Motion Control System for Red

[vtrifu]

I'm planning to build a high-precision motion control system for a Red cammera or even bigger.

Highlights:

- The system will be formed from a dolly running on tracks, a column and an arm, a remote head with 2 or 3 axes(not sure yet), remote focus and remote zoom.

- It will run on steppers. The steppers will control dolly movement forward and back, the rotation of the crane's arm, the elevation of the crane's arm, tilt and pan (+3th axis?), remote zoom and remote pan.

- You will be able to mount the remote head directly on the dolly, or on the column, or at the end of the crane's arm.

- The height of the column will be variable, meaning that you can set it mecanicaly between 2 boundaries before you shoot. Then you should stay with it.

- The length of the arm will be variable, meaning that you can set it mecanicaly between 2 boundaries before you shoot. Then you should stay with it.

- The software will allow you to set keyframes for each of these motors(position of the dolly, angle of the crane's arm, pan, tilt, zoom and focus), and then play them with an acceleration/speed at your choice(within the limits of the motors)

- Control by cable or remote. Probably a small PDA attached to the system, that is remote controlable would be the best solution.


I want to design the system especialy for Red, but on the second thought I think it is a good idea to have it support a large range of cameras. So here is my take for the system specifications:


Camera weight: up to 17 kg (is it too much? can I "get away" with less? how much weight a "heavy loaded" Red? What about using a "heavy loaded ARRI 435"? Or something else? Where should be the limit? The lighter the system is, the happier I am. I Would appreciate your oppinion on that.)

Dolly speed : up to 3m/s
Arm rotation speed ?
Arm elevation speed?
Remote head tilt and pan speed : (min) 360 degree in 6 min - (max) 360 degree in 4 sec (to slöw?)

Distance between tracks: 35 cm. This will allow you to film in very narrow places. This will be the option when using the system only with the head/ head and column. I have to see if you can rely on this small distance when the crane is also in place.

Column size: 1-1,6 m (colapsed/extended)
Arm size: 1-1,6 m (colapsed/extended)


Depending on this caracteristics the mechanical parts , gear, motor, etc should be properly calculated and sized.


As I have already (home)build a crane and a remote head for a 3CCD 1/3 inch cammera, that would do the job in an amator/hobby production but not in the proffesional one, I would like to know your oppinion on these specifications, especially if you have proffesional experience in the field. Also a "wish list" or "nice to have things" would be appreciated.

The market target would be probably the world of commercials, but not necesarely. I would appreciate any comment on this subbject.

I'm planning to finance and build a prototyp for myself, but I'm also interrested in selling it, so another issue is what would be an appropriate price for it(considering the other alternatives at the moment on the market). For sure it cannot be a bargain considerig the high cost for the high precision mechanical parts, but it would also probably not go so high as the alternatives on the market.

Thanks in advance,
Victor

 

[Nick Gardner]

Distance between tracks: 35 cm

It seems to me that that is way too narrow to be stable with an arm on it. Also, why not make it work on standard track? There is a ton of it around, and you wouldn't have to build it.

Just my 2 cents. Good luck and have fun.

Nick Gardner

 

[Levan Bakhia]

I would be interested in buying it. it is not the best question if you are interested in how much would we pay. it is better if you say, would you pay $$$ this much?!

:*) so count me as potential client if you make it.

 

[Manuel Wenger]

I´d also go for standard 62cm (2feet) track, it´s standard and for a crane a must to get enough stability. I´ll follow your development, altough i think it´s not an easy task if you want it really user friendly.

Think about following options which are common features for moco rigs:

- teach in functions, you don´t program keyframes, you teach the system via operating the head, crane, dolly,... this gives a more natural movement.
- learning one axis while playing back another, for example you recorded pan/tilt of your head, let it play back and while playing back your focus puller records the focus marks.
- move to scale, record with 1/2 or 1/4 speed, playback in normal speed
- triggering, you need something to tell the camera where the sync point of every single pass is, easiest with a bloop light, more convienient via a TC Generator.
- external trigger, so your MOCO system could start a model mover or thelike.

best regards to the North
Manuel

PM me if you have further questions

 

[vtrifu]

Thanks for your answers.

Nick, could you point me to a company that sells reliable, not very expensive tracks, eventualy also the matching wheels for the dolly to it?

 

[michael zaletel]

I would be interested. Remember to contact me once you have a working prototype.

-shooterr

 

[Nick Gardner]

Nick, could you point me to a company that sells reliable, not very expensive tracks, eventualy also the matching wheels for the dolly to it?

In the States Mathews Studio Equipment, in the EU Panther, Filmair is great but really expensive. Anyway you look at it it ain't cheap.

Wheels you could go a lot of different ways. It depends on if you have a geared drive system, a belt system, optically encoded drive wheel etc.

Nick

 

[vtrifu]

In the States Mathews Studio Equipment, in the EU Panther, Filmair is great but really expensive. Anyway you look at it it ain't cheap.

Wheels you could go a lot of different ways. It depends on if you have a geared drive system, a belt system, optically encoded drive wheel etc.

Nick

Thanks Nick,

I have already checked with Panther, they would sell 2m of high precision tracks for 2000 EUR . Besides that, I still have to fix a transmision belt in the middle of it, so I think it makes sense to build my own. I will definitly beat Panther on price with it. I'm thinking to make 2 versions of them, 35 and 62 cm, without and with the arm.

Any informations on how much would a "heavy loaded" Red weight? Zoom lens, rods, etc.

 

[assaffr]

How much budget have you actually allowed to build such a system?

 

[vtrifu]

Hi assaffr,

I will definitly invest as much as it's needed to make a proper product. If you have any wishes that such a system should fulfill, please let me know.

 

[John Pilgrim]

Wonder where Victor's project went...

I'm working on something similar: http://johnpilgrim.net/MoCo/