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Proceedings of the 2009 IEEEInternational Conference on Mechatronics and AutomationAugust 9-12, Changchun, ChinaA New Reconfigurable Logic for CNC Lathe ControllersJingchuan Dong+, Yunfeng Wang*, Zijing Wang+ , Taiyong Wang+978-1-4244-2693-5/09/S25.00 2009 IEEE2835Advanced Manufacturing Technologiesand Equipments Laboratory +Tianjin University, Tianjin, 300072, Chinanew_lightningyahoo.com.cnAbstract - Reconfigurable devices have been developed to implement the control algorithms in Computer Numerically Controlled (CNC) systems recently. Reconfigurable devices provide high execution performance of CNC and flexibilities to the system design. However, little work was done on the implementation of reconfigurable logic in a CNC lathe. This paper developed a new resampling algorithm for the synchronized movement in threading and a reconfigurable logic in a CNC lathe. An experimental system was constructed and the test results validated the proposed architecture.Index Terms - CNC lathe, reconfigurable logic, resample, threadingI. IntroductionComputer Numerically Controlled (CNC) machines are widely applied in modem industries. As the control center of the machine, the CNC controller affects the machining performance in many aspects such as speed, precision and stability. With the rapid increment in machining speed and precision, the conventional software based CNC controllers are difficult to meet the computational demands. The reconfigurable hardware is introduced to solve this problem.The reconfigurable hardware facilitates the CNC system in many ways. First, the control algorithms can be implemented by hardware with a high execution performance. The designer can take the advantage of the parallel structure of the hardware to accelerate the algorithm. In addition, the realtime execution ability of the hardware is ideal to realize the control laws efficiently. Second, the reconfigurable hardware provides flexibility for the designers. Due to the programmable characteristic of reconfigurable hardware, the designer can integrate varieties of custom circles into a single chip easily and rapidly. Third, the reconfigurable hardware provides the possibility to modify or update the hardware design in the previous version. Even if the controller has been delivered to the user, the hardware logic can still be modified to meet new requirements.The research on the reconfigurable hardware in motion control systems have been published recently. Some work focuses on the design of position controller. Chan et al. implement the PID control algorithm on a Field Programmable Gate Array (FPGA) using a Distributed Arithmetic (DA) scheme 1. Tao et al. append a three-grade position feedforward to the hardware PID controller 2. Zhao et al. compares different structure of PID controller for multi-Department of Mechanical Engineering*The College of New JerseyEwing, NJ 08534, USAjwangtcnj.educhannel control 3. Wang et al. designed a FPGA based neural network PID controller 4. Su et al. implemented the digital difference analyzer (DDA) control algorithm on a FPGA chip 5. Other functions in CNC controllers have also been studied. Osomio-Rios et al. implement a hardware polynomial-based profile generator with jerk limitation for CNC and robotics applications 