A new architecture for robot control

In this paper we discuss the demanding computational needs of robot control and describe a new computer architecture optimized for such problems. Inverse kinematics and dynamics for 6 degrees of freedom arms are often used as benchmarks to measure controller speed. According to current estimates, the new processor we describe can compute both of these problems, using 32 bit fixed-point operations, in less than 250 microseconds. This is an order of magnitude faster than existing state-of-the-art systems. Such benchmarks only measure a smallportion of the true robot control problem. The issues of interpolation, input/output, and multiple axis synchronization must also be addressed. As robotics becomes more advanced, the need for more compatationally intensive control algorithms (hybrid position/force control, sensory-based control, multiple robot cooperation, etc.) will grow. These now computationally-intractable problems must ultimately be computed in real-time. In this paper, we discuss current progress on a flexible (i.e. programmable) system which is fast enough to approach such problems. The system is targetted to support up to 40 synchronized axes, performing advanced control algorithms with an update rate over 1 KHz.

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