I've been wondering how to power Arduino projects inside Nerf blasters.
I'd like to find something that young / beginner modders can pick up easily.
Let's take a case study. Adding LED lighting, say an LED strip chase sequence along the top of the blaster, which happens on trigger pull.
There are two types of blasters:
electronic - typically featuring 2x motorised flywheels - these take alkaline batteries totalling a nominal 6v or 9v (e.g. 4 or 6 standard alkaline cells).
"springers" whichare mechanical and have no on board power.
Many of my own "elecronic" builds ditch the alkalines for a suitably sized LiPo (with alarm) for motors etc and a buck converter / BEC to handle the arduino and everything else.
Similarly, if I were to put lighting / sound on a "springer" I'd probably use 2s lipo + BEC combo.
I feel that is a bit much to expect entry level modders to deal with LiPos.
Is there any way I am missing for powering such things? Multiple Alkalines or a 9v and using the 5v output seem to be so limited.
What I mean is that it limits how accessible these types of mods are for beginners. Particularly for those modding cheaper blasters that have no on-board power.
It seems a hassle to have to find space for an alkaline battery box (or make one), and wondered whether the Arduino community had a better solution
So... You are talking about the mechanical type of blaster which don't already have batteries. You don't want to have to find space for a battery box for alkaline batteries. You don't want to use LiPo. Did I get it right?
Presumably if you don't want to find space for a battery box for alkaline batteries, that would rule out NiMH batteries also? And does avoiding using LiPo batteries also rule out Li-ion, LiFe-PO4 etc.. also?
I'm not sure what else there is... Lithium coin cells don't have much capacity or current. PP3 9V same problem.
There can never be a specific answer to a generic mod. But it's usually easiest to mount a small rechargeable battery inside, and provide some external jack for charging. That's because minimal modifications to the case. Also you never need to open it again, except for maintenance.
I would choose 4x NiMH. This gives a voltage around 4.5~5V at most charge levels, which is enough to run a 5V Arduino and ws2812b LEDs without needing regulators or converters, which inevitably waste some of the energy. The danger here is that someone could load up 4x lithium primary cells, which would provide a damaging 6V.