GrowBot is a ~200 USD kit with a stamp microcomputer, 2 servos for motion,
serial programming interface, light resistors and bumpers
First I programmed a obstacle avoider using mostly the light resistor
readings to avoid dark places while not going too much for light only
this is a Real Video (850kB) with this
behaviour, here another Real Video
(200kB) with a more closeup view, and the last
one (1.5MB) is a view from fall 2001
with the distance sensor on the servo
Growbot is meant to be a growable platform, and in 2002 I added a servo, a
ultrasonic sensor and a IR sensor
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You see the ultrasonic sensor mounted on a servo mounted on the GrowBot. It
pans from side to side when driving
In front (the right) you see the ultrasonic sensor, the white plastic at the
back is the infrared sensor.
The IR sensor detects persons (and pets) on top, to the left and right of
GrowBot.
If there's nothing to detect for the IR sensor, it stops driving after some
time
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Detail of the ultrasonic sensor - I had to put in this
blue wire so it can detect anything with Vdd at ~8V, this device was
designed for 12V. As this is just a test layout, I glued the sensor with hot glue on top of
the servo - it holds better than expected
The ultrasonic sensor needs 3 wires: Vin (orange), Vss (black) and the
signal (white). The resistor keeps the signal high until the sensor detects
something and pulls it down.
The servo needs power (blue and black) and a PWM signal
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No, this is not the plug for the Reset Switch - I am using old
computer cables in my robotics. See the Stamp II on the left. Both sensors
plug neatly in the AppMod extension bus. The IR sensor has just 3
connections: Vss, Vdd and the signal
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And here you see the ultrasonic sensor from the front.
This devices was meant to be installed in a garage as a parking helper. The
LED (now missing) would come on when the car has the right distance from the
wall. Kits like this are often cheaper and easier to use than buying and
building sensors from scratch.
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