A statically balanced SCARA-like industrial manipulator with high energetic efficiency
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The purpose of the work is the improvement of the energetic efficiency of automated lines assisted by four-degree-of-freedom serial robots with three translations and one rotation about a vertical axis (Schoenflies motion).
A novel robotic architecture (BalArm) has been designed. It is derived from a RRPR SCARA by substituting a four-bar mechanism for the vertical prismatic joint, in order to balance statically the robot by means of a counter-weight or a torsional spring. The kinematic and dynamic models of the manipulator are described.
Using these models, different typical pick-and-place operations have been simulated; the results show that for low-speed motions the mass balancing is more efficient, while for high-speed motions the elastic balancing is preferable; the advantage threshold depends on the task trajectory, speed and acceleration and on the preload of the elastic element.
From a constructive point of view, the BalArm robot can be realized with modular solutions, in order to easily change the static balancing. This allows to adapt the balancing to the specific working cycle to minimise the energy consumption, with potential economical and environmental benefits.
KeywordsEnergetic efficiency Static balancing Industrial robotics
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- 7.Smith MR (1975) Optimal balancing of planar multi-bar linkages. In: Proc. of the 4th world congress on theory of machines and mechanisms, New-Castle-Upon-Tyne, pp 145–149 Google Scholar
- 9.Ulrich N, Kumar V (1991) Passive mechanical gravity compensation for robot manipulators. In: Proc. of the IEEE international conference on robotics and automation, Sacramento, pp 1536–1541 Google Scholar
- 10.Hervé JM Device for counter-balancing the forces due to gravity in a robot arm. United States Patent, 4,620,829, May 1986 Google Scholar
- 12.Gosselin CM, Wang J On the design of gravity-compensated six-degree-of-freedom parallel mechanisms. In: Proc. of IEEE international conference on robotics and automation, Leuven, Belgium 16–20 May, 1998, vol 3, pp 2287–2294 Google Scholar
- 13.Makino H, Furuya N (1980) Selective compliance assembly robot arm. In: Proc. of the first international conference on assembly automation, pp 77–86 Google Scholar
- 15.Bruzzone L, Bozzini G Energetic efficiency of a statically balanced hybrid industrial manipulator. In: Proc. 9th international workshop on research and education in mechatronics, REM 2008, September 18–19, 2008, Bergamo Google Scholar