Christopher Armbrust

{RAVON} -- The Robust Autonomous Vehicle for Off-road Navigation

Abstract: This chapter describes the work of the Robotics Research Lab at the University of Kaiserslautern in the field of autonomous off-road robotics. It introduces concepts developed for hazard detection, terrain classification, and collision-free autonomous navigation. As an example of a system implementing the described techniques, the mobile off-road robot RAVON is presented. Experiments have been carried out to prove the effectiveness of the approaches.

Off-road Robotics—An Overview

This article gives an overview of the current state of research in the field of off-road robotics. It focuses on techniques used in the areas of perception, environment representation, as well as navigation, and introduces different types of robot control systems. A presentation of different applications is given along with an outlook on future developments.

Methodology for robot mapping and navigation in assisted living environments

Robust navigation in living environments demands high requirements on the control system of a robot. Due to typically narrow passages between obstacles, precise navigation is required. To achieve accuracy in navigation, detailed representation of the environment around the robot needs to be developed. Robust and precise mapping of the environment helps in overcoming the dynamics in the living environment like movement of furniture and human beings. Prompt recovery from unreachable paths while navigating is also an essential component of the living environment robots. This paper describes a behaviour-based navigation system in assisted living environments. The navigation system uses a grid map created from data obtained from laser scanner and ultrasonic sensors mounted on a small sized robot, ARTOS. ARTOS is specially designed for indoor living environments able to navigate through narrow corridors and closely placed furniture in the living environment.

The ICARUS project - Command, Control and Intelligence (C2I)

This paper describes the features and concepts behind the Command, Control and Intelligence (C2I) system under development in the ICARUS project, which aims at improving crisis management with the use of unmanned search and rescue robotic appliances embedded and integrated into existing infrastructures. A beneficial C2I system should assist the search and rescue process by enhancing first responder situational awareness, decision making and crisis handling by designing intuitive user interfaces that convey detailed and extensive information about the crisis and its evolution. The different components of C2I, their architectural and functional aspects are described along with the robot platform used for development and field testing.

Mobile Robot Navigation Support in Living Environments

Navigation and application functionality of mobile robots rely on their collision-avoiding capabilities, also known as local navigation. We present the mobile robot ARTOS (Autonomous Robot for Transport and Service) that is particularly designed to operate in living environments and therefore faces the problem of fuzzy and unstructured obstacles. The local navigation architecture is motivated regarding decisions on sensor hardware setup as well as the software layers that support and influence navigation control.

Verification of behaviour networks using finite-state automata

This paper addresses the problem of verifying properties of behaviour-based systems used for controlling robots. A behaviour-based system typically consists of many interconnected components, the behaviours, which in combination realise the systems overall functionality. The connections between the behaviours are crucial for the correct operation of a system. Therefore, key properties of behaviour-based systems are verifiable based on their behaviour interconnections. In this paper, it is described how behaviour-based networks can be (automatically) modelled using finite-state machines and how model checking with the Uppaal toolbox can then be applied for verification and analysis tasks.

Formal Verification of Behaviour Networks Including Hardware Failures

The paper deals with the problem of verifying a behaviour-based control system. Although failures in sensor hardware and software can have strong influences on the robot reaction, they are often neglected in the verification process. Instead, perfect sensing is assumed. Therefore, this paper provides an approach for modelling the sensor chain in a formal way and connect it to the formal model of the control system. This model can be verified using model checking techniques, which is shown on the example of the control system of the autonomous off-road robot ravon (ravon: Robust Autonomous Vehicle for Off-road Navigation).

Tool-assisted verification of behaviour networks

This paper deals with the problem of assisting developers when verifying properties of complex behaviour-based systems. A central aspect of behaviour-based systems is the interaction between the behaviours, as a lot of the functionality of a system typically arises from this interaction. Hence, verification has to deal with the specialities of behaviour interaction. Previous work has introduced a concept for modelling behaviour-based systems as networks of finite-state automata and for applying model checking as verification technique. As the manual verification of large networks is tedious and errorprone, the work at hand introduces a concept for assisting developers by partly automating the verification process. The applicability of the presented approach is demonstrated using the behaviour-based control system of an autonomous bucket excavator.

A Behaviour-Based Integration of Fully Autonomous, Semi-Autonomous, and Tele-Operated Control Modes for an Off-Road Robot

Abstract This paper describes a concept for a behaviour-based integration of tele-operator commands into the control system of a mobile robot. The control system presented features different control modes which allow for pure teleoperation, assisted teleoperation, and fully autonomous navigation. It is explained how the tele-operator can influence the robots motion at any time and how he can simply and continuously change the degree of his influence.

Using an autonomous robot to maintain privacy in assistive environments

In our societies, the number of senior citizens living on their own is increasing steadily. The lack of permanent attention results in the late detection of emergency situations. Labour-intensive care is already a high burden for the society; therefore, it seems reasonable to promote technology that helps to detect and react in case of emergency situations that elderly people may encounter. In the last decade, assistive environments have been established by integrating surveillance devices into the living environments giving remote operators access to monitor the senior inhabitant at home for detecting emergency situations. However, due to poor privacy in terms of intrusion into the private life of an elderly person, there will be an unfavourably low acceptance of such systems. This paper introduces a two-stage strategy and proposes to replace a possibly large number of human-controlled monitoring devices by a single autonomous mobile system. The first stage will be performed by the autonomous system to detect an emergency situation. The human operator will be obligatory only at the final stage when the system assumes that an emergency has occurred and the final evaluation of the situation is required. The self-assessment will reduce the human factor related to privacy issues. Copyright