The authors describe a novel modular design and a VLSI implementation of a bit-serial pipelined fast Fourier transform (FFT) coprocessor. The proposed architecture is based on a distributed hardwired control mechanism. The control of various subunits in the processor is done by local controllers and the synchronization of operations is provided by a global controller. This FFT processor is a custom-built chip which has a built-in self-test (BIST) capability. BIST is provided using a coprocessor to a microprocessor, and the data transfer is controlled by asynchronous signals. A prototype of the proposed processor was implemented in 3- mu m SCMOS technology; it can operate at a maximum frequency of 50 MHz. The chip is a 32-pin square package, and it has a total area of 2.2 cm/sup 2/.>

The development and validation of a sensor-driven control model for multijointed cooperating robotic arms is explored. The approach is used to explore an anthropomorphic model, and to then reason by analogy to discover a robust control model for robotic arm motion. This approach uses human-like joint motion profiles and sensory information of all joints, evaluates the weighted work done by each joint in cooperative motion, and then synthesizes a minimal effort motion trajectory to precisely and efficiently position the robotic arm end effector. This sensor-based approach significantly reduces the computational requirements for such cooperative motion. The result is a less complex, faster, and adaptive control process. A pressure-servoed hydraulic motion system has been developed to implement the movement strategy. This is a major step toward a long-term research goal of conceptualizing in an intelligent way to implement a manufacturing task.>