Paper Info
Title
Hitting the sweet spot: Automatic optimization of energy transfer during tool-held hits.
Abstract
Tool-held hitting tasks, like hammering a nail or striking a ball with a bat, require humans, and robots, to purposely collide and transfer momentum from their limbs to the environment. Due to the vibrational dynamics, every tool has a location where a hit is most efficient results in minimal tool vibrations, and consequently maximum energy transfer to the environment. In sports, this location is often referred to as the “sweet spot” of a bat, or racquet. Our recent neuroscience study suggests that humans optimize hits by using the jerk and torque felt at their hand. Motivated by this result, in this work we first analyze the vibrational dynamics of an end-effector-held bat to understand the signature projected by a sweet spot on the jerk and torque sensed at the end-effector. We then use this analysis to develop a controller for a robotic “baseball hitter”. The controller enables the robot-hitter to iteratively adjust its swing trajectory to ensure that the contact with the ball occurs at the sweet spot of the bat. We tested the controller on the DLR LWR III manipulator with three different bats. Like a human, our robot hitter is able to optimize the energy transfer, specifically maximize the ball velocity, during hits, by using its end effector position and torque sensors, and without any prior knowledge of the shape, size or material of the held bat.
Year
DOI
Venue
2017
10.1109/ICRA.2017.7989185
ICRA
Field
DocType
Volume
Control theory,Torque,Simulation,Control theory,Jerk,Control engineering,Robot end effector,Engineering,Vibration,Robot,Trajectory,Swing
Conference
2017
Issue
Citations 
PageRank 
1
0
0.34
References 
Authors
9
5
Name
Order
Citations
PageRank
Jörn Vogel1116.48
naohiro takemura200.68
Hannes Hoppner3123.83
Patrick van der Smagt418824.23
Ganesh Gowrishankar501.35