Multi-axis Motion Control Research Articles

Design and Implementation of FFPIV Scheme for Closed Loop Motion Controller

To satisfy the requirements of motion control for industrial machine, a multi-axis motion controller based on DSP is developed in this paper. The motion controller consists of DSP which plays a main role in this design; DPRAM to make sure the rapid and reliable communication with host; FPGA to handle the task of address decoder and receiving feed-back encoder signal; and several peripheral logic circuits. In the part of hardware design, overall structure of motion control system is presented. Then, the Feed-Forward Proportional-Integral-Velocity (FFPIV) scheme which introduces KV in term of velocity loop to achieve the accurate, smooth and real-time response is proposed in the software developing part. The experiment data are carried out to indicate that this motion controller has advantages of superior performance and highly machining precision.

Research on Distributed Multi-Axis Motion Control System Based on CANopen

The 32-bit ARM Cortex-M3 core processor Stm32f107vc which integrates two sets of bxCAN interfaces is used as hardware platform to achieve the design of hardware module and software module in this paper. Firstly, real-time multi-tasking operating system μCOS-II is ported to stm32 processor, then open source protocol stack microCANopen which is high real-time and reliable is transplanted under the μCOS-II, so a design of CANopen slave station is achieved. The CAN analyzer which is equipped with monitor trace functionality is used as CANopen master station to start the network, with three CANopen slave stations and one HMI, a distributed multi-axis motion control system based on CANopen which achieves network management and synchronous transmission of data in distributed control system is designed. On above basis, Fuji ALPHA5 Smart servo is used as executive member, modular design of reconfigurable motion control algorithm is realized, furthermore, The flexible module configuration enables the designer to develop systems conveniently according to the change of control requirement and network topology. This distributed control system not only has good real-time performance and stability, but also can reduce the complexity, enhance the flexibility of control system and save cost.

An integrated CNC accumulation system for automatic building-around-inserts

In this paper a non-layer-based additive manufacturing (AM) process named computer numerically controlled (CNC) accumulation process is presented for applications such as plastic part repairing and modification. To facilitate the CNC accumulation process, a novel three-dimensional (3D) laser scanning system based on a micro-electro-mechanical system (MEMS) device is developed for in situ scanning of inserted components. The integration of the scanning system in the CNC accumulation process enables the building-around-inserts with little human efforts. A point processing method based on the algebraic point set surface (APSS) fitting and layered depth-normal image (LDNI) representation is developed for converting the scanning points into triangular meshes. The newly developed 3D scanning system is compact and has sufficient accuracy for the CNC accumulation process. Based on the constructed surface model, data processing operations including multi-axis tool path planning and motion control are also investigated. Multiple test cases are performed to illustrate the capability of the integrated CNC accumulation process on addressing the requirements of building-around-inserts.

Implementation of Multi-Axis Motion Controller by FPGA-Based Hardware Design

Implementation of Multi-Axis Motion Controller by FPGA-Based Hardware Design

To Develop a Parallel Processing System with the FPGA for Multi-Axis Motion Control Platform

It is known that the flexibility and programmable abilities have made the FPGA widely used as controllers to the electrical machines and systems. Above all, the high density of recent developed chip results in many of the CPU cores and complicated hardware can be programmed into the chip to be as controller. Thus, this topic is based on the currently available technologies of FPGA-based system design to the parallel processing. Software and hardware co-design are shown to reach the performance, and the system’s software stream data are processed with the hardware parallel technique. This analysis enables FPGA-based control system on the parallel computing platform to achieve the simultaneous operation for 3-axis motor motion and drive system control. In that way, we chose the high density FPGA, Altera Cyclone II EP2C8Q208C8N, as the chip to develop the hardware of microprocessor, motor drive and motion controller. The developed system was practically applied to a 3-axis motion platform driven by stepping motors to evaluate the system performance.

The Research of Real-Time Trajectory Interpolation Based on Open Numerical Control System

This paper researches on Open Numerical Control System based on the PC platform, in which the motion controller works as the control core, can realize the multiaxis motion control in real time and the sequential logic control. This paper sets out from the hardware structure, use the Real-time trajectory interpolation algorithm, and choose the proper motion-control function. it can realize fast, stable and continuous movement with multistage path, and ensure that the system is open, real-time and reconfigurable.

Multi-axis motion controller for robotic applications implemented on an FPGA

This paper presents the design of a field-programmable gate array (FPGA)-based motion controller for robotic applications. In contrast to digital signal processor and microprocessor implementations, the control period of this system is fixed. Foregoing implementations on FPGA require microprocessor-based platforms for data interchange tasks consuming a large amount of resources; consequently, they could not be implemented on low logic density devices, or they use IP cores which limits the implementation of the system to only certain device families. This new motion controller architecture integrates control and communication modules in a single chip which permits an increase to the number of axis according to the system requirements. The proposed design presents a low consumption of logic resources; therefore, a considerable cost saving per axis is achieved. The system test has been carried out with a three-degree of freedom selective compliant assembly robot arm robot and a standard PC as master device. The digital filter parameters have been tuned by using a crossover frequency method. Step and profiled motion responses obtained show very good performance.

