124 Driving Performance of High Reduction Planetary Gear Drive with Arc Tooth Profile and Pin

Kanemasu

Itakura

et al. 2013

AMM

In this work, wear of reinforced poly-ether-ether-ketone (PEEK containing PTFE, graphite and carbon fibres) polymer bushes in friction against 7075 aluminium alloy cam plates is investigated in order to establish the application possibilities in transmission parts in humanoid robot joints. The PEEK bush surface conditions as well as the input axis-output axis transmission error (backlash) require close examination. Sliding wear tests were performed on bushes under 900 kgfcm loaded torque, while the cam plate oscillated. Based on the wear observation, it was found that PEEK wear fragments in the interface between PEEK bush and aluminium alloy cam plate formed a PEEK film.

Section: Introductionmentioning

confidence: 99%

Wear and Transmission Error between PEEK Bush and 7075 Aluminium Alloy Cam Plate Components in Robot Joints

Kanemasu

Itakura

et al. 2013

AMM

“…Control systems that are responsible for stable biped walk in large robots are subject to extensive research [1][2], however their accuracy has proven to be lower than expected. This is the motivation for the development of a newly, highly accurate joint with high torque capacity [3][4][5][6][7][8][9]. A prototype joint system presented in our previous work consists of a harmonic drive gearing device and a two-axes mechanism using a resin bush.…”

Section: Introductionmentioning

confidence: 99%

Observation of Wear Surface between Pure PEEK and Counterpart Materials; Titanium and 7075 Aluminum Alloy, in Robot Joint

Itakura

Kida

et al. 2013

AMM

In our recent work, in order to realize joint element in lightweight and compact joints for tall humanoid robots, a new joint element was designed. It consists of a harmonic drive gearing device, a multi axis mechanism and a resin bush. The resin bush slides on a titanium crankshaft of the pole shape while the joint works. However, the bush was stuck, and stopped movement of the joint. In our present work, we observed the bush surfaces against two materials; the titanium and the 7075 aluminum alloy have been used. We could observe the differences between the titanium and the 7075 aluminum alloy by an optical microscope after the fatigue tests.

“…The need for more and more sophisticated robots accomplished with high endurance, speed and accuracy, able to perform more and more complicated movements continues rising unceasingly in various fields such as medical assistance, life support, customer services etc. To satisfy this need by further improving robotic joint systems, lightweight components comprising independant pieces providing the system's ability to withstand high loads and a high accuracy backlash are necessary [1][2][3][4][5][6][7] .…”

Section: Introductionmentioning

confidence: 99%

Influence of Wear and Thermal Deformation on Machined PEEK Plastic Bush and Ti Crank Shaft

Polymers and Polymer Composites

Kida

Kanemasu

et al. 2012

In biped walking humanoid robot, toughness, durability and lightweight of joint parts are crucial factors due to parts’ constant exposure to high torque and loads. Such ergonomically challenging conditions create the need for joint systems comprising independent elements capable of keeping the component operable for long periods of time. In our work, we focused on wear and thermal deformation in two different grades of both poly-ether-ether-ketone (PEEK) and polyoxymethylene (POM) plastic bushes. The components used for investigation were bushes typically employed in speed reduction devices in joint models for biped walking humanoid robots. In such joint systems, plastic bushes are directly connected to a crankshaft, playing an important role in the robot's movement ability. In order to acquire the knowledge of how to build more efficient systems, the influence of the titanium crankshaft roughness on the frictional heat occurring between the shaft and the polymer bush as well as the input axis-output axis backlash require close examination. Based on Rolling Contact Fatigue test, we established the optimal machining conditions for the crank shafts and bushes. Also, superior to other tested polymers as far as glass transition temperature, wear toughness and thermal deformation are concerned, PEEK was found to be the best suiting material for our investigation.