Master-Slave Bicores

345

03:20:25

The design patented by Mark Tilden and a key curcuit in BEAM Robotics. This analog approach to robotics uses timing cycles as the basis of information in the control of analog robots. A surprising degree of ability results from a very low transistor count. This circuit would be most commonly used in a two motor walker. 

The 'suspended bicore' at the top sets the overall pace and drives the front motor. The resistors connecting to the lower bicore set a phase delay of approximately 90°, and drive the rear motor. The timing of the signals stabilizes within the first few cycles. 

Sensors can be added to adjust the duty cycle of the square wave to allow, for example, phototropism and other behaviors. A simple analog multiplexer can be added between the bicores to give reversing motion.

To see a bot like this in action you can check out this video (I have no association with the creator). https://www.youtube.com/watch?v=2ZwcM6q7AUM

published 4 years ago

faceblast

4 years ago

I love beam bots ever since I read about them in the nineties. is Mark still making them?

Ezrin

4 years ago

I was quite into them around 2000 myself. I am just getting back into it after all these years, and from what it seems it is a much smaller hobby now, and I don't know that there is the degree of community and innovation that used to exist. But there certainly still seems to be a number of people building them. Mark himself went on to design Robosapien ( a very successful robotic toy) around 10 or 15 years ago as well as a robotic dog and dinosaur toy. He used BEAM principles in those designs, and seems to have done quite well for himself.

faceblast

4 years ago

is anyone still actively making bots? the old sites seem to be dead

Ezrin

4 years ago

It seems to have faded among hobbyists in competition with things like Arduino and Rapsberry Pi, which is unfortunate since BEAM was sort of a rebellion against the digital and a pursuit of minimalism. I'd love to spread the word and see the hobby get a new kick off. Many if not most of the old sites are archived, so the info is not lost but much harder to stumble upon. Here are a couple more recent links: https://beamrobotics.blogspot.com/ https://www.digikey.com/en/maker/blogs/2019/top-beam-projects

Ezrin

4 years ago

A few more links for general info from much older sites - http://solarbotics.net/library/circuits/default.htm https://web.archive.org/web/20120814061320/http:/www.beam-wiki.org/wiki/Main_Page https://beambotics-archives.tk/

lensrulz

4 years ago

http://everycircuit.com/circuit/6451504434905088

Ezrin

4 years ago

Howdy lensrulz, when I try your link it says "Can not display private or deleted circuits".

lensrulz

4 years ago

@Ezrin, sorry for the inconvenience, should work now...

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