Let's Make Robots!

Brushbot's Blog


A whole summer came and went with little progress on any of my outdoor solar bots. LMRbot and Hexaspider ate up my time successfully. I blame them :) With another summer approaching I gave my project list a thorough reconsideration.

I'm currently spending some time on my solar swarmbot project which finally has a little traction in the concept department. The current plan is to have them run off 3.7V lipos and recharge with a solar panel. The great question I've had weighing on my mind is, "What are they swarming for?" That's where the "induced coma" for Brushbug sets in. I'm thinking of implementing the same horse/jockey idea from Brushbot just with the Nanomuscle/SE assembly riding a different horse.

So with that being said, even though Brushbug looks dead, it's merely waiting for a higher purpose.


Brushbug has come to a virtual standstill. Both the seeds on my porch and the sunlight that used to shine on them are both gone till the spring. That has lessened the drive behind the project, sadly. Plus I've commandeered the chassis Brushbug was using for Crumbot again. Development wise I've been a little daunted by the fact that I needed a 4.7F supercap to naturally power a Nanomuscle.


All the bits have come in and I just got done tinkering with one of the Nanomuscles. I first started with a 5.5V @ 40mA panel hooked up to my bristlebot's Miller solar engine (configured with a 1381J, 4700uF storage cap, and a 1uF timing cap). It seemed like nothing was happening. To make a long story short, I checked out a 1F cap with various configs and ended up plugging in the 4.7F supercap that was intended for the robot's Maxibug circuitry. Paired with a 1381S and a 10uF timing cap it made for one exact sweep through the Nanomuscle's travel. If given constant power they power on and off to make repeatative motions, they don't just stay on and stick there. Unexpected, but it just meant I had to get the timing cap just right. No problem.

A single muscle doesn't have much torque. I'll have to see how two actuators work together in regards to power consumption and synchronicity. It looks like I'll need to start looking for gears too. Perhaps gearing right around 1:1. I saw some gear sets at allelectronics.com that I'll probably get with a bunch of their pager motors they have.

Weather is hazy here in SoCal recently so it's been slowing my larger sized solar projects. I still have the Maxibug circuit occupying a precious breadboard and need to construct the 6V solar panel array so I can be ready for when the sun makes its next appearance. After that I can see if the 4.7F supercap is a suitable storage cap for moving the robot around.

Still need to get some guitar string and fab up my passive edge/cliff detection feelers. Plus I just broke my only set of generic tactile feelers after being on three different bots. I think I'll just buy a handful from Solarbotics just because of the hassle factor.

Plenty of things to do.

Plenty of money to spend.


I couldn't control my compulsion to push this robot along, even though the coming season doesn't really promote solar projects. There's thunderstorms here in San Diego already :sigh:

I sunk a chunk of money into a couple rotary Nanomuscle units, three 6v @ 100mA solar panels, three 6v @ 35mA panels (two to run in parallel to the 100mA panels, one for the brush's solar engine),  and a 4.7F @ 5.5V supercap for thrills. I also picked up a handfull of small caps to tune the oscillation frequency of the motors.

Now I just need gumption and sunny weather.