized as followingseveral points:(1) We put forward the new approach of analog signal process and dataacquisition module design studied and given the design free-form surfacespolishing machine motion controller. At same time, we developed ourcontroller using TI embedded Digital Signal Processing chip ofTMS320F2812, which have high performance and good universal quality.Controller design compatible to PCI bus specification, which can control 1to 4 axes, output numerical digital pulse, Power and torque mix controlWhen applied to the free-form surfaces polishing machine the controller andachieve the three dimensional interpose and the two dimensional interposeof parallel connection organ of X axis, Y axis and Z axis .(2) In the hardware design of motor motion controller,we developedthe motor motion controller base on PCI bus. The paper designed the businterface of the chip PCI9054 of the motion controller. This system isdifferent from the traditional control one. The traditional system generallyadopts PC or PLC as attached machine, and achieves the control of theposition and speed by the communication data of the connection betweenPC bus and the attached machine. So the problems (transmit speed, on-spotcontrol, stability of the system) in traditional control system result innon-idealized performance of the controller. Yet the system developed inthis paper put the controller into the PC bus directly, improved theperformance of the chip, enlarge the I/O interface, expanded the capacity ofthe storage, simplified the current design and improved the communicationcapacity, so it can improve greatly the performance to the control system(3) In the design of the software, this paper makes use of theAPIfunction bank of PLX company to developed driver module ofcontroller, designed a hardware driver of circuit board, and carried out aintegrated debug. In this system, this paper achieved the function ofhigh-speed management of digital signal processor TMS320F2812, and atthe same time avoid the malpractice of on-spot performance and the signalinterfere that exist in traditional system. This paper provided a softwarebasis for optimized arithmetic that adopted in free-form surfaces polishingmachine.(4) This aper also put forward a new approach for the design offree-form surfaces polishing machine. The system mentioned in this paperapplied motion control chip TMS320F2812 of American TI company, makeuse of one chip to control tow axes, and achieved four axes control by usingtwo chips.
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