PLC Veracity Control Wheel System

[Alan Rencher]

I don't know if anyone noticed this, but PLC Electronics has come out with wheels that will work with RC controllers for gimbals like Movi. It looks like we'll soon be getting better performance from professional operators with these systems.

 

http://veracitycontrolwheels.com/

 

http://www.plcelectronicsolutions.com/categories/veracity-control-wheels/?sort=pricedesc

[Afton Grant]

Anybody else find it amusing the wheels are being used backwards in the demo video?

[Thomas English]

I wonder how these things work. I was under the impression there was no rotary encoded feedback on the Movi / Ronin.

 

I owned a Jimmy Jib a few years ago and had the wheels setup for that. It was not... accurate.

[Mike Johnson]

Hello. Mike Johnson here, co designer of the veracity wheels. Our system creates a digital data stream that is read by RC transmitter. The RC transmitter (such as a Spectrum8 that ships with the MOVI) can be configured to substitute the joystick signals with the digital stream that our wheels create. This is connected in the RC trainer port. The accuracy and feedback of the gimbal rig is not affected by the wheels. The gimbals are typically as accurate as the sensor modules they use. Another factor is system latency. Different RC transmitters have different latencies. Some as low as 10ms, but many much higher. Our wheels add no latency to the system as all the processing happens inside the single data package heartbeat time frame.

 

The jimmy jib as I know it (aka Staunton triangle jib has no feedback whatsoever. It runs open loop and uses a slip clutch to mechanically limit damage. This is makes it low cost at a sacrifice for motion quality

[Steve Acheson]

here is same system for way less...

 

http://cinescopophilia.com/hurricane-wheels-brushless-gimbal-interface-allows-for-the-use-of-hotgears/

 

and then you can take and connect them to computer and use their software to practice your gear head skills...

 

Plus it 3 axis

[Iain Baird]

here is same system for way less...

 

http://cinescopophilia.com/hurricane-wheels-brushless-gimbal-interface-allows-for-the-use-of-hotgears/

 

and then you can take and connect them to computer and use their software to practice your gear head skills...

 

Plus it 3 axis

 

This may be a device designed around the same principle but I hardly think it's fair to call it "The SAME system for way less" unless you've tried them both and can attest to the quality of each.

 

There are many Steadicam systems that cost WAY less than what I own, I would't say they are anywhere near the same though, as there are many focus systems that cost WAY less than what I own, and again ...... well you get the picture.

 

just my 2 cents,

 

 

IB

[Alan Rencher]

I think the hurricane wheels were designed originally to connect to a computer for the purpose practicing operating a gearhead at home. I think it was only recently that they made an interface module to use them with a gimbal. To say they are the "same system for way less" seems kind of insulting to the people who have spent so much time, energy, and money developing the Veracity.

 

Not to go on a rant, but it seems like people forget how small this market is. Most of these companies are very small, and you could call and talk to the people behind the products in length about them. To simply dismiss something they worked so passionately on before ever using it or even talking to them about doesn't help anyone. I think these kinds of threads should be more constructive than dismissive. </rant>

 

No back to the thread!

 

I talked with marc at PLC about the Veracity controls today, and he mentioned that a lot of attention to detail went into this product from custom machined wheels, to high resolution encoders, to high quality gears and drag adjustment. I want to try it before I dismiss it.

[Steve Acheson]

Sorry wasn't trying to insult anyone who produced the product. Please forgive. Just trying to say that they are not the only game in town. Next just because something is cheaper doesnt mean that it is not worth the money or does not work. Looking at both videos they both look like they preform the task they are designed to do.

I own 2 bartech systems which cost WAY less then a preston system and my bartech works just fine and hasnt failed me yet...

 

Here is another system that is out there...

http://www.radiantimages.com/stabilizers/871-geared-movi

 

Not trying to start huge battle here or start the crap talking just pointing out something... Now yes there plenty of knock offs and piece of crap systems out there that are not worth the money. But just because something is cheaper doesnt mean you should dismiss it. If so we should dismiss the movi compared to other stabilized remote heads out there.

[Mike Johnson]

There is no question that an encoder to RC interface can be made cheaper and still sort of work. Arduino and plywood are your friends if that is the road you are travelling.

