Toward Gripper-Integrated Active Electrosense for Pre-Contact Sensing in Underwater Soft Grippers

2026-06-02

AI Summary

Underwater grasping often suffers from visual failure due to turbidity, glare, and self-occlusion of the gripper, lacking reliable pre-contact perception. This work proposes integrating lightweight active electrolocation into an octopus-inspired soft robotic gripper, introducing this modality for the first time as a complementary sensing approach to vision in soft underwater manipulation systems. By employing a discrete electrode arrangement and off-the-shelf hardware, multi-channel voltage signals are acquired under excitation voltages of 5–20 V across frequencies from 1 mHz to 1 kHz. Experiments demonstrate that conductive spherical objects elicit distinct and structured voltage responses, confirming the feasibility and effectiveness of this method for pre-contact underwater perception.

Abstract

Underwater manipulation often occurs under degraded visibility due to turbidity, glare, and gripper occlusion, limiting the reliability of vision-based perception during approach and grasping. In such settings, soft grippers are well suited for compliant interaction, but they typically lack an onboard pre-contact cue that can guide approach and closure when vision is unreliable. This extended abstract explores active electrosense as a lightweight sensing modality that can provide a proximity-like signal prior to contact by measuring perturbations of an applied electric field in conductive media. We instrument an octopus-inspired gripper with a discrete electrode layout and record multi-channel sensing voltages using off-the-shelf hardware. Simulation and tank experiments with a suspended conductive sphere show structured, object-dependent changes in the multi-electrode voltage readout relative to empty-water baselines, with detectability varying across excitation of 5 to 20 V and frequencies from 1 mHz to 1 kHz. These findings motivate systematic investigation of gripper-integrated electrosense as a complementary pre-contact cue for underwater soft manipulation.

Problem

• underwater manipulation
• soft grippers
• pre-contact sensing
• active electrosense
• vision degradation

Innovation

• active electrosense
• soft gripper
• pre-contact sensing
• underwater manipulation
• electrode array