A Deck36 (Aliens) Motion Tracker - Working electronics

[erv]

That one has been on the back burner for a long time. Too long.
Long story short, I didn't have the ressources back then to get vintage parts for that prop.

I got a Deck36 kit from spatcave on ebay. Cheap, like 60-70 USD from what I remember. Sounded like a good idea.

When I got the kit, some of it was nice, but some parts dislocated / changed of shape, like if the PU resin was still floppy for a while. Or just an aged kit, parts pressing on each other in the storage box they were in, even if I'm sure spatcave stored it the proper way.

Some parts I saved with a hot air gun (on low temp) and a lighter, getting the plastic hot and reshaping the parts. Everything was going well. Then the upper body mess. That part I could never paint it. I think the problem is called resin weeping or sweating. Since PU resin is made of a sort of "oil", if you don't mix properly with extra care prior casting, you can have either some oil OR some catalyst not mixed properly and it will go out for ever. I tried hot water, bath of acetone, vinegar, primer, resin, bondo, nothing will stay. Not on all the surface, just on a few spot.

The project waited until chimera bespoke (UK) and I talked about his armor & blaster projects, and since he's a fantastic caster, he re casted the part for me for almost free.
The issue is that the part was damaged a lot during all my attempts of covering it with various products.
Anyhow the cast was NICE. So I started over.

The project won't be very "accurate" due to the kit format & no vintage part. I could still get a vivitar flash and the flash calculator card but I would prefer to save that for a screen accurate project if I ever make one. Still I have big plans for the electronics, to make FAR better than the MR version.

december 2007....
The upper body mentioned above is the top part with the white/clear washer and the black rod inserted in it.
Sanding / bondo time...

[fast forward]
02/10/2010
the new casted part. Needed some filler.

I plan to have working switches here and there, so I placed one in the hama remote

Testing the placement. I knew from here that there will be a naughty seam between the upper and lower body, I used some bondo to minimize this but still... That's due the the part wall which bended inward. I forgot to fix that prior molding / casting. Too late.

ahhhhh... my mobile bench and painting cabinet. Sorry to be pleased with myself. The air exhaust is so nice, no more paint stinking in the basement, vapors are taken out almost instantly. I let the fan on during the oven pre heat then I bake the primed parts at 45-50°C (not really baking and it's not Powder Coating, just a way to get the solvents out quicker and it hardens the paint).

Visible results. I didn't search for brown bess, I don't have an airbrush. But I spotted some spray cans of special automotive plastic paint. Supposed to be "grey" but at the end it's an interesting tint midway between grey and olive dab. Matching very well my M-40 ammo box I got from Tommin/M41-A.com.

Making a battery pack. 2x16340 pre charged to balance the pack.

testing the future screen. That's the touch version for prototyping, the final thing won't have it of course.
Next is to start the electronics. I have many ideas. For now, collecting MT sounds. I'm seeing with XL also for a possible set of Flash videos.
Back in the day, I started a frame by frame work for a smaller screen. Not looking good I know. The new screen is 320x200 65k colors or something. It plays videos too.

 

[erv]

Here I am for the details...

My Motion tracker is equipped with a GPS and a compass (tilt compensated).

The goal is the next :
- the compass is controlling the orientation of the display which is rotating just like in the movie.
- the GPS is used to measure the distance to the alien fictive spot that was recorded and stored before

So, the interaction is kind of reversed since you're moving to the aliens and not the opposite but, still, it's very nice ! I initially though about building a RF beacon transmitting the actual position of the target to play hide and seek with my daughter but she's too young and the sad truth is that we kinda play alone with our expensive toys right ?

I was using a 5 Hz GPS head that fits perfectly in the motor area of the kango drill. The metal mesh isn't doing a faraday cage and the GPS signal is loud and clear.
For unknown reasons the GPS head died after some use (no change, switched the unit off, went back later, GPS dead), I ordered a new one and in the meanwhile, I had to hack an old one.
I started by removing the RS 232 voltage level shifter chip and bridged them to get some 3.3V I/O to connect to my boards.

The GPS head I have now is too long, so I had to remove the front disc. Once I'll have my 5 Hz one, I'll be able to finalize the prop.

To avoid magnetic perturbations from the electronics and speaker (all in the hama slide viewer) I move the compass in the jobo lamp.

first test of the screen installed

I shielded a bit the speaker area

... and drilled some holes for the sound (another option was to put it in the body of the kango but it made more sense to me to have it close to the electronics

The MT has several "menus" to either operate or configure the unit. I'm using the rotary switch to select mode and menus.
In the lowest position of the rotary switch, the MT is idle, you get the rotating display but it's not beaming.
Position 2 : it beams and whistles if it finds the aliens, and displays the distance
Position 3 : the GPS menu, displays the current coordinates, the alien spot saved coordinates, and the compass and current angle of the aliens from your current location, which can be a "cheat mode" is you don't remember where to search. That's also where you can save a "way point", then current GPS location will be recorded as the alien spots. To record the way point, I use the hama remote release switch (functional).
Position 4 : system info menu, where you read the battery charge and voltage, and current interaction mode (further explained). I had fun with the sprites, when you enter the GPS menu, you get a "door" sliding right unveiling the GPS info screen. The blinkies are made of sprites too.

kudos to that guy who made the sci fi panels and textures. I only assembled them in a custom way but it's not my work.
Texture gallery part 15

Since I wanted to be able to play with the MT indoors (GPS won't work inside a house), I also integrated a motion sensor. It's hooked up so that even if left unattended, it's using it internal noise to simulation motion : you'll get the aliens coming to you even if you stay in place. And if you move, you accelerate the process.
When in inertial mode, the hama remote release switch is used to reset the alien distance and angle. The distance is within 20 and 28 meters so that it can be whether or not within the range of the screen, and the angle is computed to be within the field of "view" of the current orientation of the MT using the compass so that it's not a PITA to play with it.
I started by making real inertial calculation to measure the route taken by the user (works if made over a short term trip) but it makes the gameplay REALLY hard and not really "fun".

