The Study And Application Of Multi-axis Controller For A New NC System

Along with the improving of the modern science and technology,the role of motor in application has been changed from the state of simple start-stop control that the only purpose was to supply power into the state of motion control that require accuracy control, such as velocity and displacement. In the filed of multi-axis application, multi-joint industrial robot or five-axis NC system for instance, multi-axis motion control has became critical technology which may influent the property of these products. This paper uses five-axis NC system as an example, by using the method of generating command pluses based on V-F transformer, proposes a new multi-axis numeric control method which can be use for multi-axis motion control system such as five-axis NC system and multi-joint industrial robot. The research on this paper can provide a new idea for developing multi-axis motion control system, high performance five-axis NC system with self-owned intellectual property.First of all, this paper introduces the mathematics fundamental of multi-axis motion control, which includes the description of the position and posture between space objects, coordinate transformation and homogeneous coordinate transformation. Next, the algorithms of interpolation pulse generating which adopt by the traditional NC system were included and the shortages of these algorithms when used in multi-axis simultaneous control were also reviewed by this paper.Secondly, On the basis of the analysis of traditional interpolation pulse generating algorithms, a new method of numeric control used for multi-axis simultaneous control was proposed by this paper. Using this method, an algorithm of real time pulse generating was used for generating command pluses which frequency can be changed timely. The principle of pulse generating, the parameters of this algorithm, steady-state error and algorithms correction were analyzed and described in detail. Evaluation was given to this algorithm by simulation.Next, the new multi-axis simultaneou numeric control method proposed by this paper was used in five-axis NC system, and this paper puts the emphasis on how to use this mathed to realize five-axis simultaneou control. Using this method, simultaneous control of five-axis NC system can be obtained directly. This method firstly builds the coordinate system base on five-axis NC system model. Forward kinematics of five-axis NC system can be obtained by using this coordinate system. And then, the driving velocity for each axis on five-axis NC system can be obtained by solving Jacobian and generalized inverse Jacobian. The simulation result shows the quantity of motion and numeric pulse series used for motor control of each axis can be obtained by this method, that means multi-axis simultaneou numeric control realize by this method.Finally, the new multi-axis simultaneou numeric control method was also used in multi-joint industrial robot for multi-axis simultaneou control. Simulation is given for the new method to realize six-joint industrial tipper moves along a space trajectory. The resule of simulation shows that the new multi-axis simultaneou numeric control method proposed by this paper can also be used in the domain of six-joint industrial robot.At the end of this paper, a conclusion of this research is given and the prospect of motion controller is discussed.