gauge solid wire. After soldering the jumper wires, solder
the resistors and IC socket. The socket is technically not
polarized, but do watch its orientation so you can plug the
hex inverter in with the correct orientation. The 4. 7 µF
capacitor is polarized along with the IREDs. However, the
5K trimmer and 1 nF (1,000 pF or 0.001 µF) capacitor
Bend the leads of the 40 kHz detector to a 90 degree
angle and mount it flush to the PCB. You’ll notice in the
photo of the proximity detector that the 40 kHz detector is
upside down compared to the diagram I made for the parts
placement. That’s because the picture is of an older design.
I’ve since corrected my PCB design so you won’t have to go
through the trouble I did to mount the detector. There are
two mounting holes in the proximity detector PCB.
Proximity Detector Sample Code
Here’s an example of code that will have a
CheapBot- 14 robot drive around obstacles:
IF Detectors = 0 THEN Wall_in_Front
IF Detectors = 3 THEN Dont_Crash
IF LeftDetect = 0 THEN Wall_Right
IF RightDetect = 0 THEN Wall_Left
An inexpensive radio for robots. I use this one to send
commands to and from my MoonBot Robot.
Detectors = 0
RightDetect = PIN4
LeftDetect = PIN4
SparkFun sells a really nice radio transmitter and
receiver, and thanks to Barry Nye of the Boise Robotics
Two parts and eight
wires — that’s all it takes.
Now you can send
commands to a robot
and have it respond.
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