6. Yau et al. implemented real-time NURBS interpolation algorithm on a FPGA 7. However, there is lack of work on implementing reconfigurable devices for the CNC lathe controller, which is the focus of this paper.This paper developed a new resampling algorithm for the synchronized movement in threading and a reconfigurable logic in a CNC lathe. This paper will be structured as follows; In Section 2, the architecture of a CNC controller and the threading process will be discussed; In Section 3, the principle of the resampling method will be introduced; In Section 4, the hardware design of the reconfigurable logic will be described; In section 5, an example of CNC lathe controller using the proposed method will be presented.II. BackgroundA. The Architecture of CNC ControllerThe architecture of a CNC controller is shown in Fig. 1. The architecture includes four control layers 8: intelligent control, motion control, device control and physical device. The Human-Machine Interface (HMI) interacts with the operator, and calls the intelligent control layer to do the machining job. In the intelligent control layer, the input NC program is interpreted into machine instructions. The machine instructions are executed by the motion control layer, which consists of an interpolator and a discrete event control module. The interpolator generates position commands according to the desired motion instructions and speed profile. Other instructions, such as tool selection and coolant control, are handled by the discrete event control module. The device control layer operates the physical devices to realize the machining process. It incorporates an axis control module and a discrete input/output control module. In the study of this paper, the device control layer is implemented by using a reconfigurable device.Fig. 1 Architecture of a CNC controller.For a CNC lathe, the motion functions fall into two categories: the normal motion and the spindle synchronized motion. The normal motion is used in profile machining, while the spindle synchronized motion is used in the threading process. The principle of normal motion is similar to the motion in a milling machine, which has been successfully realized on reconfigurable devices by other researchers. This paper concentrates on the reconflgurable hardware for the spindle synchronized motion.B. Threading on a CNC LatheTo maintain the threading accuracy, the feed motion must synchronize with the spindle rotation as shown in (1). F is the feed speed (mm/min), S is the spindle speed (rpm) and L is the lead of the thread (mm).F = SxL(1)An incremental rotary encoder is attached to the spindle to determine its angular position. As the spindle rotates, the encoder generates two channels (A and B) of signals that are shifted 90 degrees out of phase from each other as shown in Fig. 2. By monitoring the number of pulses and the relative phase of A and B channel, both position and rotate direction can be tracked. The encoder also provides an index signal, which pulses once per revolution, as the reference point of the angular position.Fig. 2 Waveform of the rotary encoder.Fig. 3 shows an example of the cutter path in threading process 9. While the spindle rotates, the cutter moves to the points 1. Then, the controller waits for the index signal to determinate the