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Analog VLSI circuits for sensorimotor feedback


DeWeerth, Stephen P. (1991) Analog VLSI circuits for sensorimotor feedback. Dissertation (Ph.D.), California Institute of Technology. doi:10.7907/vvye-b883.


This thesis presents a design framework and circuit implementations for integrating sensory and motor processing onto very large-scale integrated (VLSI) chips. The designs consist of analog circuits that are composed of bipolar and subthreshold MOS transistors. The primary emphasis in this work is the transformation from the spatially-encoded representation found in sensory images to a scalar representation that is useful for controlling motor systems.

The thesis begins with a discussion of the aggregation of sensory signals and the resulting extraction of high-level features from sensory images. An integrated circuit that computes the centroid of a visual image is presented. A theoretical analysis of the function of this circuit in stimulus localization and a detailed error analysis are also presented. Next, the control of motors using pulse trains is discussed. Pulse-generating circuits for use in bidirectional motor control and the implementation of traditional control schemes are presented. A method for analyzing the operation of these controllers is also discussed. Finally, a framework for the combination of sensory aggregation and pulse-encoded outputs is presented. The need for signal normalization and circuits to perform this task are discussed. Two complete sensorimotor feedback systems are presented.

Item Type:Thesis (Dissertation (Ph.D.))
Degree Grantor:California Institute of Technology
Division:Engineering and Applied Science
Major Option:Computation and Neural Systems
Thesis Availability:Public (worldwide access)
Research Advisor(s):
  • Mead, Carver
Thesis Committee:
  • Mead, Carver (chair)
  • Barr, Alan H.
  • Culick, Fred E. C.
  • Bower, James M.
  • Burdick, Joel Wakeman
  • Abu-Mostafa, Yaser S.
Defense Date:27 May 1991
Record Number:CaltechETD:etd-06212007-074949
Persistent URL:
Default Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:2672
Deposited By: Imported from ETD-db
Deposited On:16 Jul 2007
Last Modified:16 Apr 2021 22:10

Thesis Files

PDF (DeWeerth_sp_1991.pdf) - Final Version
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