Razer Hydra base station teardown

Just got hold of a Razer Hydra, a 3D motion controller system aimed at gamers. There’s a base station with a glowing green ball on the top that needs to sit directly in front of you, and two handheld controllers with buttons and joysticks on them. They constantly feed back their orientation and position to the computer, so you can wave them in the air or twist and turn them, and objects on the screen follow along. I’m not into them as games controllers (prefer the ole mouse and WASD meself) but with a bit of hacking and help I’m hoping to use them as motion controllers for my graphics work. Record my motions as I manipulate the controller and apply them to, say, a character’s head on screen. Quick and expressive way to animate secondary characters in animations. Nothing new, but this is dirt cheap – £80! – so well worth a punt, and not the end of the world if I can’t get it working.

The base station is way too inconvenient (and has too many wires attached) to be sat there in the middle of your desk all day. That’s precious real estate, and I’ve got a system for my various keyboards where I can slide ’em in and out under my monitor stand, and that round thing just doesn’t fit.

The base station seems to work just as well upside-down, though, so I’m going to try sticking mine under my desk. (The base station uses a magnetic field to sense where the controllers are, so this trick won’t work with metal desks, and possibly not with very thick wooden ones, but mine seems to work OK. So far.)

Damn thing is too tall, though,10cm-ish, and I’d keep knocking it with my knees. So let’s void its warranty.

Even knocking a few centimetres off would help; I know the coils that let it do its magic are housed in the black ball on the top, and I’m hoping we can get that off and mount it to the side of whatever’s in the bottom section. Slim the whole thing down.

Ahh yes, the old hide-the-screws-under-the-rubber-feet thing.

Take out the 4 little screws, take off the bottom cover and …

… another bottom cover. Only three screws this time.

That’s better – a PCB. Two little screws holding it in, then you can lift it.

Two sets of connections on the other side: the red and black wires with plugs connect to the green LEDs in the ball (I guess), and the fine enameled wires go to the EM coils. Have to be careful not to wiggle them too much – they’re solid wires, susceptible to fracturing – it’s OK if one breaks out near the PCB but a break further up inside the ball may be difficult to fix.

They’re labelled already, along with their connections on the PCB, which saves me having to do it. Out with the soldering iron to disconnect them.

The stem of the ball section is held into the base with plastic tabs; they’re pretty springy so it’s not too tricky to work it loose…

OK, I guess it looks slightly Hydra-esque…

Wish I had some googly eyes to stick on it.

Can’t see any electrical reason why I can’t mount the ball to the side of the PCB instead of over it, which is good, and the ball with its little stem is only 6cm high. That’ll do.

Docking: there are two recesses in the top of the unit to rest the handsets on, and apparently the base station will recognise when they’ve been docked, and use it as an opportunity to work out which handset is on the left (they’re easily interchanged), and which hemisphere the handsets are in (… long story. Briefly, the sensor information is ambiguous as to whether the handsets are above and in front of the base station, or below and behind it. When docked, the base station can assume its readings mean the handsets are above the dock, and from then on it’s easy to keep track)

So it’s all very well pulling the ball off the top but I still need to be able to do the docking / configuration thing. How does the base station know the handsets are docked? Can I fool it?

Worth looking at the rest of the case, then, just in case there are any other secrets in there. Suspicious number of screws.

Nope – turns out it’s all just boring bits of plastic. You could possibly use the conical part the ball stem clicks into:

… to make a simple stand, but it still stands too high for me (around 80mm).

It’ll have to be a custom mount, but it only needs to be simple; a 30mm diameter hole in a 15mm thick bit of acetal should do…

But that’ll have to wait ’til another day. Got to get some code working between it and Blender in the meantime…