Page 349 - Amphibionics : Build Your Own Biologically Inspired Robot

Amphibionics 07 3/24/03 9:13 AM Page 328
FIGURE 7.29
Encoder disk.

TABLE 7.5 Part Amphibionics Quantity Description
Optical Encoder Parts
H22B1 Optical 1 Photodarlington transistor
List
interrupter switch
R1, R2 2 1 K 1/4-watt resistor
R3 1 470 K 1/4-watt resistor
D1 1 Red light-emitting diode
Three-strand ribbon wire 7 inches Connector wire
header 1 4-post male connector—
2.5-mm spacing
Hot glue — Hot glue and gun

The schematic to interface the interrupter switch to the PIC 16F84
is shown in Figure 7.30. The circuit operates by using the transis-
tor as a switch. Cut a piece of perfboard to a size of 1-1/2 inches
3/4 of an inch. Create an aluminum mounting bracket by fol-
lowing the cutting, drilling, and bending instructions in Figure
7.31. Use 1/16-inch thick aluminum to construct the mounting
bracket. When it is complete, position the 3/4-inch side of the
mount on the left side of the perfboard and mark the mounting
hole. Drill the hole with a 5/32-inch bit. Attach the mount to the
perfboard with a 6/32-inch 1/2-inch machine screw and lock-

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