Ken Goldberg

UC Berkeley


The vibratory bowl feeder is the oldest and still most common approach to the automated feeding (orienting) of industrial parts. In this talk we consider a class of vibratory bowl filters that can be described by removing polygonal sections from the track; we refer to this class of filters as traps.

For an n-sided convex polygonal part and m-sided convex polygonal trap, I'll describe an O((n+m) log (n+m)) algorithm to decide if the part will be rejected by the trap, and an O((nm)^{2+e}) algorithm which deals with non-convex parts and traps. We then consider the problem of designing traps for a given part, and consider two rectilinear subclasses,   balconies and  gaps. I will describe linear and O(n^2) algorithms for designing feeders.

We are developing an online Java applet to demonstrate the design algorithms. I'll demonstrate and show video of physical experiments using a commercial inline vibratory feeder. We are not aware of any previous algorithms for the systematic design of vibratory bowl traps.

(This is joint work with R-P. Beretty, M. Overmars, and F. van der Stappen at U. Utrecht)

Ken Goldberg ( is Assoc. Professor of Engineering at UC Berkeley. He received his PhD in 1990 from the School of Computer Science at Carnegie Mellon University. Goldberg and his students study geometric algorithms for feeding, sorting, and fixturing industrial parts. He was named a National Science Foundation Young Investigator in 1994 and NSF Presidential Faculty Fellow in 1995. He is currently editing a book on Internet Telepistemology for MIT Press. For more information please see:

Edited by Leonidas Guibas