Let's Make Robots!



it's the ultimate solar rover

based on Picaxe 18X

it soaks only 25 uA in idle mode

it have a brain

it's i/o modular through 2.5mm strips

it's efficient

it's small (L:66m W:37mm)

 the nemesis of beam robots


the actual schematic


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Each PICAXE pin can easily output 25 milliamps. Because the Sonimoro is so light weight, there is very little loading on the motor and the the power requirement is vey low..  I dug out an old BEAM test platform with the geared pager motors and measured the currrent at 25 milliamps.

Measure yours and try it!

The stall rating of 180 milliamps only occurs when the wheel is locked.




yep that cap would be great for this bot , 5,5v is ok


i have done some tests and it seems motor have enought torque to drive  thread bealts....

now i am trying to handcraft a decent drivetrain


what oddbot said, usually in solar robotics/and or beam supercaps are used instead or regular caps because they store a lot more low volage eneregy than normal caps, unless your using like 100 panels lol

thank you for the advice

about the cap now it's a bulk 6800 uF

and it provide enaught energy to drive both motors for 50 mS @ 3v

it's enought ini order to move 

bigger cap means longer motion period but longer idle time

anyway cap size have to be reduced


i was thinking about thread bealt

but i fear too mugh friction




supacap.jpgThis is the type of cap I was talking about. It is a lot smaller even though it's 47000uF.

I agree that treads would have too much friction.


i need some advice about the drive train

now i have put those two motors and the big belly capacitor


Nice bot, it will be easier to advise you if you give us more information. What is the maximum voltage you get across the capacitor in bright daylight? A super cap might be better. I've seen 1F super caps rated at 5.5V for about 7$ US. If you use a high intensity LED then you can get good brightness with less than 1mA.