Moving Fountain

[ThemeParkPenguin]

Hey Guys! I'm new to Control Booth and this will be my first post. Sorry if I put this in the wrong section, I'm still trying to figure my way around here.

So, I am making a fountain show and would like to have an electric motor to rotate some of my fountains. However, I would like this to be controllable via DMX Interface timeline. The elements I would need to control would be, speed and direction. How could I hook up a typical electric motor to a DMX Interface or what can I do to alter a normal motor so it is compatible.

Here is a video of what I want to make: YouTube - Moving Fountain test

Thanks!

 

[mstaylor]

So what you are asking is how to turn motors on and off. You are using them to rotate the fountains, what size motors? I believe you can use a DMX controlled relay to turn it on and off. You could also use a timecode or music sensitive program to control the DMX.
Welcome to the board. Stop by the new member board if you have a chance.

 

[ThemeParkPenguin]

So what you are asking is how to turn motors on and off. You are using them to rotate the fountains, what size motors? I believe you can use a DMX controlled relay to turn it on and off. You could also use a timecode or music sensitive program to control the DMX.
Welcome to the board. Stop by the new member board if you have a chance.

Basically, all I need to have control over is

1) When they're on/off
2) What direction there moving
3) Their speed

 

[FatherMurphy]

Control over on/off is easy, the aforementioned DMX relays. Speed/Direction are more complex. A regular, garden-variety single phase AC motor tends to be single direction, single speed. Some additional wiring and cost can give you reversible, but still single speed. Moving to three phase AC motors, along with phase adjusting electronics, will give you control over speed and direction ('off' being zero speed at that point).

DC motors are a bit easier to deal with, since you just have to vary voltage to adjust speed, and polarity to change direction. A variac type dimmer with a rectifier, plus a relay to change polarity, and you'd be ready to go. However, finding a DMX-controlled variac might be a challenge, and I don't think SSR/SCR type dimmers would be happy for very long with an inductive motor load. The newer sine-wave dimmers might be a possibility.

If the video you linked is what you're trying to achieve, you might think about hydraulics instead of motors. There's plenty of flow control valves available that run on 0-10 vdc analog, which is an easy decode from DMX, plus you'd be able to remote everything electric well away from the water, reducing shock hazard to almost nil. Compressed air actuators might also be worth a look.

You might search around for 'show control' type topics, making motors run forwards and backwards at different speeds is also what people are doing with moving scenery winches.

Most of the water shows I've seen have used the water pressure itself to provide power for movement, the rocking action in the video could from be a turbine-type impeller shaft, geared down, with a connecting rod to the water jet bar. The 0-10 vdc flow control valves and a dmx to analog decoder would then be all you need.

 

[TheDonkey]

I'm not sure what sort of budget you have, but the most DIY option would be to use a stepper motor salvaged from an old printer (thrift store) and an Arduino with a stepper motor shield.

A printer can be had for $10,
Arduino clone + motor shield would be ~$30-40
You can order a "Sample" RS485 (DMX) transciever chip from MaximIC for free (Or purchase one for around $5)

Add $10-15 for various DMX jacks+enclosures and you have your electronics. You would have to come up with a way to either run a belt between motor and nozzle or isolate everything.

And there's lots of sample code depending on how complex you'd want it to be.

The easiest way to write the code would be to have DMX 128 stand for No movement, 129 and up rotates clockwise, 127 and down rotates counterclockwise.
But that wouldn't fit into your plan to timeline everything because you'll pribably get sync issues.

The harder way would be to add end-sensors to the two extremes of the motion for your nozzles, count the steps in between. Then write code so that when you turn the arduino on, it turns the motors one way until it gets to the stop then counts back the steps to center itself. Then you can map out DMX values to locations between the two stops. (This is essentially what professional fixtures do)

It would probably take about 2-3 hours to assemble the hardware if you knwo how to solder, and 4-5 hours to get all the software properly written up. What's nice about the arduino is that there are already tutorials and code written for accepting DMX and for controlling steppers, so you'll just have to figure out how to make the two work together and the math for DMX values > Steps.

 

[Van]

You could also check out these guys
Musical Fountains
They sell some " Leapfrog" kits for DIY. Again it really depends on your budget. you can buy valves, solenoids, an other fountain controllers type things at many Fountain shops, the real question as above is leel of control and if you want to build your own Arduino based interface, or if you can get by with a DMX relay control system.

 

[What Rigger?]

Or .....you could get nuts like these guys with their huge budgets.
YouTube - World of Color: Lighting, Fire and Animation