Tele-operated service robots for household and care

Abstract

Purpose: Service robots are a relatively new branch of robotics after the successful industry robots and the experimental humanoids. Service robots are supposed to perform tasks that normally are done by humans in particular daily life activities. However they do not have to do it in the same way as humans and neither do they not have to look like a human. Service robots have to operate in environments meant for humans so they have to navigate in environments with unforeseen moving objects and subjects, to mention only one of the challenges. This paper is based on our experience with a tele-operated service robot, named Rose. Tele-operated means that Rose is not completely autonomous but that it is remotely controlled by a human operator. The human operator has the option to control the robot manually or provide indications to carry out complex coordinated procedures (eg. move and grab object). Tele-operated service robots have a wide range of applications, such as in the building industry to carry and place heavy objects, or in the security business. We focused on daily life household tasks. Experiments with Rose were performed in a field lab setting, for the care of elderly people. They need attention several times a day, but in total not more than two hours. This means that one operator can service several homes. This results in a five-fold productivity improvement of care takers. After an introduction on tele-operated service robots, we concisely present the system design of Rose. Then we sketch the field lab experiments and we consider the lessons learned. Based on this information we present some scenarios for the future of tele-operated service robots for caretaking and household tasks. Both the technical and the application aspects will be covered. Method First, a number of general purpose use cases covering daily household activities such as warming a meal, picking and placing objects, turning on the light etc. were defined. From these use cases, the system architecture of Rose was derived using a construction technique called correctness by construction. This construction technique guarantees deadlock freedom and livelock freedom. The software development was carried out using the popular Robot Operating System (ROS) framework. Four rounds of tests covering all use cases were carried out by nurses from a care organization called Zuid Zorg in Waalre, the Netherlands. In the first three sessions the cockpit was located in a room next to the robot. In the fourth session, the cockpit was located in Veldhoven, another nearby town, while the robot remained in Waalre. Results from each test round were used to improve the software of Rose. Results & Discussion: From the results of all test sessions we were able to confirm feasibility in real-life scenarios and increased productivity by an operator while servicing multiple homes. Furthermore, consistency in performance can be achieved by exploiting the robots autonomy. Keywords: Correctness by construction; Home-care; Service robots