Current Limitations :

- improve the filter on the compass. It's compensated but I sometimes get magnetic perturbations that make the display going crazy for a short time ("I AM READING RIIIIIGHT !!!!!" ). I'm currently using both linear and non linear filtering but I still have to adapt the filtering parameters to get it smooth enough and flicker free.

- the GPS isn't just giving you a position, it's working on a navigation "fix" (solution). When you record the way point, even after staying still for a while, when you'll be walking to the alien spot the GPS will estimate your position based on your current speed and direction (course over ground). In general, unless you walk very slowly, you'll miss the spot by 1-2 meters.
I'm working down to 1/10000 of second of arc which is about 1.85 meter (theoretical resolution), however, in practice, at least with the GPS head I have, it's more like 2.5 to 4 meters. Still, it's working very well till you're at 5 meters of the target.

videos :

here's a little demo video of the screen (WIP). Please do not focus on the artwork of the screen, I *know* the beams (and ghost beams) aren't 100% accurate. Still, those a fully changeable and redoing the 600+ frames takes about 40 seconds only (then add 30 sec to upload the contents in the screen).
Artwork I'll fine tune later, for now I had enough work on putting all the electronics together.
To avoid making a huge media list in the screen, the 630 frames are further grouped in a AVI file with no compression (raw RGB). I access the frames internally with the code I wrote for the screen.


MT screen WIP

Playing with the MT in my garden :

YouTube - MotionTracker WIP Part2


enjoy ! Question / feedback welcome as usual !

 

[LDR]

how cool is that. A WORKING motion tracker!

 

[Critic Proof]

Oh, man. Ultimate badass. State of the badass art.
You should be very proud. This is easily the most impressive motion tracker I've ever seen.

 

[kysupernatural]

:eek...OMG...That is simply...AMAZING !!!!!!!!!!!!!! Well done, can't get over how cool that is.

 

[SomeGuy]

This is pretty phenomenal stuff right here.

 

[darthgordon]

:eek This must be the most awesome prop I have ever seen... it actually works...

 

[ecmagee1984]

Bad Ass

 

[Mr Webber]

That is incredible, love your work.:cool

 

[Holluba]

It never ceases to amaze me just how many talented people there are that hang out around here. This is just spectacular! I wish I had the talent to perform such electronic wonders.

Holluba

 

[Vincenzo330]

That is amazing! Makes the Master Replicas version look like a Fisher Price toy

 

[erv]

thanks for the kudos folks. I've attached the sling, better placed the compass, and glued the meters and the calculator keypad. Almost there.

I planned to finish the code during the WE then post the beauty pics.

 

[Fluxcapacitor]

I LOVE THIS! These are the kind of props I love to see and build. This gives me such a prop woody! I would love to have one of these built this way.

 

[Stelios]

This is fully amazing. I love how the pings and halos track in the video. Ever thought of making a retrofit kit for the MR version? I'd hack mine in a second to install your electronics!

 

[erv]

This is exactly what has been considered during discussions over aliens legacy forums. I would need to acquire a MR one to see if it's doable and how easily it can be gutted.
I didn't come over the RPF in purpose to make runs, however, if there's enough interest about a kit, I might build one.

For now, I'm waiting for a new compass to improve the direction sensing. I've also reworked the placement of the current compass to improve readings, as well as the linear and non linear filtering techniques, now the screen is very steady and jitter free.

I'm currently working on :

- random number of aliens in the beamed blob

- the "crazy screen" that can be seen in the movie (at about 58 min) where hudson can't lock his MT. "Multiple signals, can't lockin, they're closing"

it will be a real time animation of multiple targets moving on their own, getting closer and closer, with the display rotating at the same time.

To have the system installed in a MR, so far :
- the jobo lamp must be disassembled to install the compass (that the best place). The self timer box can be used for that too. You need to drill thru the body of the kango drill to get wires running.

- batteries you can install pretty much where you want, I chose the handle cause it was convenient for me. If the MR is built like a real kango drill, it can be done too.

- is the sceen section a genuine hama slide viewer that disassemble like a real one ?

- is there a working rotary selector/switch in the bottom ?

if one has detailed & good quality pictures of the MR motion tracker, feel free to post here so that I can study do-ability. Thanks a lot !

Erv'

 

[Fluxcapacitor]

I don't care if this would be my only aliens prop but i want one just because it works. I wish I was working right now so I could afford one. Atleast wish I could work on the enclosure while waiting to afford the electronics.

 

[ARKM]

Simply awesome. Excellent work as always erv.

 

[precisionk]

Awesome! I look forward to seeing what else you are going to come up with.

 

[DRD50]

Mind blowing work there!

It's great to props with working lights and gizmos.
It's AWESOME to see a prop that actually functions.
Big time kudos to you, erv.

Thanks for sharing your progress.

 

[erv]

thanks a lot

as I'm rebuilding the sounds by hand, I went back to the movie, extracted the scene where they weld the doors and measured the frequency of the beams for known distances to target (distance is said or shown on the MT).

I then made a linear estimation and got pleasing "round numbers", ie a increase of 100 Hz in the pitch for each meter of the target getting closer

http://www.plecterlabs.com/Media/MotionTracker/Freq_Measurements_FromMovie.pdf

to get something even more accurate, I'll probably increase the amount of different sounds for the beams. Ideally 25-27 sounds, 1 per each meter of distance.