absolute position of the spindle. Once the spindle rotates to the required position, the threading process will begin with the acceleration movement in the feed direction. During the acceleration, the thread is not precision. When the acceleration end at point 2, the feed speed arrives at the desired speed and the feed movement will synchronize with the spindle. Before the end of threading process, the cutter will begin decelerating at point 3. The thread is also not precision during the deceleration. Finally, the threading process stops at point 4 and the cutter moves away from the workpiece.Fig. 3 An example of threading process.The spindle speed may fluctuate in the threading process. According to (1), the feed speed should follow to the spindle speed. The threading process may take several passes in order to limit the material removal rate or create multiple start threads. The lead may also change in a special thread. Therefore, in the threading process, the movement along the feed axis must synchronize with the angular position of the spindle. The traditional method to solve this problem can be described as following steps:1) In each motor control cycle, sample the spindle position.2) Call the interpolator to calculate the new cutter position according to the thread profile.3) Update the command position for each axis.4) Return to step 1 if the threading process is not done.The above steps must be executed in one motor controlcycle each time, thus all the steps must done in real-time. However, if the real-time execution is performed by software, the overhead of the control algorithm is high, and it is hard to achieve a short control cycle. Besides, the real-time software execution needs extra CPU time as to switch between the realtime tasks and other tasks. The proportion of the CPU time spends on the task switch will be very large if the control cycle is relatively short.III. The Resampling Method2836In our work, the resampling method is proposed to avoid the real-time execution of the interpolation algorithm when threading. Moreover, the reconfigurable hardware is employedT =K(8)for the motor control and other real-time functions. Fig. 4 demonstrates the principle of the resampling method:A Position generated byFig. 4 Principle of the resampling method.1) The interpolator assumes the spindle runs at a constant speed. Therefore, in each cycle, the spindle rotates a fixed degree A(pT . Then the interpolator can sample the cutter position with the constant step size A(pT according to the thread profile. Because the interpolator doesnt need the actual spindle position, the interpolation could be done before the real motor control cycle.2) In the motor control cycle, the position command is generated by resampling the position curve. The position curve is reconstructed by connecting each interpolated position using straight line. Although the increment of the spindle angular position may change, the command position can be obtained by the resampling.The position of the spindle is measured by counting the pulses from the rotary encoder. Therefore, the increment of the spindle position in each motor control cycle is the integral multiple of the pulse equivalent. We can chooseIsxp、= KE,(2)where E is the pulse equivalent of the spindle encoder and is a positive integer. Assuming at the two successive interpolating times the spindle positions are q)n and (pn+x, andthe correspondent interpolated positions for the feed axis are An and An+1, since the position curve is reconstructed bylinear function, the position function in the interval can be written as= An+1 - AnAs the spindle position is represent by the counts of encoder pulses, the (p in (3) can only take discrete values. Letg = g)m=g)n+mE,m =.