Robotic manipulator real-time collision avoidance is a safety critical mode of teleoperation where motion commands which would result in a collision are disallowed. To achieve real-time performance, it is necessary to efficiently detect impending collisions between the manipulator and the workspace obstacles. A collision detection method is presented which is based upon two representations. The dynamic elements, such as the manipulator links, are modelled as sets of spheres. The static elements, such as the workspace obstacles, are represented as a weighted voxel map, in which the value of any voxel is indicative of its distance to the nearest obstacle. Combining these two representations results in a collision detection method which is obstacle count independent, i.e. independent of the number of obstacles in the workspace. This property is desirable for operation in cluttered environments with many obstacles, where the total number of calculations in the alternative collision detection paradigm of pairwise comparison will prohibit real-time performance. The method is efficient enough to satisfy a hard real-time constraint Novel algorithms are described to generate the voxel map and spherical model representations, and an implementation is described which uses the collision detection method for real-time teleoperated collision avoidance and online path planning of a Puma 560 manipulator.

A system for removing hidden edges in line displays of three dimensional scenes is described. The hardware system is relatively low cost, and operates on several hundred vectors in real-time. The system consists of a graphics peripheral connected to a PDP 11/55 computer and a software package to drive the peripheral.

A significant increase in the capability for controlling motion dynamics in key frame animation is achieved through skeleton control. This technique allows an animator to develop a complex motion sequence by animating a stick figure representation of an image. This control sequence is then used to drive an image sequence through the same movement. The simplicity of the stick figure image encourages a high level of interaction during the design stage. Its compatibility with the basic key frame animation technique permits skeleton control to be applied selectively to only those components of a composite image sequence that require enhancement.

article Computer animation of free form images Share on Authors: N. Burtnyk National Research Council of Canada, Ottawa, Ontario National Research Council of Canada, Ottawa, OntarioView Profile , M. Wein National Research Council of Canada, Ottawa, Ontario National Research Council of Canada, Ottawa, OntarioView Profile Authors Info & Claims ACM SIGGRAPH Computer GraphicsVolume 9Issue 1Spring 1975 pp 78–80https://doi.org/10.1145/964963.563743Online:01 April 1975Publication History 15citation620DownloadsMetricsTotal Citations15Total Downloads620Last 12 Months9Last 6 weeks0 Get Citation AlertsNew Citation Alert added!This alert has been successfully added and will be sent to:You will be notified whenever a record that you have chosen has been cited.To manage your alert preferences, click on the button below.Manage my AlertsNew Citation Alert!Please log in to your account Save to BinderSave to BinderCreate a New BinderNameCancelCreateExport CitationPublisher SiteGet Access