Critically fast pick-and-place with suction cups

TL;DR

This paper introduces a novel, fast, and computationally efficient pipeline for pick-and-place tasks using suction cups, ensuring contact stability and optimizing movement speed, validated on a physical robot system.

Contribution

It presents a new contact stability model, a stability constraint identification procedure, and a time-optimal path parameterization pipeline for suction-based pick-and-place tasks.

Findings

Cycle time for pick-and-place tasks was less than 5 seconds.

The pipeline was successfully validated on a physical robot system.

The full pipeline is released as open-source.

Abstract

Fast robotics pick-and-place with suction cups is a crucial component in the current development of automation in logistics (factory lines, e-commerce, etc.). By "critically fast" we mean the fastest possible movement for transporting an object such that it does not slip or fall from the suction cup. The main difficulties are: (i) handling the contact between the suction cup and the object, which fundamentally involves kinodynamic constraints; and (ii) doing so at a low computational cost, typically a few hundreds of milliseconds. To address these difficulties, we propose (a) a model for suction cup contacts, (b) a procedure to identify the contact stability constraint based on that model, and (c) a pipeline to parameterize, in a time-optimal manner, arbitrary geometric paths under the identified contact stability constraint. We experimentally validate the proposed pipeline on a physical robot system: the cycle time for a typical pick-and-place task was less than 5 seconds, planning and execution times included. The full pipeline is released as open-source for the robotics community.