Right then. The mission: to mount the Hydra’s base station under my desk, which means mounting the EM globe sideways. It’s the bit that generates the magnetic fields that the handsets use to sense where they are, so mounting it sideways will confuse the computer unless I reconfigure the coil connections.
I’d got this far last time:
Hanging out the bottom of the globe are two sets of LED connections and 6 enameled coil wires. Quickest way to find out which wires go to each coil is to split the globe open:
Following the wires to the coils, I could draw a quick picture:
I wanted to mount the globe tilted forward by 90°, so the x-axis coils are unaffected, but the y and z axis need to swap over. The z-axis coil would now be pointing the opposite way to the original y-axis coil, so its wires needed reversing as well.
Time is tight (when isn’t it?) so rather than machine a nice bit of plastic to house everything I just screwed it all to an offcut of wood and used cable ties to tie the globe on.
Had the good sense to mark the connections on the top of the PCB before screwing it down, so soldering the wires back on in their new configuration was simple enough.
Time to stick it under the desk… this is why I need to do this – my desk’s got too many keyboards and gizmos taking up real estate already, so having another big ugly thing sat there as well wouldn’t be practical. I’d end up never bothering to use the Hydra.
A couple of carefully chosen woodscrews later, and:
Not pretty. But it works! The handsets seem to work fine even through 2/3″ of wood, and the odd wires and LED strips running along the front of the desk don’t seem to phase it. I haven’t run into any issues with the handset docking/configuration process yet (I just haven’t bothered trying to dock the handsets at all), but that could just be hacker’s luck. Fingers crossed it’ll keep working.
Next step – gotta write a plugin for Blender so I can use the Hydra as an animation controller. I suspect this’ll be the tricky bit 🙂
Very nice to see you finish this. I did buy a hydra and am thinking over my own mounting possibilities.
Thanks for taking the first step when it comes to hardware modding the Hydra and for documenting the whole process. It makes it a lot easier for people to take the dive into modding when they can see that it can be done with success.
Great teardown Howie. Now which of the manufacturer’s labels are negative vs. positive, dots or lines?
Dunno which are positive vs negative, but it’s all relative so it doesn’t matter as long as you keep track of how they were connected initially 🙂