Mobile robots for professional industrial cleaning

29 August 2014

Will the cleaning robot be as much a natural part of professional industrial cleaning as a sweeper or a steam cleaner soon? The Federal Ministry of Economy and Technology (BMWi) in Germany wants to explore how robot-supported cleaning can be implemented during the course of its joint 'Plug & Play for automated systems' (AutoPnP) project.

This project is led by Fraunhofer IPA in Stuttgart, in cooperation with Dussmann Service, an expert facilities management company. The project is utilising the standardised lightweight arm, a gripper hand and an electric quick-change module from SCHUNK, the competence leader for clamping technology and gripping systems.

Up to 70% of the cost incurred in professional industrial cleaning is related to cleaning floors and waste disposal. In order to automate this work, scientists at the Fraunhofer IPA evolved the robot assistant 'Care-O-bot® 3', and programmed the necessary software functions with the aim that this mobile robot could also be used for cleaning business premises.

It autonomously moves through the offices and inspects the floor surfaces. Soiling is automatically detected, mapped and cleaned with a cordless electric broom. If the attempt fails, since a dried coffee strain cannot be removed with a broom, the robot marks the position of the soiling on its map. It then informs the cleaning personnel. Moreover, the robot can recognize wastepaper baskets, inspect their fill level and empty the contents of full wastepaper baskets into a collection bin. A powerful SCHUNK Powerball lightweight arm and a multi-purpose SCHUNK SDH2 3-finger hand are used for handling the wastepaper baskets. The system also positions the cleaning trolley for the necessary task and the required freedom of movement.

Modular software and hardware

The SCHUNK lightweight arm is specifically designed for such mobile applications. The robust arms are designed for relatively high payloads and due to the 24V technology, they are fully mobile. In daily operations, the system is very economical. For example, the energy previously required for a 100W bulb is enough for the operation of a complete SCHUNK lightweight arm. Its lightweight, highly rigid design increases energy efficiency. In the case of mobile applications, it pays off in terms of extended run-times. At a repeat accuracy of +/-0.1mm, the lightweight arm offers the optimum pre-requisites for precise handling. Since the drive amplifiers and controllers are directly integrated in the modules, they don’t need a separate cabinet.

In order to be able to operate with maximum flexibility, SCHUNK has developed an electric quick-change module for this project. This puts the robot into the position to add-on other tools instead of the gripper hand. A typical example would be a cordless electric broom for cleaning the carpet.

Utilising a quick-change module with integrated bus system (CAN), the gripper hand, the cordless electric broom or other tools can be centrally controlled by the robot. In order to ensure that the cleaning robot really meets the requirements of commercial use, the project is being executed in close cooperation with the cleaning specialist Dussmann Service of Berlin. A modular software structure that integrates hardware and software components can ensure that the solution is suitable for further adaptation in the field of application.