iTaSC as a unified framework for task specification, control, and coordination, demonstrated on the PR2

This paper describes the implementation of the instantaneous Task Specification using Constraints (iTaSC)Skill on a PR2. The framework allows easy specification and code-generation for robot tasks. Its power will be demonstrated by a mobile co-manipulation task of a human and a PR2 robot. The PR2 has to follow the instructions of the human and help him carrying an object, while avoiding obstacles and unnatural poses. Although the framework and its implementation are demonstrated on a PR2, it can be used for any robotic system. The software, including the demonstration is publicly available under an open-source license. Robots have evolved from simple six degree-of-freedom industrial robots in a cage, to mobile platforms with redundant arms and multiple sensors, for example the PR2. These mobile platforms have escaped from their cages to a domestic, cluttered and populated environment. The resulting increase in complexity and uncertainty shows the need for a highly modular methodology for motion and task specification and coordination. This paper demonstrates the capabilities of such a highly modular methodology, applied on the PR2. The demonstration includes a mobile co-manipulation task of a human and a PR2 robot, in which they handle an object together trough a cluttered and populated environment. The PR2 should follow the instructions of the human and assist him carrying the object, while avoiding obstacles. Figure 1 shows an artist’s impression of the co-manipulation task.