(4)Substituting (2) and (4) into (3), we obtainA(Pm) = A =(5)KEquation (5) can be further written in incremental formjpm+i) = 4pm) + 4mbit adder is used2838to do the addition operation in (6). Every time the ADD CLK signal comes, REG1 latches the result of the addition. If the motor controller requires the increment of next commandREG2position, the OUT LOAD signal will goes high. Then, the resampled position, i.e. the higher 8-bits value of REG1, is latched to REG2. The OUT LOAD signal also clears the higher 8-bits of REG 1. Therefore, the value in REG1 is the increment of position command.Fig. 7 Structure of the resampler.V. Experimental VerificationA CNC lathe controller was built to test the proposed control method. The diagram of the experimental CNC system is shown in Fig. 8. The system consists of two parts: the nonreal-time part and the real-time one. The non-real-time part includes a 32-bit ARM 920T microprocessor, a flash memory, a SDRAM, communication ports and a debug unit. The nonreal-time part runs the Linux operating system. The control software includes the user interface, interpreter, interpolator, sequential logic, communication, NC file management and other functions. The hardware of the real-time part includes a 8-bit AVR microcontroller, a dual port RAM, a FPGA chip, a D/A converter and the circuits for signal conversion and isolation. The dual port RAM is used to buffer the real-time control commands, which includes the interpolated positions. The AVR microprocessor was used to fetch the control commands and send them to the FPGA and spindle D/A converter in real-time. The reconflgurable control logic was implemented on the FPGA. The D/A spindle converter controls the spindle speed. Fig. 9 shows the hardware setup of the CNC controller. To the CNC lathe Fig. 8 Diagram of the experimental system.Fig. 9 Hardware setup of the controller. TABLE IParameters of the test threadsParameterTest 1Test 2Test 3Majordiameter (mm)202216-22Minordiameter (mm)18.420.414.4-20.4Length (mm)303030Lead (mm)1.531.5Pitch (mm)1.51.51.5Taper rate000.2CommentSingle-start straight threadDouble-start straight threadSingle-start tapered thread2839In the experimental system, the resolution of the spindle encoder was 4800 pulses per revolution (after quadruple). The motor control cycle is 1.02 milliseconds. Several machining programs were tested on this controller to examine the proposed reconflgurable logic. A profiling program tested the straight and arc feed functions in the normal control mode, while three other programs verified the resampling algorithm in the threading mode. The parameters of the threads are listed in table I. In the threading tests, the spindle speed was programmed to 500 rpm, and the actual speed was between 486.4 to 518.5 rpm. According to (8), the equivalent interpolation cycle in the test was 0.8 milliseconds. Fig. 10 shows the threading process