Peg–hole disassembly using active compliance

Abstract

When considered in two-dimensional space, a cylindrical peg being withdrawn from a clearance-fit hole can exhibit one of four contact states: no contact, one-point contact, two-point contact and line contact. Jamming and wedging can occur during the two-point contact. Effective control of the two-point contact region can significantly reduce resistance in peg–hole disassembly. In this paper, we explore generic peg–hole disassembly processes with compliance and identify the effects of key parameters including the degree of compliance, the location of the compliance centre and initial position errors. A quasi-static analysis of peg–hole disassembly has been performed to obtain the boundary conditions of the two-point contact region. The effects of key variables on the two-point contact region have been simulated. Finally, peg–hole disassemblies with different locations of compliance centre achieved using active compliance have been experimentally investigated. The proposed theoretical model can be implemented to predict the range and position of the two-point contact region from the perspective of peg–hole disassembly.

Electro-mechano responsive elastomers with self-tuneable conductivity and stiffness

“…Such a device could help a robotic manipulator to compensate for positional errors through its deformation, thereby preventing damage to tools or workpieces in tasks involving uncertain operational environments and complex contact scenarios. This is key to robotic manipulation requiring a high-level dexterity where motions and positions must be compensated on multiple axes 44,45 . However, state-of-the-art devices cannot provide adjustable stiffness and therefore have limited compensation ability.…”

An experimental human-robot collaborative disassembly cell

“…In addition, HRC disassembly can decrease reconfiguration time for different kinds of products. Our previous research showed that disassembly is not the simple reverse of assembly and requires different techniques for operations such as removing bearings from shafts (Zhang et al, 2019) and unfastening screws ( Li et al, 2020).…”

Industry 4.0 and Prospects of Circular Economy: A Survey of Robotic Assembly and Disassembly

“…The degree, location and initial error related to the compliance considerably affect the resulting performance. A quasi-static analysis of the foregoing factors, as well as the range, position and boundary conditions of the two-point contact region has been reported in [79].…”

“…Schematic illustration of a peg being withdrawn from a hole in a disassembly process, involving (a) Zero, (b) One, (c) Two or (d) Infinite contacting points between them, the latter constituting a line. The figure has been taken from [79].…”