Page 132 - Amphibionics : Build Your Own Biologically Inspired Robot

Amphibionics 04 3/24/03 8:24 AM Page 111
Chapter 4 / Frogbotic: Build Your Own Robotic Frog
lets go, the robot does not always leap forward. This introduces an
interesting random element, and this is the key to actually con-
trolling the robot’s in-flight direction. If you want to add sensors
and direction control to the robot, try writing a routine that will let
one of the legs release, and wait for a predetermined amount of
time before letting the other leg go. These values could be depend-
ent on the information that the microcontroller receives from the
sensor input. Compile frogbotic.bas listed in Program 4.5, and
then program the PIC 16F84 with the frogbotic.hex file listed in
Program 4.6. Insert the PIC 16F84 into the 18-pin socket on the
controller board. Place the robot on a flat surface and turn on the
power. Note that the robot should not be used on hardwood or
other types of flooring that scratches easily.

'------------------------------------------------------------------------------------------------------------------------------ PROGRAM 4.5
' Name : Frogbotic.bas
frogbotic.bas program
' Compiler : PicBasic Pro MicroEngineering Labs listing
' Notes : Program to coordinate the jumping of
' : a robotic frog
'------------------------------------------------------------------------------------------------------------------------------

' set porta to inputs
trisa = %11111111

' set portb pins 2 & 3 to inputs
trisb = %00001100

'------------------------------------------------------------------------------------------------------------------------------
' initialize variables

servo_pos_l VAR BYTE
servo_pos_r VAR BYTE
timer1 VAR BYTE
timer2 VAR BYTE
timer3 VAR BYTE
temp1 VAR BYTE

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