Let's Make Robots!

Smoking PING)))) sensors

I didn't get arround playing a lot with my bot due to work/studie untill yesterday. Nothing changed and last time I used it all was fine and roaming (as shown in the video). So last night I had a visitor and wanted to show the bot, power on, but no movement. 2 seconds later smoke was comming out of the left and right ping (the little chip under the cq passed sticker turned to toast). I switched things off and checked for something that could cause a shortcut but all seems hooked up fine.

Anyone ever seen such a thing?

Hooking up a power LED

Hi Guys,

I installed a powerswitch on my bot that runs of an 11.1v lipo. Now I would like to hook up a LED that switches on with the power. Can I just connect a LED with a resistor to the switch (if so what value should I use)? Or do I need to use a voltage regulator to reduce the power?

It's roaming by now, I'll post some pictures etc. later this week. Did some serious liposuction on the thing and removed near to 7 kilo's. It's now small enough to run arround the house without moving the furniture or cause some serious damage to the kids :)

Reducing amp drawn on a dc motor

Hi there! 

Is there any easy way to limit the amps drawn by a electro motor? I ordered some good ones but am playing arround with a standard 360 one now. It comes of an rc plane, is small but rather amp hungry. Don't want to blow up the motorbee.

Best regards,


Strange servo movement

My servo's arrived finaly but now they don't seem to work. It's these:


The parallax and the old servo's I used so far don't have any problems. But when I hook these up I get some really sputtering movements. Even stranger, they make little movements even when there is no code running. Anyone a clue?

4 wheels or not to 4 wheels

I want to add 2 extra (fixed) wheels to my bot (front end) but wonder how that would behave when steering. Steering will be done by the motors on the rear wheels.


I'm redoing the base, it will have some suspension underneath the turret and a bit more batman like features (as I'm waiting on my servos still).


Is it possible to program a pic16c745

So I got the motorBee to work and pretty much doing what I wanted so I went on to the DigiBee+. Got some code off the site and started to play arround (visual basic, steeeeep) but eventually i managed to make the pir sensor turn on a led. On to the servo's. I read down the site 3 times, spent another 4 hours of crosseyed looking at my silly programming (pobably) but wasn't able to move anything a bit.

Putting 5 volts on a LED

I have a couple of LED's installed but when used with a resistor the light intensity is not that good (ultrabright LEDs). If I loose the resistor and hook it up to 5 volts it's great (and so far working). I guess I'm just drastically reducing the lifespan of the LED. Anyone a clue how long they will hold this way? Or of any other consequence?


IR leds, the PING sensor and resistors

As an absolute beginner in electronics I was wondering about a few things. Will IR proximity sensors be affected by IR LED lamps? This because I am thinking about adding one to the lazybee (just for playing arround with it) but I would also like to have some IR led's for nightvision (the cam can see IR light).

DC motor question

Is it possible to add position sensors to any dc motor? I want to buy 2 standard geared ones but am not sure if I would be better of buying a set of motors with postion sensor included. For now I don't really need them but it would be nice if would be able to use them in the future.



Hello all,