---
publication_id: "OT-2026-000002908"
title: "Collapsible protrusions having a variable coefficient of friction"
published_at: "2026-09-15T19:16:05.197529Z"
canonical_url: "https://opentechnical.org/p/OT-2026-000002908"
categories:
  - "robotics-automation/robot-architectures"
keywords:
  - "b25j9/1612"
  - "b25j9/1612"
  - "b25j9/1612"
  - "b25j13/08"
  - "b25j13/081"
  - "b25j13/081"
---

# Collapsible protrusions having a variable coefficient of friction

## Abstract

A plurality of collapsible protrusions extending from a base including a first end, a second end, a first surface, and an outer surface. The second end is opposite the first end. The first surface is distal from the base. The outer surface is between the first end and the second end. The outer surface has a variable coefficient of friction. The variable coefficient of friction increases in a direction towards the base. The second end has a coefficient of friction greater than the coefficient of friction at the first end.