PR2 Beta Sites: Spotlight on KU Leuven

Unified framework for task specification, control and coordination for mobile manipulation

Suppose you want a robot to assist you in carrying an object through a crowded environment. For this to work, the robot must know which item you want to pick up, how to pick it up and with what force, how to avoid both moving and non-moving obstacles, and where to set the object down. Furthermore, it must do all of these tasks while taking your movements into account.

Katholieke Universiteit Leuven has already developed a number of tools that will enable developers to make this a reality with the PR2. Their iTaSC (instantaneous Task Specification using Constraints) and skills framework will enable developers to specify this complex task of carrying an object and avoiding obstacles, all while tracking the human co-operator's movements. iTaSC allows developers to specify constraints for the motion and forces the robot uses, and it can take into account the many uncertainties such a task presents. Carrying an object also requires complex, real-time control over the robot's motors and sensors. KU Leuven's Real-Time Toolkit (RTT) for Orocos will enable developers to control multiple iTaSC motions together.

The PR2 will need to be able to track people and other moving obstacles. For this, a state-of-the-art multi-target tracking and localization algorithm (MTTL) will be added to ROS. The group will also integrate ROS with the OpenRobot simulator, which uses the open-source 3D content creation suite Blender.

KU Leuven's work on these tools will help create reusable, complex tasks for solving many other difficult challenges. The iTaSC framework has applications in robotic surgery, such as moving a surgical tool in precise laparoscopic surgery, as well as enabling robots to manipulate objects together while also taking into account the presence of people in the area.

Team PhotoThe Team

The KU Leuven team has both a mechanical and software engineering background. Its primary expertise relevant to the PR2 program is in specification and real-time control of complex tasks for robots with many degrees of freedom and multiple sensors.

Professors Herman Bruyninckx, co-founder of the Orocos open robot control software project, and Joris De Schutter, pioneer of the iTaSC framework, are leading the project. Dr. Ruben Smits, developer of the iTaSC and skills framework and experienced contributor to both Orocos and ROS, is the principal investigator.

The team also consists of post-doctoral researchers Tinne De Laet, Eric Demeester, and Peter Soetens, and PhD students Koen Buys, Wilm Decré, and Dominick Vanthienen, who are all active in the field of robotics at the Department of Mechanical Engineering, and who have already contributed substantially to the open source community.
 
The project futhermore benefits from strong collaborations with Professor Jan Swevers, Professor Luc De Raedt’s Machine Learning group at the Department of Computer Science, and with Professor Moritz Diehl from KU Leuven’s Center of Excellence in Optimization in Engineering (OPTEC).

Presentation

Below is a video of Koen Buys presenting KU Leuven's proposal to the rest of the PR2 Beta Program participants. You can download the slides as PDF.

Article written with assistance from Eric Demeester.