Suspended Bicore

• What is this circuit?

The bicore is the basis of advanced BEAM! Most intermediate to advanced BEAM robots are built off of the bicore. Uses go all the way from photovores to servo motor drivers to walkers to.... You get the idea. What it is is basically just an oscillator who's outputs go (+ - , - +, + -, - +....) and the rate of oscillations is controlled by the resister (R1). Another cool thing is that they can be grouped together to form large complex structures. Really a very cool circuit once you figure out how it works.

• What could I use it for?

As I noted above it has a very wide range of uses. Photovores, light seeking heads, walkers, servo motor drivers.... Just to name a few. The walker category is HUGE!! There's walkers with 2 motors to 12 motors. No sensors to electronic compasses and sonar. A single bicore can't do much other than blink a couple LEDs or make a motor go back (which is sometimes what you might want) but they are most useful in groups.

• Schematic

• Freeform layout

Same as above but with inverters ganged up for current on the outputs Pins facing down (top of chip)


Note that you can fit up to 4 bicore's on a single 240 chip.

• Parts needed for single bicore

Description	Quantity	Where to get	Part #
R1 (see circuit notes)	1	Digikey	See circuit notes
.22uF Capacitor	2	Digikey	P4966-ND
74AC240	1	Digikey	74AC240PC-ND

• Circuit notes

R1 R1 controls the rate of oscillation. If you want quick oscillations you use a low value resister, long oscillations you use large value resister. I normally don't use values below 100K or over 10M, 1.6M is a common value. The size of the resistor is totally application specific so there is no set value.

• Advanced bicore circuits, applications, ideas and hoe they work

Coming soon....

• PCB?

Yep, check it out.