OCTOBER 19-20, 2012 - YMCA University of Science & Technology

Proceedings of the National Conference on
Trends and Advances in Mechanical Engineering,
YMCA University of Science & Technology, Faridabad, Haryana, Oct 19-20, 2012
DESIGN AND OPTIMISATION OF ROBOTIC GRIPPER: A REVIEW
Vaibhav Raghav 1 , Jitender Kumar 2 and Shailesh S.Senger 3
1,2,3 M.Tech. Department of Mechanical Engineering, YMCAUST, Faridabad
Abstract
In this paper, the field of robotic gripper and the work in this area over the last two decades has been reviewed.
In the recent past many different robot grippers have been developed to grasp one or a few specific objects.
Those grippers are well suited for continuous work in structured environments. On the other hand, some
researchers have focused their attention on sophisticated general purpose grippers having kinematics and
dextrousness similar to the human hand. With the evolution of automation in industries, grasping become an
important topic in robotics research community.The paperemphasis on study of current existing robotic grippers,
their basic design and optimization of the same.
Keywords: Robotic gripper, Design, Flexibility, Optimization parameters.
1. INTRODUCTION
A gripper is the mechanical interface between the robot and its environment. Without it, the robot cannot perform
the pick-and-place functions .In industrial applications it is common to handle objects with different geometries
and weights. Variety of robotic grippers are developed highly flexible and multi functioned.
Particularly humanoid robotic technology attracts high attention of researchers. The highly dynamic and highly
accelerated gripper model can be easily set at intermediate positions by regulating the pressure. Pneumatic
grippers are very easy to handle and are generally cost-effective because air hoses, valves and other pneumatic
devices are easy to maintain.
Since a gripper gives a great contribution to practical success of using an automated and/or robotized solution, a
proper design may be of fundamental importance[6].
A proper gripper design can simplify the overall robot system assembly. It also increases the overall system
reliability and decreases the cost of implementing the system[5]. Thus, the design of the gripping system is very
important for the successful operation.
It is not possible literally to apply all the guidelines to a specific set of design. As one guideline may suggest one
design direction while another may suggest the opposite.
So the most suitable technique is to examine each particular station and then coming to a conclusion which
favours the more relevant guidelines.
The design guidelines may be as follows [4]:-
1) Gripper weight should be minimized. This favors the robot to accelerate more quickly
2) Grasping of objects should be secure: This allows the robot to run at higher speeds in zig-zag profile thereby
reducing the cycle time.
3) Grip multiple objects with a single gripper. It helps to avoid tool changes hereby reduce idle time.
4) Completely encompass the object with the gripper: This is to help hold the component securely.
5) Grasp the object without deformation: the object are easily deformed and so care should be taken during
grasping these objects.
6) Minimize finger length: The longer the fingers of the gripper the more they are going to deflect during
grasping an object.
7) Design for proper gripper-object interaction: If, however, a flat surface is being used, then a high friction
interface is desired since the part would not be aligned anyway and the higher friction increases the security
of the grasp.
8) Flexibility: The ability of a gripper to conform to parts that have irregular shapes and to adapt to parts that is
inaccurately oriented with respect to the gripper.
The ideal gripper design should be synthesized from independent solutions to the three considerations shown in
Figure 1. Grippers essentially replace the human hand. If the gripping abilities of a mechanical five-fingered
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