TY - JOUR

T1 - Vitrimeric shape memory polymer-based fingertips for adaptive grasping

AU - Kashef Tabrizian, Seyedreza

AU - Alabiso, Walter

AU - Shaukat, Usman

AU - Terryn, Seppe

AU - Rossegger, Elisabeth

AU - Brancart, Joost

AU - Legrand, Julie

AU - Schlögl, Sandra

AU - Vanderborght, Bram

N1 - Publisher Copyright: Copyright © 2023 Kashef Tabrizian, Alabiso, Shaukat, Terryn, Rossegger, Brancart, Legrand, Schlögl and Vanderborght.

PY - 2023/7/12

Y1 - 2023/7/12

N2 - The variability in the shapes and sizes of objects presents a significant challenge for two-finger robotic grippers when it comes to manipulating them. Based on the chemistry of vitrimers (a new class of polymer materials that have dynamic covalent bonds, which allow them to reversibly change their mechanical properties under specific conditions), we present two designs as 3D-printed shape memory polymer-based shape-adaptive fingertips (SMP-SAF). The fingertips have two main properties needed for an effective grasping. First, the ability to adapt their shape to different objects. Second, exhibiting variable rigidity, to lock and retain this new shape without the need for any continuous external triggering system. Our two design strategies are: 1) A curved part, which is suitable for grasping delicate and fragile objects. In this mode and prior to gripping, the SMP-SAFs are straightened by the force of the parallel gripper and are adapted to the object by shape memory activation. 2) A straight part that takes on the form of the objects by contact force with them. This mode is better suited for gripping hard bodies and provides a more straightforward shape programming process. The SMP-SAFs can be programmed by heating them up above glass transition temperature (54°C) via Joule-effect of the integrated electrically conductive wire or by using a heat gun, followed by reshaping by the external forces (without human intervention), and subsequently fixing the new shape upon cooling. As the shape programming process is time-consuming, this technique suits adaptive sorting lines where the variety of objects is not changed from grasp to grasp, but from batch to batch.

AB - The variability in the shapes and sizes of objects presents a significant challenge for two-finger robotic grippers when it comes to manipulating them. Based on the chemistry of vitrimers (a new class of polymer materials that have dynamic covalent bonds, which allow them to reversibly change their mechanical properties under specific conditions), we present two designs as 3D-printed shape memory polymer-based shape-adaptive fingertips (SMP-SAF). The fingertips have two main properties needed for an effective grasping. First, the ability to adapt their shape to different objects. Second, exhibiting variable rigidity, to lock and retain this new shape without the need for any continuous external triggering system. Our two design strategies are: 1) A curved part, which is suitable for grasping delicate and fragile objects. In this mode and prior to gripping, the SMP-SAFs are straightened by the force of the parallel gripper and are adapted to the object by shape memory activation. 2) A straight part that takes on the form of the objects by contact force with them. This mode is better suited for gripping hard bodies and provides a more straightforward shape programming process. The SMP-SAFs can be programmed by heating them up above glass transition temperature (54°C) via Joule-effect of the integrated electrically conductive wire or by using a heat gun, followed by reshaping by the external forces (without human intervention), and subsequently fixing the new shape upon cooling. As the shape programming process is time-consuming, this technique suits adaptive sorting lines where the variety of objects is not changed from grasp to grasp, but from batch to batch.

KW - adaptive grasping

KW - additive manufacturing

KW - manipulation

KW - shape adaptive fingertip

KW - shape memory polymer

UR - http://www.scopus.com/inward/record.url?scp=85165966296&partnerID=8YFLogxK

U2 - 10.3389/frobt.2023.1206579

DO - 10.3389/frobt.2023.1206579

M3 - Article

AN - SCOPUS:85165966296

VL - 10.2023

JO - Frontiers in robotics and AI

JF - Frontiers in robotics and AI

SN - 2296-9144

M1 - 1206579

ER -