A General Contact Force Analysis of an Under-Actuated Finger in Robot Hand Grasping

Abstract

This paper develops a mathematical analysis of contact forces for the under-actuated finger in a general underactuated robotic hand during grasping. The concept of under-actuation in robotic grasping with fewer actuators than degrees of freedom (DOF), through the use of springs and mechanical limits, allows the hand to adjust itself to an irregularly shaped object without complex control strategies and sensors. Here the main concern is the contact forces, which are important elements in grasping tasks, based on the proposed mathematical analysis of their distributions of the n-DOF under-actuated finger. The simulation results, along with the 3-DOF finger from the ADAMS model, show the effectiveness of the mathematical analysis method, while comparing them with the measured results. The system can find magnitudes of the contact forces at the contact positions between the phalanges and the object.

Underactuated robotics: A review

“…62 Gao et al 15 proposed a 3-RRS (R represents a rotating pair and S stands for spherical side) parallel mechanism based on the generation of underactuated parallel joints that is shown in Figure 9. Ha et al 63 developed a mathematical analysis model of contact forces for the underactuated finger in a general UR hand during grasping. By using springs and mechanical constraints, the underactuated concept in robotic grip allows the hand to adjust itself to an irregularly shaped object without complex control strategies and sensors and with actuators less than DOFs.…”

A Systematic Approach to Stable Grasping of a Two-Finger Robotic Hand Activated by Jamming of Granular Media

“…Others adopted flexible fingers, fingers with flexible surfaces as an interface for grasping, or fingers with flexible joints [4][5][6][7][8][9][10]. Moreover, under-actuated mechanisms have also been employed to achieve safe and stable grasping [11][12][13][14][15][16][17][18]. While these approaches have proved effective, the levels of control and accuracy are still far from the biomimicry of natural grasping.…”

Effect of Object Size and Location on Contact Forces and Grasping Stability for an Underactuated Robotic Manipulator

“…Many researchers have studied underactuated manipulators as related to: Their design and analysis; Rea (2011;Yao and Ceccarelli, 2011;Nacy and Nayif, 2016;Birglen and Gosselin, 2005): Their optimization; Birglen and Gosselin (2004;Nacy et al, 2009): Their usage as grippers or robotic hands; Birglen et al (2008;Kragten, 2011;Laliberté and Gosselin, 2003;Zhao and Zhang, 2010;Meijneke et al, 2011;Dandash et al, 2011;Jung and Oh, 2013;Azlan and Hiroshi, 2010;Laliberte et al, 2002): Their mechanism types; Carrozza et al (2004;Yang et al, 2004;Cabas et al, 2006;Krut, 2005;Dechev et al, 2001): Their grasping stability analysis; Kim et al (2010;Zhang et al, 2009;Rizk et al, 2007;Ha et al, 2016;Kragten and Herder, 2007;Luo et al, 2004;Kragten et al, 2011).…”