Download robotproje1

MAIN COMPONENTS
Programming connector bag
Motor brackets
Chip Holder
Microcontroller chip
Piezo Sounder
Circuit
components
switch
Terminal
connectors
Circuit Board
Battery Holder
Motors
Circuit components :
BC639 labelled
8 transistors
1 resistor
1 LDR
3 ceramic disc capacitors
1 bead capacitor
BC640labelled
47K resistor
LDR( sensor)
Light dependant resistor
100nF ceramic
disk Capacitor
Bead capacitor
Small leg negative
Very important: there are 2 different types of transistor
BC640, and BC639 both work differently so you must get these
Soldered in the correct position otherwise the circuit won’t work!
Robo Scorpion!
Acrylic chassis
Left Touch sensor
Digital/ on/off
Piezo sounder
Light sensor
Right Touch sensor
Digital/ on/off
Motor spindles run directly on the ground, must not be vertical
ROBO SCORPION!!
The Robo Scorpion is a programmable 8-bit computer running at 4 Mhz. It is pre-programmed
to head towards light while avoiding obstacles in its path. The robot has two digital touch sensors,
an analogue light sensor and a small sounder which ‘chirps’ during its operation.
It can also be programmed while it is in ‘edit’ mode via a serial data link to a PC using your own
Instructions.
TOP VIEW SCHEMATIC
Very important: there are 2 different types of transistor
BC640, and BC639 both work differently so you must get these
Soldered in the correct position otherwise the circuit won’t work!
CIRCUIT DIAGRAM
If you want to know how this works read the
Following page!
HOW IT WORKS
U1 is a complete computer running at 4MHz. Pins 2, 3, 5, 6, 7 can be used for input or output; pin 4 is only
for input.
U1 controls the motors by switching the transistors T1..T8 on and off. To slow the motors down and use less
power, they are switched on and off around 200 times a second.
If output pin 2 of U1 is low then T1 is switched off and T2 is switched on. If pin 3 is high then T4 is switched
off and T3 is switched on. So motor M1 runs forward. If pin 2 is high and pin 3 is low then the motor runs
backward. If pins 2 and 3 are both low or both high then the motor stops.
Likewise, U1 pins 6 and 7 control M2.
If the right antenna touches something, it is connected to 0V and this is sensed by pin 4. The left antenna is
sensed by input pin 5. Pin 5 is normally pulled high by the LDR.
When a Sound is required, pin 5 temporarily switches into output mode and toggles up and down at 2kHz to
3kHz.
To measure the light, pin 5 switches into output mode. It goes low to discharge C2 then switches into input
mode. The capacitor slowly charges through the LDR. In low light, the resistance of the LDR is higher so C2
takes longer to charge. So the time it takes for pin 5 to read "high" (around 2.8V) depends on the light level.
(In dim light, the resistance of the LDR can be too high - R1 helps charge the capacitor.) As pin 5 toggles, a
click can be heard from the Sounder. Different resistors can be used to adjust the sensitivity.
The serial programming lead
For extension work the robot can be programmed
Via this lead. It uses the l.e.d to flash the program into the
LDR of your robot while it is on and in edit mode.
1k resistor
The buggy is initially in edit mode when it is turned on.
Please note that the lead is for the serial port of a windows PC. A USB to Serial adapter lead
will have to be used if your computer does not have a serial port ( latest computers may not
have a serial port anymore!)
Side view
http://www.youtube.com/watch?v=qNEOI7bYl3c&featur
e=related
http://www.youtube.com/watch?v=n9yixR2ykB0
http://www.youtube.com/watch?v=BQYEKQUF0_c
http://www.youtube.com/watch?v=paHcqN9iarg&feature=related
http://www.youtube.com/watch?v=6ZnmmEQXSmI&feature=related
http://www.youtube.com/watch?v=4u7aIIUDSQk&feature=user
http://www.youtube.com/watch?v=gwZD59Ic9T8&feature=related
http://biorobots.cwru.edu/
http://marsrovers.jpl.nasa.gov/home/index.html
http://www.jpl.nasa.gov/news/phoenix/main.php
http://www.1robotics.com/products.htm
ROBOTIC EXPLORERS
First Color View of Titan's Surface
Pictures courtesy of JPL