Howto attach the 6x AA case to the BrickPi case


#1

Hey folks,

I just got my BrickPi and my BrickPi B+ Case.
I also bought this 6x AA battery holder: http://www.amazon.de/gp/product/B000QJEU1K

I am now curious, how I can attach this battery holder to the BrickPi B+ case. Any examples on that?

Best,

Daniel


#2

No pictures yet. But your best bet is to probably make a cradle with LEGO parts.


#3

It isn’t an answer to this question, but as an alternative solution, I was wondering about using a Power Functions battery box. One could either hack the box to get 9v leads, or cut a Power Functions cable, and leave the box intact.

Using the Lego cable makes the solution a bit expensive. But the box itself offers versatility and elegance in terms of attaching batteries to Technic/Mindstorms parts, and it has a built in switch.


#4

Hey Bret,
this is a great idea! Love it, especially since it can be mounted to the LEGO so easily. The only thing I would be careful with is that you get the polarity right before you attach the wires and turn it on!

Thanks,

John


#5

Good point. Especially worthy of consideration given the nature of the polarity reversing switch on the box–middle position is off, and the two outer positions reverse the polarity, with no indication of which is which.

One could mark the correct position, but in practice that is insufficient for an application that might be damaged if connected backwards. One very frequently pushes the switch too far in the attempt to turn the box off, switching the polarity before power is finally cut.

The switch does have an axel hole built into it, so one could make a custom cable with one end suited to the BrickPI, and the other (battery box) end either limiting the switch’s movement between off and one of its on positions, or alternatively holding it in one of the on positions (both options allowing the cable to guarantee correct polarity).

Be aware, though, there is a small LED on the battery box that indicates the box is live. It doesn’t burn much, but it shouldn’t be left on permanently.

Best option (I think) is a custom cable that limits the switch between off and one of its two on positions, guaranteeing correct polarity.

Second best option is a custom cable that holds the switch in one of the two on positions, and has to be uncoupled from the box to turn the box off. Given that the electrical connection to the box is a single-position studded lego connector, the second option isn’t less functional by any significant degree. It is foolproof, and simple. It would just a little less elegant. You might even call it klugetastic!


#6

For those not familiar, here is a good picture of the connector and the switch.