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We present a method for generating fast, torque-efficient motions in real-time. Given a dynamic model of a robot, we first obtain a reasonably large set of minimum torque motions for arbitrary starting and ending configurations, that also achieve minimum time without actuator saturation; these motions are obtained through a Lie group dynamics-based optimization procedure previously developed by the...
This paper presents a novel approach to plan an optimal joint trajectory for a manipulator robot performing a compliant motion task. In general, a two-step scheme are deployed to find the optimal robot joint curve. Firstly, we approximate the functional and use Newton's iteration to numerically calculate the joint trajectory's intermediate discretized points, instead of solving a corresponding nonlinear,...
Estimating the configuration is one of the key issues for successful mobile robot navigation. Dead-reckoning is simple and fast but it can lead to inaccurate or unreliable estimates. Range sensors are widely used in known environment for localization, but it may not always work due to sensor range limit. Optical flow sensor such as the optical mouse gives accurate relative movement but it requires...
In the present work, it is described a fast motion-planner for mobile robots moving on natural terrains. The planner is very flexible: it can be use on a wide class of vehicles with different kinematics, and with generic shapes (even with concavity and holes). Because of these characteristics, it could be applied for the assembly planning in the manufacturing industry, as in the piano mover's problems...
The MUSES-C mission is the world's first sample and return attempt to/from the near Earth asteroid. In deep space, it is hard to navigate, guide, and control a spacecraft on a real-time basis remotely from the earth mainly due to the communication delay. So autonomy is required for final approach and landing on an unknown body. It is important to navigate and guide a spacecraft to the landing point...
In this paper, we show the simulation result to find the suitable fish swimming modes (specially BCF swimming) for fish like underwater robot system. To find the suitable swimming modes, we assume that they have the same length, volume, and weight, but the different numbers of actuator (joint). And we use the minimum number of the joint for each swimming mode. We derive the dynamic equation for each...
Navigation of autonomous underwater vehicles (A.U.V.) in very shallow waters implies acoustic detection. In single beam sonar systems, sound emitted by ultrasonic transducers is diffracted and secondary lobes appear. Considering the sea bottom's backscattering properties, secondary lobes can be used to work out the three-dimensional equation of the plane that represents the seabed. In this paper,...
In order to enhance dexterity in execution of robot tasks, a redundant number of degrees-of-freedom (DOF) is adopted for design of robotic mechanisms like robot arms and multi-fingered robot hands. Associated with such redundancy in DOFs relative to the number of physical variables necessary and sufficient for description of a given task, an extra performance index is introduced for controlling such...
Automatic control of a mobile robot with nonholonomic constraints normally depends on complex signal processing mechanisms, e.g. predictive control. This paper presents a new trajectory tracking method for a mobile robot by combining predictive control and fuzzy control. To overcome the time delay caused by the slow response of the sensor, the algorithm employs predictive control to predict the position...
In this paper, casting and winding dynamics of hyper-flexible manipulator is analyzed. Casting and winding with hyper-flexible elements like strings, ropes or wires should be a useful operation to capture a distant target object A multi-link system connected by passive non-elastic joints is employed as a discrete dynamic model of hyper-flexible systems. Casting and winding dynamics is analyzed with...
Small robots can be beneficial to important applications such as civilian search and rescue and military surveillance, but their limited resources constrain their functionality and performance. To address this, a reconfigurable technique based on field-programmable gate arrays (FPGAs) may be applied, which has the potential for greater functionality and higher performance, but with smaller volume...
The research described in this paper addresses the problem of automatic execution of robotic tasks, considering uncertain environment. The focus on the paper is on the mathematical methodology used to address this problem, which belongs to the family of optimum systems control methods. The main mathematical definitions and the methodology background are given and a hybrid system model of a compliant...
We present a new sensor-based robot motion planning framework for mobile robot navigation in unknown environments. The main idea of the proposed planning approach, inspired by our recent works on using harmonic function-based probabilistic roadmaps (HFPRM) for robotic navigation in known environments (model-based cases) (Kazemi et al., 2004, 2005), is to utilize a fluid dynamic (FD) paradigm based...
A novel approach for configuration space obstacle(C-obstacle) construction and collision detection of manipulators by precompiling the global topology of a robot's free space is proposed in this paper. The approach consists of an off-line phase plus an on-line phase. In the off-line phase, a C-obstacle database (COD) for a given robot is setup in which the C-obstacle bitmaps are stored and indexed...
In this paper, an approach is proposed to determine real-time an optimized and collision-free path for a fixed wing flying vehicle moving in a dynamically changing 3D space. In the algorithm, boundary conditions, kinematic constraints, and collision avoidance criteria are explicitly considered and satisfied by a family of trajectories parameterized in terms of three polynomials along the primary axes...
The work illustrated in this paper concerns a new technique for resolving the problem of path planning in a static environment; this technique is called flat potential field. This new approach combines the simplicity of application of exact cell decomposition with the efficiency of local algorithms such as the potential field. The paper describes, in detail the phases that make up the algorithm, and...
The paper describes an experimental activity concerning the mechanical characterization of soft fingertips for robotic hands, focusing on the effects of the presence of an inner rigid core, as in robotic fingers with an endo-skeletal articulated frame covered by an external layer of soft material. By means of a purposely-designed test equipment, fingertips with differently sized cores have been tested,...
In this paper we present a new approach to simulate deformable linear objects (DLOs) for use in a haptic feedback system. Our goal is to optimize efficient computation and preciseness. The presented approach is inspired from the well known method of "finite elements", but avoids a exact physical model
This paper deals with use of manipulators and robots in the process of decommissioning of A-1 nuclear power plant in Jaslovske Bohunice, Slovak Republic. It describes current situation of the first stage of A-1 decommissioning and shortly lists advanced technologies used during this process. It describes in more detail the manipulators MT-15, MT-80, MT-80A, DENAR-41 and remotely controlled tool carrier,...
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