Page 210 - Robots Androids and Animatrons : 12 Incredible Projects You Can Build

Suppliers
Aluminum bars, machine screws, tubing, and compression
springs are available in most well-stocked hardware stores.
Servo motors may be purchased at hobby shops or electronic
distributors.
Electronic components may be purchased from Radio Shack,
Images Company, Jameco Electronics, or JDR Electronics.
PIC microcontroller and front drive wheel may be purchased
at Images Company.
Images Company
39 Seneca Loop
Staten Island, NY 10314
(718) 698-8305
Jameco
1355 Shoreway Rd.
Belmont, CA 94002
(650) 592-8097

JDR
1850 South 10 St. 189
San Jose, CA 95112
(800) 538-5005

Building an intelligent photovore robot

Let’s see if we can create what may appear as intelligent behavior
in a photovore robot. In Chap. 6 we programmed a photoresistive
light tracking system. The tracking system locked onto a light
source and tracked it. When we placed the same tracking system
on a copy of Walter’s tortoise robot, it directed the robot toward a
light source. This steering behavior can be considered the first
stimulus-response layer.
The program illustrates how the rule-based microcontrollers can
simulate neural functions. For the sake of an example, let’s now
design a neural circuit that performs the same function without
any rule-based intelligence.
Figure 8.19 uses an 8-pin dip single-voltage-supply dual operational
amplifier (op-amp). The op-amps are configured as comparators.
Comparators were covered more fully in Chap. 5. If you have any
questions about Fig. 8.19, review Chap. 5. Two CdS photoresistors
are wired in series forming a voltage divider. The output of the
Team LRN
Behavioral-based robotics, neural networks, nervous nets, and subsumption architecture