The old detachable hand technique...

Here is a robotic technology straight from hell, er, I mean the Swiss Federal Institute of Technology in Lausanne, Switzerland (EPFL). It is a robotic arm that can shoot off it's hand in order to complete sinister, er I mean, useful tasks around the castle. I'll refer to this phenomenon as, Thing Mode...

This work was presented as Beyond Manual Dexterity: Designing a Multi-fingered Robotic Hand for Grasping and Crawling at the IEEE International Conference on Robotics and Automation (ICRA) 2024 by Xiao Gao, an EPFL researcher. As with many IEEE journals, this paper is probably doomed to the oblivion of papers over the paywall, but luckily they have shared a video on Gao's YouTube channel as a message in a bottle.

The video is an interesting watch, despite the complexification of the task and solution. The general idea is, if the object you want to grasp is outside of your workspace, you can deploy your hand to retrieve it. They get a bit hand wavy about using a genetic algorithm to design the optimal placement of fingers on the autonomous hand, which ended up being four close together and one offset, so like a human hand. I think this configuration was probably chosen to resemble a hand, not because it is optimal for walking and grasping. Fingers evolved for grasping and manipulation, not for walking. Technically, any number of leg-fingers can achieve a walking gait. And maybe they used their genetic algorithm software to learn the central pattern generator (CPG) timings needed to achieve better walking efficiency.

There is also discussion in the video of using the fingers to grasp multiple objects on opposite sides of the hand, but yeah, everyone is pretty familiar with using their fingers to grasp several objects on one side. I'm not sure about the advisability of a design intended to grasp on both sides because you will trade off efficiency on both sides.

It's also a bit hand-wavy that they don't use the typical biological solution of moving the body and arm closer to the object to grasp. Though in the end, it is pretty cool to deploy part of the robot body to achieve a task in a domain the original robot is not suited for. Kind of like a go go robotic hand situation.

The full video is embedded in the References section below.

References

• IEEE ICRA 2024
• EPFL Robotics