ModelSim/Simulink Cosimulation and FPGA Realization of a Multiaxis Motion Controller

Abstract

This paper is to implement a multiaxis servo controller and a motion trajectory planning within one chip. At first, SoPC (system on a programmable chip) technology which is composed of an Altera FPGA (field programmable gate arrays) chip and an embedded soft-core Nios II processor is taken as the development of a multiaxis motion control IC. The multiaxis motion control IC has two modules. The first module is Nios II processor which realizes the motion trajectory planning by software. It includes the step, circular, window, star, and helical motion trajectory. The second module presents a function of the multiaxis position/speed/current controller IP (intellectual property) by hardware. And VHDL (VHSIC Hardware Description Language) is applied to describe the multiaxis servo controller behavior. Before the FPGA realization, a cosimulation work by ModelSim/Simulink is applied to test the VHDL code. Then, this IP combined by Nios II processor will be downloaded to FPGA. Therefore, a fully digital multiaxis motion controller can be realized by a single FPGA chip. Finally, to verify the effectiveness and correctness of the proposed multiaxis motion control IP, a three-axis motion platform (XYZ table) is constructed and some experimental results are presented.

Design and Simulation of IIC based on FPGA

“…ModelSim is a kind of simulation software for digital circuit design. Developed by Mentor Graphics, it is designed for FPGA design provides efficient simulation and verification tools [9].…”

Development of A Linear Delta Robot with Three Horizontal-Axial Pneumatic Actuators for 3-DOF Trajectory Tracking

“…Equations ( 24) and (25) identify the singularities at which z = 0 or q 1 = q 2 = q 3 = r. There is no singularity at z = 0, because it implies that the moving platform is on the fixed base. Additionally, the initial length r of the moving platform is set to 60mm so the singularity q 1 = q 2 = q 3 = r possibly occurs when the three input actuated joint variables q 1 , q 2 and q 3 reach a distance of 60mm at the same time.…”

“…The helical circular motion trajectory is shown in Figure 14. The trajectory is formulated as [25]: ( ) z t are the increment of the angle, the increment of the z-axis, the radius, the x-axis position, the y-axis position, and the z-axis position of the moving platform, respectively. The helical circular tracking motion has a trajectory that is described by Equation (36), where the radius 10 , cm  …”