Resumo em Inglês:

This paper addresses trajectory planning in dynamic workspaces, for a robot subject to dynamic constraints and moving in a dynamic workspace. The case of a car-like robot A with bounded velocity and acceleration, moving in a dynamic two-dimensional workspace is considered. The solution proposed is an extension of the path-velocity decomposition that addresses motion planning in two complementary stages: (a) planning a geometric path and (b) planning the velocity along this path. Path-velocity decomposition is a practical way to address trajectory planning in dynamic workspaces since it decomposes the original problem into two more simple sub-problems. However, it presents a serious drawback: it cannot find a solution if a moving obstacle stops right on the computed path. A possible answers to this problem were to consider a set of candidate paths. The answer proposed in this paper makes use of the novel concept of adjacent paths. (like adjacent lanes of the roadway). A set of adjacent paths, one of which leads A to its goal, are computed. Then, assuming that A is able to freely shift from one path to an adjacent one, the motion of A along and between these paths is determined so as to avoid the moving obstacles while respecting 's dynamic constraints. The fact that it is possible to switch several times between two adjacent paths makes this approach more flexible and more powerful than one considering candidate paths.

Resumo em Inglês:

Abstract This paper deals with trajectory planning and motion learning for a redundant manipulator. Recently, behavior engineering for robotic systems has been discussed as a new technological discipline. A robotic system requires the whole structure of intelligence, and acquires skill and knowledge through interaction with a dynamic environment. Consequently, the whole structure determines the potentiality of intelligence. This paper proposes a robotic system with structured intelligence. Based on perceptual information, a robot with structured intelligence makes decision and action from four levels in parallel. In addition, the robot generates its motion through interaction with the environment, and at the same time, gradually acquires its skill based on the generated motion. To acquire skill and motion, the robot requires internal and external evaluations at least. This paper applies a virus-evolutionary genetic algorithm for trajectory planning and applies neural network for motion learning. Furthermore, we discuss its effectiveness through computer simulation results.

Resumo em Inglês:

This paper identifies attributes of intelligent robotic applications and surveys the different flavor in robot control architectures. Directions in robot control are discussed and the attributes and properties of different proposals are classified and compared. In the conclusion we present our point of view about the current state of designing robot control architectures.

Resumo em Inglês:

An approach based on concurrent object oriented programming (COOP) to build a control system for a mobile robot is presented. A behavior-based control system is decomposed in intercommunicating concurrent objects named Agents. These agents belong to five categories: Primitive Sensor, Virtual Sensor, Behavior, Primitive Actuator and Virtual Actuator. Based on this approach, a C++ tool is developed, where the categories above are implemented as C++ classes, in which built-in communication mechanisms are included. Each class has a standard interface and functionality. It is possible, then, to develop a complex control system by deriving new classes from the base classes and by instantiating objects. These objects are interconnected in a dynamic manner and thus building a control system with different behavior levels, which is able to react to environment changes.

Resumo em Inglês:

This paper proposes an algorithm for the scrollic (synchronously closing with rolling constraints) gripper based on active sensing about the displacement of its joints, in order to control the trajectory of objects grasped outside the workspace. The gripper has fingers composed of two cylinders in parallel, the translation and rotation of which are independently driven. This characteristic gives a dynamic decoupled behavior to the gripper, and makes it compliant to open during a close motion, or to rotate against the actuated direction, when forced by the inwards movement of the object. The algorithm presents a high level of tolerance concerning uncertainties about the object's position, weight and shape. The kinematics, design concept and control algorithm of the gripper are discussed in detail.

Resumo em Inglês:

We propose a multi-agent vision-based architecture to solve complex sensor-based planning tasks. A test bed implementation, with skills such as vision and collision avoidance, was used to run experiments in the proposed architecture. We demonstrate experimentally how the system can execute successfully complex assembly plans while dealing with unpredictable events and imprecise information, with no significant cost in run-time efficiency. Such experiments provided important insights about vision and planning and on how to build real world robotic systems.

Resumo em Inglês:

A comparative evaluation of two methods for visual tracking by saccade control of an active vision head with antropomorphic characteristics conducted at the ITA/INPE Active Computer Vision and Perception Laboratory is presented. The first method accomplishes fixation by detecting motion and controlling gaze direction based on gray-level segmentation. The second method aligns images of different viewpoints in order to apply static camera motion detection. Morphological opening is then employed to compensate for image alignment errors. Results from experiments in a controlled environment show that both approaches are capable of dealing with non-rigid forms and scenes with limited dynamics by operating at about 1 Hz. However, the comparative evaluation shows that image alignment improves tracking robustness to variations in lighting conditions and background texture. The results so far obtained encourage further applications in autonomous robotics and vision-aided robotic rotorcraft navigation.

Resumo em Inglês:

There exists an immense potential for the utilization of robotic airships as low speed, low altitude aerial vehicles in exploration, monitoring, and transportation tasks. This article discusses Project AURORA - Autonomous Unmanned Remote mOnitoring Robotic Airship which focuses on the development of the control, navigation, sensing, and inference technologies required for substantially autonomous robotic airships. Our target application areas include the use of robotic airships for environmental, biodiversity, and climate research and monitoring. Based on typical mission requirements, we present arguments that favor airships over airplanes and helicopters as the ideal platforms for such missions. We outline the overall system architecture of the AURORA robotic airship, discuss its main subsystems, and mention the research and development issues involved.