 

When I was doing the mechanical design of the Veracity wheels, I opted for precision and ruggedness over ultimate cheapness. By having hand wheels CNC machined instead of off the shelf Milling machine wheels does increase the cost, but provides a better feel and familiarity to operators used to heads like Libra or Scorpio. Adding in adjustable balance counterweights also adds to the cost, but allows perfect balance every time, as well as a 'feel' of inertial mass that allows the wheels to better mimic a traditional geared head.

 

I think it is important to remember that there are plenty of gimbal operators out there that will find the RC joystick to be perfectly acceptable for operating. But for operators who want to retain creative control over gimbal shots and who do not not find the RC joystick suitable, then the feel and quality of the interface should not be discounted. it is after all the point of sale terminal, so as to speak...;)

That was the design philosophy that I embraced when I made a lot of the decisions regarding the Veracity wheels.

[Thomas English]

Dear Mike,

 

Thanks for taking the time to respond on this forum. The film industry is full of price points and the best product tends to become industry standard based on quality and reliability irrespective of price. Most of the people requesting kit (crew) in our industry are not the ones paying for it. Hence you are doing the right thing striving for quality.

 

So my question with regards to accuracy. Is a 1/5th of a wheel turn equal to a specific amount of camera movement? The Jimmy jib wheels where kind of kinetic in the dimmension. So if I do two turns upwards then back down two identical turns will the camera be in exactly the same place?

 

Best Regards

 

Thomas

[Mike Johnson]

I understand your question. In order to maintain exact wheel to head motion relationships, there needs to be direct feed back on the head. High end equipment like a Libra head have stiff drive trains and position feedback generated by encoders or resolvers mounted that is accurate to the movement of the camera. As a result they can be expected to track a tight relationship between movement of the hand wheel and movement of the camera.

 

In the case of the jimmy jib there is no feedback at all. The amps are tuned to move by some arbitrary ratio of the hand wheels. However if there is slippage, or imbalance in the load due to camera CofG or wind or any other external effect, then the camera moves differently. The controller has no idea where the camera position is or how fast or far it is moving. THis design works because there is a torque limiting clutch in each axis. There can never me precise control in an open loop control system.

 

In the case of the Movi and other gimbals, there is no direct camera axis postion feedback. Camera position is not controlled by encoders mounted on the camera axis. Instead it is generated by a three axis gyro. This provides velocity and acceleration information but not position. These gimbals work to control camera velocity, but they have only the earth gravity reference of the sensor. This is used to control horizon, but there is no information generated that can allow the system to track position in the way you describe. The same is true of a PowerPod which uses Tacho generator voltages as feed back. In that case the controller knows only how fast the axis is moving and not where it is.

 

If you want a precise wheel to camera axis relationship to be maintained, then you must look to a system that uses a closed loop servo system with encoder or resolver feed back directly mounted in the individual axis drive train of the head. This makes for a higher cost and heavier system then the movi style gimbal or the jimmy jib, but the digital controls and the stiff drive trains that are typical of higher end camera mounts allow them to provide that exact precision coupling between wheel and camera that you mention.....

 

I hope that helps

[Thomas English]

Thanks. That helps a lot. So your wheels system is a vast improvement on a jimmy jib but not all the way to a remote head in accuracy. The proof will be in the pudding so looking forward to trying it.

[chris bangma]

The libra head ran for many years with gyro only feedback, and it was accurate. If you keep all the timings correct, you can have a head that is quite repeatable, despite not having direct feedback.

[John Buzz Moyer]

Mike,

How much does your system depend on "window" and speed settings on the movi interface. Does your system have

Independent dampening and speed controls that override the Movi settings or do they work in tandem like the current Hot

Gear interface?

[Mike Johnson]

"Window", being deadband, is not an issue for our system. We have a 'zero' button that allows the wheels to be offset to the zero reading of the rc transmitter being used, so the Movi window will not need additional adjustment. As for speed control, we have a sensitivity knob on each wheel that scales the wheel output. If used with a movi, then the movi software setting would be in tandem, but I just set the movi full speed and adjust on the wheels. As for damping, we offer none except the additional mass of the internal counter weights. My experience with the Movi and its gyro feedback, coupled with the RC radio latency of the transmitter, additional damping is not particularly desirable. The remote movi interface be it via RC joystick or with any wheels plugging into an RC transmitter is not super tightly coupled. So adding extra de coupling to soften the wheel response is not necessary. Also consider that the Movi will top out in the 35-50mm lens range and dampening is a feature of long len work....