Harmonic functions are solutions to Laplace's equation. Such functions
can be used to advantage for potential-field path planning because th
ey do not exhibit spurious local minima. Harmonic functions are shown
here to have a number of properties that are essential to robotics app
lications. Paths derived from harmonic functions are generally smooth.
Harmonic functions also offer a complete path-planning algorithm. We
show how a harmonic function can be used as the basis for a reactive a
dmittance control. Such schemes allow incremental updating of the envi
ronment model. Methods for computing harmonic functions respond well t
o sensed changes in the environment, and can be used for control while
the environment model is being updated. (C) 1993 John Wiley & Sons, I
nc.