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Priel
20th January 2014, 12:53 PM
Hi, just got my package with Cinemizers and mask! Rob asked me to do a build log here so I will do my best. It's a bit of a ghetto build, be warned... it's fast though, took me about an hour ;)

First I drilled a hole to mount the tracker reset button. The mask is made of quite soft plastic so an exacto knife works great.

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Then I cut some pieces of 6mm depron, to use as padding in between the mask and the goggles for the correct offset to my eyes. The pieces were 13x3,5mm and 13x2mm. Place these in the mask, the fatter one at the back and thinner one on top. No need to glue them, they will stay in place by friction.

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Inserted the goggles into the mask. I moved it around a bit and for me the fit was easy as it looked good when the goggles rested on the bridge of the nose of the mask, very slightly tilted forward. I grabbed my hot glue gun and held it in place while it dried.

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I inserted the cable through the foam area where there is a hole, just cut up the foam and slide the cable through. I had a problem with the little clip-on plastic thingy that snaps the ribbon cable to the connector. One of the legs was broken so couldn't use it. Wasn't a big deal as I hot glued it in while holding it in place.

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Rob was so kind and modded the cable to hold 5 extra wires for my head tracker, I realized I only needed 3, but it's nice to have some spares. I soldered up the red,black and green (5v, ground & ppm). Put some heat-shrink on the others just for safety.

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The DIY headtracker need to be installed laying flat to function properly. So I put some double sided tape on the two pcb boards (one is the Arduino, the other is the sensors. The small pin connection to the right is for flashing future firmware.).

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I inserted it on top of the goggles, pushed it as far in as I could.

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That was pretty much it. After testing them and walking under a strong light source I noticed that they were leaking light. I kicked myself as I suddenly remembered Rob telling me that I should probably black out the lighter colored masks as it didn't block out as well as the black ones. I live in a hot tropical climate so wanted a light colored mask due to the heat... In any case, I used some black cloth tape and cut small pieces to cover up the sides etc. I've used this kind of tape on other goggles and it works really well to keep light out. It's now pitch black.

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That's about it for tonight. I'll post my power box build tomorrow.

Peter.

Priel
20th January 2014, 12:54 PM
I first planned to feed the diy tracker with an external 5v source, perhaps by breaking out a cable from the usb connector. But after measuring the ppm signal from my trinity tracker, I noticed the peak-to-peak voltage was around 3.3v... this got me thinking that if the transmitter works fine with that voltage perhaps I don't need to go to 5v for the diy tracker. So I hooked up the diy ht to my power supply and dialed in 3.3v. Seemed to work fine, ppm signal looked identical to the trinity signal on the scope. My plan is now to feed the tracker directly from the battery, which needs to be installed anyway for the power-box to start up. I'll hi-jack the power before it enters the connector on the box, doubt the 15mA the tracker draws will matter much. The one thing I need to add is a small on-off switch though, so glued one in with goop... lets see if it holds. The lipo battery is 3.7v, so should be ok to feed the arduino with.. I guess since the usb charge cable will always be plugged in, the power-box shouldn't really care?

Any comments on my plan would be appreciated. I'm a little confused at which wires I should take the power from on the battery. There are three wires, I figure the red and black? White is for what..? Cant be balance since only one cell right?

Peter.

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Priel
29th January 2014, 01:03 AM
Still working on this. Found out that the white wire is most likely for a thermistor on the Lipo, and it does act like it since the resistance between the white and black (ground) wire decreases when I warm the lipo by holding it in my hand. Proceeded to install the switch and hi-jacked the power supply for the HT from the red and black lipo cables. I also added a small Pololu step-up regulator in the goggles to get to a proper 5v for the Arduino Mini Pro. Works great, very portable and only thing sticking out of the power box is the cable to jack into the transmitter.

Now for the problems... I can't seem to get the DIY HT to work at all. This HT was working fine in another set of goggles, but the minute I install it on-top of the cinemizer goggles, the gyro goes nuts. It seems there is a lot of interference that causes the gyro and accelerometers to misbehave... I'm going to rip it out and re-calibrate it again, completely removed from the goggles, however I have doubts it will work. Not 100% sure it's the cinemizers that cause this behaviour... but it does seem like it as the HT servos I got hooked up to test with, moves in a much more precise manner when I keep the sensor board away from the cinemizer goggles... will update here when I know more... Grrrrrr... I wanted to use these to fly with this weekend!

Ps. Is there a manual of any sorts for these goggles? I thought the brightness and contrast adjustments were more refined than what is available.. basically only three modes of various brightness...

Priel
20th March 2014, 02:39 AM
Realized I never closed the chapter on this build log! My issue with the DIY headtracker was just the calibration. It's very important, it seems, that the gyro is facing the correct way according to the pictures during the calibration process. Since mine is built differently from how the calibration images were taken, it took quite a few rounds before I got the sequence correct.

I've now had lots of flights with the cinemizers, and they are now my main goggles. Tracker works perfect, image is great and much more comfortable than the fat sharks. Also nice to only have one cable from the goggles to the ground station.

Peter.