in the test. Fig. 11 shows the finished parts. All of the test programs worked as expected. The results show that the proposed architecture is feasible to the CNC lathe controller.Fig. 10 Threading process.Fig. 11 Finished parts.It is notable that, by utilizing the reconfigurable logic, the motor control task and resampling algorithm could be done by hardware. The reconfigurable hardware enhances the CNC system performance. Moreover, this architecture allows the interpolated points to be calculated before the threading, thus eliminates the need to run the interpolator in real-time. By running interpolation in a batch mode, the overhead in the real-time context switch is reduced, and a higher data throughput is possible. In this experiment, the con南京工程学院毕业设计(论文)外文资料翻译原 文 题 目:A New Reconfigurable Logic for CNC Lathe Controllers原 文 来 源:Proceedings of the 2009 IEEE International Conference on Mechatronics and Automation 学 生 姓 名: 计千喻 学 号: 231120416 所在院(系)部: 工业中心 专 业 名 称: 机械设计及其自动化 一种新的可重构逻辑的数控车床控制器作者:Jingchuan Dong+, Yunfeng Wang*, Zijing Wang+ , Taiyong Wang+摘要:可重构器件已发展到在计算机上实现数字控制(CNC)系统。可重构器件提供CNC和灵活性的系统设计的高执行性能。然而,少数工作是在可重构逻辑数控车床中实现的。本文开发了数控车床螺纹中的同步运动和可重构逻辑的一个新的重采样算法。一个实验系统构建和测试结果验证所提出的架构。关键词:数控车床,可重构逻辑,重采样,车丝一引言计算机数控(CNC)机广泛应用于现代工业。作为该机的控制中心,CNC控制器会影响很多方面,如速度,精度和稳定性的机加工性能。在加工速度和精确度的快速增加,传统的基于软件的CNC控制器都难以满足的计算要求。可重配置硬件的引入解决了这个问题。可重构硬件有助于在许多方面的数控系统。首先,控制算法可以通过硬件具有高执行效能实施。设计者可以采取硬件的并行结构的优点,以加速的算法。此外,时间执行能力的硬件能够理想的实现有效控制。其次,可重配置硬件提供了设计者的灵活性。由于可重构硬件的可编程特性,设计者可以定制品种各界集成到一个单芯片容易和快速。第三,可重配置硬件提供修改或更新在先前版本的硬件设计的可能性。即使控制器已被交付给用户,硬件逻辑仍然可以修改,以满足新的要求。可重构硬件在运动中的研究最近已开发了控制系统。有些工作的重点位置控制器的设计,陈等人。实施使用分布式算法(DA)方案1现场可编程门阵列(FPGA)的PID控制算法,陶等人。一个三级位置前馈追加到硬件PID控制器2。赵等人。比较了多PID控制器的结构不同机械工程系通道控制3,王等人。设计了一种基于FPGA的神经网络PID控制器4。 苏等人。实现的FPGA芯片上的数字差分析器(DDA)的控制算法5。在数控控制器等功能也进行了研究。 Osornio-Rios的等。实现与数控和机器人应用6冲击限制了基于多项式的硬件配置文件生成器。尤曾家丽等人。在FPGA中实现实时的NURBS插补算法7。然而,缺乏对数控车床控制器,这是本文的重点实施可重构器件的工作。本文开发了数控车床螺纹中的同步运动和可重构逻辑的一个新的重采样算法。如下本文将结构;在第2节,一个数控控制器和车丝过程的体系结构将讨论;在第3节,重采样方法的原理将出台;在第4节,可重构逻辑的硬件设计进行说明;在第5,使用所提出的方法的数控车床控制器的示例将提交。2 背景A. CNC控制器体系结构数控控制器的体系结构示于图1所示。该架构包括四个控制层8:智能控制,运动控制,设备控制和物理设备。人机界面(HMI)与经营者进行交互,并调用智能控制层做加工工作。在智能控制层中,输入NC程序被解释为机器指令。机器指令是由运动控制层,它由内插器和一个离散事件控制模块的执行。内插器根据所需的运动指令和速度分布生成位置指令。其他指令,如工具选择和冷却剂控制,通过离散事件控制模块处理。设备控制层操作的物理设备来实现加工过程。它集成一个轴控制模块和离散输入/输出控制模块。在本文的研究中,在设备控制层是通过使用一个重新配置的设备中实现。Fig.1数控控制器的架构。对于数控车床,运动功能分为两类:正常的运动和主轴同步运动。正常运动在轮廓加工使用,而在主轴同步运动在车丝过程中使用。正常运动的原理类似于在一个铣床的运动,已成功地实现了对由其他研究人员可配置器件。本文着重对主轴同步运动的可重构硬件。B.螺纹,数控车床 维持螺纹精度,进给运动必须与主轴旋转同步,如图(1)中。 F是进给速度(mm/分),S是主轴转速(rpm)和L是螺纹(毫米)的引线。F = SXL(1)增量式旋转编码器安装于主轴以确定其角度。作为主轴旋转时,编码器产生的该偏移90度的相位彼此如图信号的两个通道(A和B)。 2.通过监控脉冲的数目和A的相对相位和B信道,无论是位置和旋转方向可跟踪。编码器还提供了一个索引信号,其中每转脉冲一次,作为角度位置的参考点。Fig.2旋转编码器的波形。图3示出在车丝过程9刀具路径的一个例子。当主轴旋转时,切割器移动到点1。然后,控制器等待索引信号来确定的所述主轴的所述绝对位置。一旦主轴旋转到所需的位置,车丝过程将开始与在进料方向上的加速度的移动。在加速,线程是不是精度。当加速度终止于点2,进料速度到达期望的速度和进给运动将与主轴同步。车丝过程结束之前,切割器将开始在点3减速的螺纹也是不减速时的精度。最后,该车丝过程停止在点4和刀具从工件移开。Fig.3 车丝过程的一个例子。主轴速度可以在车丝过程波动。根据(1),进料速度应该遵循主轴速度。车丝过程可能需要多个路程,以限制材料去除率或创建多个线程启动。刀具也可能改变在一个特殊的线程。因此,在车丝过程中,沿进给轴的运动必须与主轴的角位置同步。解决这个问题的传统方法可以被描述为以下步骤:1)在每个电机控制周期,采样主轴位置。2)用插补计算新的刀具线轮廓位置。3)更新各轴的指令位置。4)返回到步骤1,如果车丝过程没有完成。上述步骤必须在一个马达控制被执行每一次,因此所有的步骤必须以实时完成循环。然而,如果实时执行由软件执行时,控制算法的开销高,这是很难实现短的控制周期。此外,实时软件执行需要额外的处理器时间,以切换之间的真实时间任务和其他任务。中央处理器时间的比比长,任务的切换将非常大,周期相对较短。3. 重采样方法在我们的工作中,提出了重采样方法车丝时,为了避免内插算法的实时执行。此外,可重新配置的硬件被用于电动机控制等实时功能。 图4演示了重采样方法的原理:Fig.4 重采样方法原理1)内插器以恒定的速度假定主轴运行。