Catálogo de publicaciones - libros

This paper presents a kinematic and force analysis of a mobile robot built on the principle of parallel mechanisms. The robot consists of an upper plate connected to 3 legs, each equipped with an asynchronous driving unit. A kinematic model for the robot provides data for accurate position estimate, even in rough and slippery terrains where conventional odometry fails. The paper presents an analysis of the forces acting on the robot under various surface conditions and robot configurations. This analysis provides useful data to determine whether a specific motion can be completed given the limitations on stability, the geometry and friction of the surface, and the required motion direction. The paper presents simulation results that are verified by experiments using our prototype model.

In this paper, we propose a collision avoidance algorithm for two nonholonomic tracked mobile robots transporting a single object based on a function-allocation concept. In this algorithm, a leader robot is controlled manually. A follower robot estimates the desired trajectory of the leader along its own heading direction and generates the motion for transporting the object and for avoiding obstacles by using an omni-directional vision sensor. We experimentally implement the proposed algorithm in a tracked mobile robots system, and illustrate the validity of the proposed control algorithm.

Dynamic stability is an important issue for vehicles which move heavy loads, turn at speed, or operate on sloped terrain. In many cases, vehicles face more than one of these challenges simultaneously. This paper presents a methodology for deriving proximity to tipover for autonomous field robots, which must be productive, effective, and self reliant under such challenging circumstances. The technique is based on explicit modeling of mass articulations and determining the motion of the center of gravity, as well as the attitude, in an optimal estimation framework. Inertial sensing, articulation sensing, and terrain relative motion sensing are employed. The implementation of the approach on a commercial industrial lift truck is presented.

In this paper, design and integration of ROBHAZ-DT2 is presented which is a newly developed mobile manipulator system. It is designed to carry out military and civilian missions in various hazardous environments. In developing the integrated ROBHAZ-DT2 system, we have focused on two issues: 1) novel mechanism design for mobility and manipulation and 2) intuitive user interface for teleoperation. In mechanism design, a double tracks connected by a passive joint has been designed to achieve high speed and rugged mobility on uneven terrain. In addition, a six-dof foldable manipulator suitable for the mobile manipulation has been designed. Secondly, a new compact 6-dof haptic device has been developed for teleoperation of the ROBHAZ-DT2. This haptic device is specially designed for simultaneous control both of the mobile base and the manipulator of ROBHAZ-DT2. As a result of integration of RobhAZ-DT2 and the user interface unit including the haptic device, we could successfully demonstrate a typical EOD task requiring abilities of mobility and manipulation in outdoor environment.

This paper introduces the Autonomous Vehicle Project (AVP) at the ANU together with a discussion and an example of driver assistance systems. A set of necessary core competencies of such a system is identified and in particular a system for force-feedback in the steering wheel when departuring from a lane is presented. A system like this is likely to reduce accidents due to driver fatigue since unintentional lane changes become more difficult. The presented system utilises a robust lane tracker which is experimentally evaluated for the purpose of driver assistance.

In the paper we consider skilled tasks that are performed by a human-like robot in outdoor unstructured environment when working interactively with a human operator. As skilled tasks we understand tasks, which – like when humans perform them – are non-trivial and demand learning or training. Typically such tasks may also fail and require several trials to be successfully executed. Performing requires use of senses and development of a unique miniplan, which takes into account the present situation. The mini-plan, which may also be called “skill”, produces a sequence of unit operations needed for successful performing of the task. The paper discusses preliminary experiences on implementing and experimenting such skilled tasks with a mobile centaur-like service robot.

To evaluate a neural interface, which comprises integral microelectrodes for neural recording or stimulation used for the control of human prosthetic devices, such as artificial limbs, a proto-type artificial body is being prepared for implantation of the interface in a rat. As a result of the first trial, new linkage mechanisms were developed, and a robot equipped with the mechanism was able to perform various walks likes an animal, including sidestep at high speed by swinging its legs.

This paper presents methods for cooperative mapping of partially or totally unknown area with human and robotic explorers. Mapping is supported with online modelling of presence, which will create a common understanding of the environment for both humans and robots. The studied key methods are human navigation without ready installed beacons, human and robotic SLAM, cooperative localization and cooperative map/model building for common presence. Methods are developed, tested and integrated in a European Community research project called PeLoTe.

Human care and service demands an innovative robotic solution to make easier the everyday of elderly and disabled people in home and workplace environments. The EU project MATS has been developing a new concept of climbing robot for this type of service applications. The robot developed by University Carlos III of Madrid is a 5 DOF selfcontaining manipulator, that includes on-board all the control system. The main advantage of the robot is its light weight, about 11 kg for a 1.3 m reach. The robot is a symmetrical arm able to move between different points (Docking Stations) of the rooms and, if it is necessary, “jump” to (or from) the environment to the wheelchair. In this way the MATS robot should became a home companion and assistance for numerous persons.

We describe a mobile robot system, designed to assist residents of an retirement facility. This system is being developed to respond to an aging population and a predicted shortage of nursing professionals. In this paper, we discuss the task of finding and escorting people from place to place in the facility, a task containing uncertainty throughout the problem.

Planning algorithms that model uncertainty well such as Partially Observable Markov Decision Processes (POMDPs) do not scale tractably to real world problems such as the health care domain. We demonstrate an algorithm for representing real world POMDP problems compactly, which allows us to find good policies in reasonable amounts of time. We show that our algorithm is able to find moving people in close to optimal time, where the optimal policy starts with knowledge of the person’s location.