Study on Open CNC Control System Based on GUC Motion Controller

This paper mainly focuses on designing an open CNC system. At first, the advantages and disadvantages of the three popular open numerical control technologies were discussed, and on the basis of demands analysis, this paper chose motion controller plus PC as the whole system model. Then, according to the system model, this article designed the hardware system for the control system, including choosing multi-axis motion control card, servo motors and their drivers. Thirdly, based on the features of this open numerical control system, the paper designed and put the software into three levels, namely low level of control software, mid-level of communication software, and high-level of management software respectively. Finally, in order to test the control performance of this open numerical control system, some experiments were carried out on a two-dimension motion platform, the results are satisfactory and error analysis on these experiments is also given out.

Study of the Multi-Axis Motion Controller Based on DSP

According to the development and current situation of DSP (Digital Signal Processing) at home and abroad, using high-speed computation ability and rich resources of TMS320F28335 chip to achieve higher real-time demand motion control in numerical control system (linear interpolation, continuous interpolation, position control, Serial communication, etc). On that basis, this paper discusses realization of hardware and software design method of this controller. Such movement controller has the perfect function and excellent performance, it often provides the multi-axis motion coordination control on the plate, and has higher control precision.

The PID Control System for the Electric Buses Battery Swap Robot

In order to meet the development of the domestic electric car and to adapt to changes in the height of the bus to avoid damage to the battery and the body of the bus in the process of changing batteries, this paper designs a robotic system based on dynamics visual servo control system for the electric buses battery swap robot following the target, The robot consists of X, Y, Z three freedoms and the R-axis, T-axis freedoms which can adjust the battery angle relative to vehicle chassis and follow the changes of the height of the bus. In this paper, we design the robot using of robot dynamics visual servo technology, path planning, multi-axis motion control technology, multi-sensor technology and PID control theory. The system is stable, reliable and can rapidly follow the changes of the height of the bus by the system debugging and trial operation, achieving a rapid supply of energy to electric buses.

보현산천문대 1.8 m 망원경 제어시스템 현황 및 개선방안

We analyzed the current status of the telescope control system (TCS2) of the 1.8 m telescope in Bohyunsan Optical Astronomy Observatory (BOAO), and suggest a new TCS (TCS3) for the long term development of BOAO. The TCS2 was constructed in 1998 to replace the TCS1 which was installed with the telescope itself at the commencement of BOAO. One of the important parts of TCS is PMAC (Programmable Multi-Axis Controller), which is a general-purpose multi-axis motion controller. PMAC provides the direct interactive communication environment permitting users to command the controller directly with simple operations. This makes the setup, debugging, and diagnostics very easy. The TCS2 was operated stable for a long time, but the hardware and TCS computers have been deteriorated and are out of date now. The new TCS3 needs to be constructed based on a modern computer system. And functions such as pre-calculations of telescope limiting position, interworking with virtual observatory tools, and using GUI, etc should be added. Construction of the TCS3 will be a step creating a better observation environment for the Korean astronomical society.

The Applied Research of Four Polynomial Acceleration and Deceleration Control Method in Multi-Axis DSP Motion Controller

In traditional NC systems, the linear, index and S curve acceleration and deceleration control methods exist lots of problems that jerk is discontinuous or algorithm is too complex, seeking a more superior acceleration and deceleration control method to make up these shortages is needed. In this paper, the Four polynomial acceleration and deceleration control method is researched further, some contrast experiments have been done on NC terrace which is based on 32 bit floating point multi-axis DSP motion controller, and the superiority of this method and the practicability in NC field are analysed by processing two hemispheres with H600 CNC engraving and milling machine.

An Open-Access Educational Tool for Teaching Motion Dynamics in Multi-Axis Servomotor Control

Servomotors are widely used in computerized numerically controlled (CNC) machines, hence motion control is a major topic covered in undergraduate/graduate engineering courses. Despite the fact that several syllabi include the motion dynamics topic in their courses, there are neither suitable tools available for designing and simulating multi-axis motion control nor an efficient link between theory and practice. This paper proposes an educational, open-source tool for teaching motion dynamics in multi-axis servomotor control. The tool allows students to generate multi-axis motion and export these movements for their application to a CNC machine. A simulation module is embedded for evaluating the controller performance. The proposed educational tool allows the use of the inductive pedagogic method to support student learning. Eleven lab practicals are described to show how the proposed tool can be utilized for the systematic teaching of motion dynamics.

