DYNAMIC ANALYSIS OF A COMPOSITE-MATERIAL FLEXIBLE ROBOT ARM

Increased demands for higher productivity and improved quality of good s have required industrial robots to operate at high speed with greate r precision. To meet these demands, robots should be lightweight, quic k, and accurate. In this study these requirements are satisfied by inc lusion of structural flexibility in the dynamic model of the robotic m anipulator and implementation of advanced composite materials in the s tructural design. The focus of this study is a three-dimensional, revo lute, composite-material robot arm. A displacement finite element dyna mic model is employed which includes all the coupling terms between th e rigid and flexible motions and takes into consideration the axial, i n-plane, and out-of-plane transverse deflections. The material damping of the laminated flexible link in both transverse directions is consi dered. The digital simulation results clearly demonstrate the advantag e of incorporating advanced composite materials in the structural desi gn of robotic manipulators. The effect of flexible motion on the rigid body motion is proven to be very important. It is also shown that the re is a significant difference between the behavior of the geometrical ly linear and nonlinear models. Effects of fiber orientation and mater ial orthotropy on the bending stress and displacements are also assess ed. It is demonstrated that the inclusion of material damping in the d ynamic model is an important factor in the design of flexible robot ar ms made of advanced composite materials.