A hierarchical navigation system which delivers paths with continuous curvature for rectangularly-modeled vehicles is proposed. After a brief overview of the transport system consisting of omni wheel drive carriers, a...
详细信息
A hierarchical navigation system which delivers paths with continuous curvature for rectangularly-modeled vehicles is proposed. After a brief overview of the transport system consisting of omni wheel drive carriers, and on-carrier and off-carrier sensor components, the navigation module of this system is described. The multilevel navigation is based on a new polygonal partitioning of the Cartesian free-space, which allows a fast local modification of the partitions if obstacles are added or deleted. An A*-algorithm whose weight function is automatically adjusted by information on lower system levels delivers a coarse route through the environment (driving channel). Subsequently, a sequence of straight lines is generated, which are oriented along the right border of this channel. On the next level of path planning, curves are fitted into the corners of the line segment sequences to generate paths with continuous curvature. The generated, right-oriented paths are collision-free for rectangular modeled vehicles.< >
This paper presents a universal test data generator for the systematic evaluation of inverse kinematics systems. A Denavit-Hartenberg parameter based kinematics description language LDL has been developed; it is used ...
详细信息
This paper presents a universal test data generator for the systematic evaluation of inverse kinematics systems. A Denavit-Hartenberg parameter based kinematics description language LDL has been developed; it is used as input language for the generator. LDL allows the expression of kinematic and geometric constraints, which have to be satisfied by the resulting generated kinematics. Moreover, it is possible to generate certain well-known classes of manipulators. Combining the basic features and different kinds of constraints, a LDL program can be used to define and to generate classes of manipulators.< >
The integration of a three-dimensional sensor into a robot workcell is described. The sensor is based on the well-known coded light approach (CLA). The CCD camera of the CLA is mounted at the robot's hand and one ...
详细信息
The integration of a three-dimensional sensor into a robot workcell is described. The sensor is based on the well-known coded light approach (CLA). The CCD camera of the CLA is mounted at the robot's hand and one or more projectors are fixed outside the robot's work space. The principle of the CLA and the calibration of th robot-sensor-system are explained. An application in which the tool of the robot follows an unknown path on an arbitrary surface is presented. For evaluation reasons the deviation from the surface coordinates are simultaneously measured by a gage, allowing a quantitative error analysis.< >
It is known that the solution of the inverse kinematics problem for robot arms is mathematically very elaborate. A technique is proposed for automatically generating the closed-form inverse kinematics solution for mos...
详细信息
It is known that the solution of the inverse kinematics problem for robot arms is mathematically very elaborate. A technique is proposed for automatically generating the closed-form inverse kinematics solution for most industrial robots very efficiently. This is achieved by a careful structural analysis of equations resulting from systems like A/sub i-1//sup -1/ A/sub i-2//sup -1/. . . A/sub 1//sup -1R/T/sub H/=A/sub i/A/sub i+1/. . . A/sub n/ with (i=1, . . ., n), where A/sub i/ and /sup R/T/sub H/ denote the homogeneous transformation matrices between the adjacent robot links and the homogeneous robot hand-base transformation, respectively. Features derived from these equations are described, and it is shown how they can be used advantageously to solve the inverse kinematics problem symbolically. The system is implemented in Prolog and needs a few seconds on a PC for a complete inversion.< >
暂无评论