140-1 Sunday, Jan. 8 13:30 - 13:45 Elephant Trunk Forms Joints to Better Grip Objects WU, J*; HA, S; KIM, G; DHANUSHA , S; BRACCINI, S; HU, D; Gatech, Atlanta; Gatech, Atlanta; Gatech, Atlanta; Gatech, Atlanta; Zoo Atlanta, Atlanta; Gatech, Atlanta firstname.lastname@example.org
The boneless elephant trunk is the elephant's most versatile appendage, enabling it to grab objects as heavy as a log or as a small as a peanut. We measure the contact force that elephants apply to piles of vegetables as they squeeze them into a pile and pick them up. We find that elephants can be surprisingly gentle. Specifically, they push down on objects with only 5 percent of their trunk weight, less than half the weight that blindfolded humans apply to objects. This ability is made possible by the elephant forming joints with its trunk. The joint separates the trunk into two sections, the latter of which pushes down on objects purely with its self-weight. Elephants change the location of the joint accordingly to modify the downward force necessary to gather the food particles together. This work may inspire ways to control soft robotic actuators.