Engineers at the University of California San Diego, inspired by the unspooling of measuring tape, are suggesting that measuring tape-like material could be used in the making of a robotic gripper.
The team proposes that such measuring tape-enhanced grippers would be ideal for agricultural applications because their extremities are soft enough to handle fragile fruits and vegetables.
Source: David Baillot/University of California San Diego
The proposed robot, dubbed GRIP-tape, which stands, in part, for grasping and rolling in-plane, reportedly solves a problem common among the current iteration of robotic grippers, which tend to be bulky so as to accommodate the additional mechanisms to enable gripping appendages to expand.
To eliminate the bulkiness of such designs, the researchers developed a flexible gripper that can both be stored in a small container when retracted and that can reach far when extended. To accomplish this, the researchers bound two tapes together with adhesive.
Specifically, the gripper features two "fingers," composed of two spools, each of which is comprised of two rolls of measuring tape bound together. The team noted that each spool is rolled up into a compact configuration, with just a small piece extending outward in a triangle shape to create a so-called finger. These “fingers” are powered by four motors that each control the finger's motion.
With each finger capable of moving independently, the triangle pieces can extend and lengthen to capture far away objects. Likewise, the fingers can also retract, bringing those objects in its grasp closer to the robot arm that the gripper is mounted on.
Making measuring tape appropriate for such an application is that it is both springy — enabling users to bend it and return it to its original state — and durable, thanks to its steel construction. Further, it is thin enough that it won't damage objects in its grasp.
Additionally, the gripper uses the entire length of the tape as a gripping surface. And it can also move to rotate objects of different shapes and stiffnesses or function as a conveyor belt, depositing objects it grasps into containers.
During trials, the gripper easily lifted large fruits like fresh lemons.
The GRIP-Tape is detailed in the article, “Grasping and Rolling In-plane Manipulation Using Deployable Tape spring Appendages,” which appears in the journal Science Advances.