Design and Implementation of a Delay-Guaranteed Motor Drive for Precision Motion Control

This paper proposes a systematic design approach for a precision-guaranteed motion control system. We develop a delay-guaranteed motor drive with our new software implementation and real-time Ethernet, which can be used as a building block to build up a multi-axis motion control system. Our drive software implementation provides a probabilistic guarantee on drive-local processing delays to motor actuation, while real-time Ethernet provides a deterministic guarantee on message communication delays from a motion control host to each drive. In the paper, we address the precision of a motion control system in two terms: host cycle time and simultaneous actuation deviation. The host cycle time is a period with which the host can periodically release motor control messages while the average drive utilization does not exceed 1, and the simultaneous actuation deviation is the difference between the earliest and the latest actuation at different drives in response to the same message. In our approach, the main objective is to minimize the periods of tasks in each drive, using our stochastic analysis, which gives us a minimum possible host cycle time. Together with an existing delay analysis of real-time Ethernet, we analyze the end-to-end delay from message release to motor actuation and in turn the simultaneous actuation deviation. Through experiments, we show that for various requirements on the deadline miss probabilities of the tasks, we can successfully reduce the host cycle time and evaluate the resulting distribution of the simultaneous actuation deviation depending on the number of drives.

Development of a real-time laser-based machine vision system to monitor and control welding processes

In this study, a laser-based machine vision system is developed and implemented to monitor and control welding processes. The system consists of three main modules: a laser-based vision sensor module, an image processing module, and a multi-axis motion control module. The laser-based vision sensor is designed and fabricated based on the principle of laser triangulation. By developing and implementing a new image processing algorithm on the platform of LabVIEW, the image processing module is capable of processing the images captured by the vision sensor, identifying the different types of weld joints, and detecting the feature points. Based on the detected feature points, the position information and geometrical features of the weld joint such as its depth, width, plates mismatch, and cross-sectional area can be obtained and monitored in real time. Meanwhile, by feeding these data into the multi-axis motion control module, a non-contact seam tracking is achieved by adaptively adjusting the position of the welding torch with respect to the depth and width variations of the weld joint. A 3D profile of the weld joint is also obtained in real time for the purposes of in-process weld joint monitoring and post-weld quality inspection. The results indicate that the developed laser-based machine vision system can be well suited for the measurement of weld joint geometrical features, seam tracking, and 3D profiling.

Design of Multi-Axis Motion Controlled System Based on SERCOS Bus

SERCOS is an international standard for communication in the digital servo system and electrical drives. It has been increasingly used in industrial automation equipment. This paper introduces the working principle and property of the SERCOS interface, and the SERCOS bus technology is used in the multi-axis motion control system. The PC coordinately control the slave computer through SERCOS bus. At the same time, PC will receive the feedback information of motion parameters timely, which can enhance the flexibility of the control system. SERCOS realizes the multi-axis motion based on the TwinCAT software platform, which has verified the rationality and feasibility of the control structure.

A hardware–software system for coordinated multi-axis control based on a non uniform rational B-splines interpolator applied to industrial computer numerically controlled machines

Motion controllers are widely used in many mechatronic applications such as computer numerically controlled machine tools and robots. These applications demand the use of high performance controllers. Some desirable characteristics in motion controllers are coordinated multi-axis control, smooth movements, and advanced interpolation methods. An important manufacturing aspect involves the production of a workpiece in a free form or using the parametric surfaces in modern computer aided design/computer aided manufacturing systems. The use of parametric curves and surfaces has become standard due to their ability to represent objects having complex surfaces with less data. Another mandatory characteristic of motion controllers is the real-time operation. The contribution of the present work is the design and implementation of a hardware–software system for multi-axis motion control featuring non uniform rational B-splines interpolation. Advantages over other reported works are the hardware implementation which allows the application to real computer numerically controlled machines; also the parallel processing permits the incorporation of additional modules to form an integral system without dependence on external devices. Two experiments were carried out in a retrofitted-to-computer numeric control milling machine in order to show the efficiency of the developed system.

Design of Interpolation Algorithm in the Multi-Axis Motion Control System

This paper describes an interpolation algorithm in the multi-axis motion control system, which can achieve six-axis interpolation operations, greatly improving the processing efficiency. Using modular design idea on the Quartus II platform, by DDA interpolation theory, interpolation modules are built through VHDL. And these interpolator modules are connected into schematic diagrams. By those schematic diagrams a linear interpolator, a circular interpolator and a composite interpolator are formed. The corresponding functions of those interpolators have been simulated on the Quartus II platform. The simulation shows that this interpolation algorithm is effective to complex multi-axis motion control system.

Study on the Multi-Axis Motion Control System Based on Ether CAT

Now, the complication and systemization of the industry is increasing day after day, which make it hard to design the motion control system. However, the technology of field control is increasing, and the motion control system based on the network is widely used. The company of beck Hoff introduced the Ether CAT network, which can be configured easily, and the speed of communication is high, and in some way, the technology has become the focus of the studying the automation. This paper analyst the application for the Ether CAT in the multi-axis motion control system.

Study on the Multi-Axis Motion Control Based on LabVIEW

On the basis of study on the key multi-axis motion control theories about acceleration & deceleration control, numerical interpolation algorithm, device drivers and application design technologies based on LabVIEW, verified the feasibility through the 3-axis numerical milling platform developed by ourselves. The platform can also realize the simulation and practical verification about the demonstration teaching process of numerical control machining and 3-dimensional contour of the workpiece machined, and has the significant practical value.