因此,在每个周期中,主轴旋转是固定的。然后插入刀位置来确定螺纹齿形。由于不需要实际的插补器主轴位置,插补可以在电机控制周期前确定。2)在电动机控制循环中,通过重采样的位置曲线所生成的位置指令。该位置的曲线是用直线连接每个插位置重建。虽然主轴的角位置的增量可以改变,该命令位置可以通过重新采样来获得。主轴的位置由来自旋转编码器的脉冲计数测量。因此,在各电动机控制周期主轴位置的增量脉冲当量的整数倍。我们可以选择其中E是脉冲当量主轴编码器的并且是一个正整数。在两个连续的插值倍假设主轴定位Q)n和(PN+ X,和对于进给轴对应的内插位置是一个和An+1中,由于位置曲线由重建线性函数,在时间间隔内的位置的函数可以被写为作为主轴位置由编码器脉冲的计数表示的,在第(p(3)只能取离散值,让代(2)和(4)代入(3),我们得到等式(5)可以进一步写成增量形式等式(6)是用于重采样方法的算法。该算法涉及加法和除法。在计算中,如果AA是一个定点数和除法操作可以通过变速操作来实现。因此,重采样算法非常简单,它是适合于由硬件来实现。通过假设主轴以一定速度旋转时,相当于插补周期7可确定为如下其中P是每主轴的旋转产生脉冲的数目。从式(8),我们可以看到,插补周期是独立于电机控制周期。选择较大的N允许更长的等效插补周期,所以可以减少计算量。然而,大的N也可能会降低重采样精度。因此,计算成本和精度之间的平衡应该选择N.时要考虑四可重构逻辑许多的数控任务可以由硬件或由软件来实现。用可编程逻辑器件(PLD),如现场可编程门阵列(FPGA)和复杂的发展可编程逻辑器件(CPLD),越来越多的控制功能可以由硬件来实现。硬件的并行性质允许控制算法在实时运行。此外,PLD芯片的可重配置能力,提供了一个可以被开发和修改的快速灵活的硬件平台。A.可重构逻辑的体系结构在这项工作中的可重构逻辑设计的结构示于图5.结构由多个可重构模块。对于每一个进给轴,有一个轴缓冲器,重新采样器,指令位置多路复用器和马达控制器。为了简化设计,只有位置的增量被用于位置数据的传输。本方法避免了使用绝对位置,从而节省了在不同模块之间的数据交换的位线。每个轴包含位置数据的两个数据路径。数据路径是由命令位置复用器根据控制模式中选择。在正常模式中,重新采样器旁路和用于运动控制器的命令位置由轴缓冲器提供。在穿带模式中,重新采样施加位置曲线的采样。Fig.5可重构逻辑的结构轴缓冲保持在给定的内插器的下一个位置增量。因此,下一个内插的位置,可以从轴线缓冲器立即加载。然后,新的内插位置可以存储到缓冲一次。重新采样进行重采样算法。在两个通道的重新采样由采样控制模块控制。重采样控制器根据主轴位置控制重采样过程。运动控制器实现了位置控制算法,并提供接口向马达驱动器。几种控制算法可用,如数字微分分析器(DDA),PID和模糊控制器。在这项研究中,DDA控制器采用两个运动控制器通过从轴同步模块的控制信号同步。一些互补的模块也纳入PLD。主轴编码器适配器是接口主轴编码器。数字滤波器被集成在适配器以防止噪声的影响。离散I / O模块处理CNC控制器的通用输入和输出信号。中断控制模块用于当特定事件发生时,产生中断信号给CPU。该时钟控制模块提供时钟信号给其它模块。运动控制器和其他配套模块的硬件实现了文献中已全面讨论,本文的其余部分将在实现重采样算法的讨论。B.重采样逻辑结构 图6示出了重采样控制器的结构。从主轴编码器适配器的信号被用来确定主轴的位置。为了得到高的分辨率,输入脉冲频率翻了两番。加工开始前,相位被装载到相位偏移偏移寄存器及相位输出比较低。因此,与门的输出为低。当启动信号到达时,相位计数器将等待索引信号。索引信号的到来之后,相位计数器开始计数输入脉冲。当脉冲计数匹配相位偏移,相位输出比较意愿变高。的四倍编码器输入信号将经过与门作为时钟进行加法运算。重新采样将执行加(6)当ADD CLK信号到来。该ACLK计数器计数增加次A 比特计数器。它需要除了次溢出。当溢出发生时,在负荷信号设置和重采样将加载新的内插位置形成轴缓冲。Fig.6重采样控制器的结构。重新采样的结构示于图 7.包含一个移位器,一个加法器和三个寄存器。该移位器用来执行在(6)的除法运算。在这项工作中,我们选中N=5,输入A是由一个8位定点数来表示。重新采样器的输出是一个8位的定点数。Am是通过A的位移获得。当在负荷信号到来时,新的AM在REGO锁存 13位加法器使用做在(6)的加法运算。每次加入CLK信号谈到时间,REG1锁存相加的结果。如果电机控制器需要下一个命令的增量位置,OUT LOAD信号将变高。接着,再采样位置,I.S. REG1的高8位值,被锁定在REG2。该OUT LOAD信号也清除REG1的高8位。因此,在REG1的值是位置指令的增量。Fig.7 重新采样结构5. 实验验证数控车床控制器的建立是为了测试所提出的控制方法。实验数控系统的示意图示于图。 8.系统由两部分组成:非实时的部分和实时一个和非实时部分包括一个32位的ARM 920T微处理器,闪速存储器,SDRAM,通信端口和一个调试单元。非实时部运行Linux操作系统。控制软件包括用户界面,解释器,内插器,顺序逻辑,通信,NC文件管理等功能。实时部的硬件包括一个8位AVR微控制器,一个双端口RAM,一个FPGA芯片,一个D / A转换器和用于信号转换和隔离的电路。双端口RAM用于缓冲的实时控制命令,其中包括内插位置。 AVR的微处理器被用于获取控制命令,并将其发送到FPGA和主轴D /实时A转换器。可重新配置的控制逻辑是在FPGA上实现。在D / A转换器的主轴控制主轴速度。图9示出在CNC控制器的硬件设置。在实验系统,主轴编码器的分辨率为4800脉冲每转(后四人间)。电动机控制周期为1.02毫秒。一些加工程序都在该控制器上进行测试来检查建议的可重构逻辑。一个分析程序在正常模式下测试直线和圆弧饲料的功能,而其他三个方案验证在线程模式下的重采样算法。螺纹的参数在表I.在车丝测试列出,主轴转速被设定为500rpm下,实际速度是518.5转速486.4之间。根据(8),在测试的等效插补周期为0.8毫秒。 图10示出在测试中车丝过程。 图11表示成品零件。所有的测试程序和预期一样。结果表明,该架构是可行的数控车床控制器。Fig.8 实验系统的图Fig.9 控制器的硬件设置表一测试线程的参数参数测试一测试二测试三大径(mm)202216-22中径(mm)18.420.414.4-20.4长度(mm)303030铅(mm)1.531.5沥青(mm)1.51.51.5递减率000.2评论单头直螺纹双启动直螺纹单头锥螺纹Fig.10车丝过程Fig11.成品零件值得注意的是,通过利用可重构逻辑,电动机控制任务和重新采样算法,可以由硬件实现。可重配置硬件增强了数控系统的性能。而且,这种结构允许车丝之前要计算的内插点,从而消除了需要在实时运行插值。通过以间歇方式运行的内插,在实时上下文切换开销被降低,和一个更高的数据吞吐量是可能的。在这个实验中,控制软件是一个标准的Linux系统,这是一个非实时操作系统上运行。因此,开发人员可以使用标准的编程工具来构建数控系统软件。6. 结论本文介绍了可重构硬件体系结构的数控车床控制器的开发。我们提出了一个新的重采样算法数控车床的车丝过程。尽管主轴速度的波动此重新采样算法可以维持螺纹精度。通过利用重新采样算法,内插任务和电机控制任务可以异步运行。从而,内插可以在不久实时的方式来完成。这将简化软件设计和提供了更高的数据吞吐量。从设计者的观点,重新采样算法适用于由硬件执行。再采样逻辑的结构也被本文提出。重新采样,与其他的可重构逻辑结构一起,可以很容易地集成到一个可编程逻辑器件。可重构硬件的应用提高了系统的性能和系统设计提供了灵活性。实验已经成功验证了该重采样算法的可行性和相应的可重构逻辑。参考文献1 Y.F. 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