Measurement of Backlash and Fatigue Wear of PEEK Bush in Robot Joint under Middle Load

Abstract

In order to establish the application possibilities in transmission parts in humanoid robot joints, wear of reinforced poly-ether-ether-ketone (PEEK) polymer bushes in friction against 7075 aluminium alloy cam plates is investigated. Additionally the transmission error (backlash) in robot joint was measured. The PEEK bush wear requires close examination as well as the input axis-output axis transmission error. Fatigue wear tests were performed on bushes under middle load at 3000 rpm motor speeds, while the cam plate oscillated in the humanoid robot leg joint evaluation system under 1300 kgfcm (132 Nm) load torque. The robot joint using PEEK bush achieved stable small backlash due to good friction perforance.