Virtual Rapid Robot Prototyping

Competition in marketplace requires manufacturers to develop their products in shorter turn-around times. This encourages engineers and researchers to devise methodologies to respond to this market-driven requirement. Rapid prototyping is one solution to produce a design in minimum amount of time. In this paper we focus on rapid prototyping of robots. For this purpose, development of the robot design starts with a computer-aided design (CAD) model, system assembly, and simulation of the system motion. It then progresses to the development of kinematic and dynamic model simulations, and is completed by designing a controller for the robot. This streamlined approach allows easy reiteration of the design process at any stage; thus, it allows the designer to optimize system parameters as much as possible. The rapid prototyping environment presented in this work is developed by integrating the use of SolidWorks, Matlab and a number of their modules, and demonstrated on an RP manipulator. Although the process is applicable to the design of any mechanical system, robots with their high degrees of freedom are especially suitable for rapid prototyping. INTRODUCTION Computer aided design (CAD) software is a tool to design any physical system either in twoor in threedimensional space in a virtual environment. This tool is especially useful for designers in the design of multidegree-of-freedom (DOF) robots to test the performance of the robots even before manufacturing them. As professional software packages evolve, more functions are made available to the design engineers. However, to design a robotic system, usually several software tools are needed. This work addresses the integration of two software packages; SolidWorks and Matlab, to design robotic systems. SolidWorks is a powerful CAD tool to design system parts and assemblies, and animate the system motion utilizing its animation tool CosmosMotion. For certain types of parallel mechanisms, the software performs its own analysis while the robot is in motion to calculate various physical quantities of the system such as the forces exerted on joints, positions, velocities, accelerations, and so on. In this work, the capability of the software is extended to robots that use serial architectures by carrying out the kinematic analysis of the robot externally and then importing the data to SolidWorks for animation purposes. There are other kinematics solution packages that can be used in mechanism design and one example is SAM software [8]. Another helpful function of the software is also addressed by transferring the robot’s data into the Matlab Virtual Reality environment as VRML files. This enables the designer to also design the robot’s controller using the CAD files in addition to the structural design of the robot. The present work aims to demonstrate the integrated use of these software packages on parallel as well as serial robot systems. Matlab introduces the Simulink environment and Simmechanics blocks which can accomplish forward kinematics and dynamics modeling. Control algorithm of the robot can also be developed in this environment. Matlab recently released a new translator to translate SolidWorks model information into Matlab as Simmechanics blocks [4]. The blocks created are briefly explained in this paper. Final sections of the paper are dedicated to describe the integration of Virtual Reality model with Simmechanics model. Robot prototyping examples utilizing SolidWorks and Matlab are also provided. SOLIDWORKS MODELING AND ANIMATION Today’s CAD tools cannot be considered simple software tools for twoor three-dimensional sketching anymore since their capabilities allow them to be utilized as analyzers as well. Finite element analysis is probably the most-commonly used tool of many analysis tools that are available with these CAD tools. In this paper, we focus on mechanism design, its animation, and eventually its kinematic and dynamic simulations with the intent to develop a controller for the designed system. To accomplish this goal, the initial aim is to develop a robot using one specific CAD tool; SolidWorks, develop the joints and then actuate them in the CAD environment. Although most of the CAD tools have mechanism design and animation capabilities, each of them has