Rotation Control, Interlocking, and Self‐Positioning of Active Cogwheels

Abstract

Gears and cogwheels are elemental components of machines. They restrain degrees of freedom and channel power into a specified motion. Building and powering small‐scale cogwheels are key steps toward feasible micro and nanomachinery. Assembly, energy injection, and control are, however, a challenge at the microscale. In contrast with passive gears, whose function is to transmit torques from one to another, interlocking and untethered active gears have the potential to unveil dynamics and functions untapped by externally driven mechanisms. Here, it is shown the assembly and control of a family of self‐spinning cogwheels with varying teeth numbers and study the interlocking of multiple cogwheels. The teeth are formed by colloidal microswimmers that power the structure. The cogwheels are autonomous and active, showing persistent rotation. Leveraging the angular momentum of optical vortices, we control the direction of rotation of the cogwheels. The pairs of interlocking and active cogwheels that roll over each other in a random walk and have curvature‐dependent mobility are studied. This behavior is leveraged to self‐position parts and program microbots, demonstrating the ability to pick up, direct, and release a load. The work constitutes a step toward autonomous machinery with external control as well as (re)programmable microbots and matter.

Document Details

Document Type
Pub Defense Publication
Publication Date
Sep 10, 2022
Source ID
10.1002/aisy.202200129

Entities

People

  • Antoine Aubret
  • Jérémie Palacci
  • Quentin Martinet

Organizations

  • Army Research Office
  • University of California, San Diego

Tags

Readers

  • Robotics and Automation.
  • Systems Analysis and Design
  • Tribology (the study of the boundary interaction between sliding surfaces, lubrication, wear and friction).