Time for a better video tracker.

[Horton]

The Ski-Doc Orbit is awesome and has become the gold standard slalom video tracking. Wakeye is also a very good product.

 

With either system, the problem is that they require a tight line to point the camera in the right direction. Even with a very tight line the tracker tends to point behind the skier at the ball as the rope gets shorter. If the skier has a little slack at the ball the problem gets worse. The standard solution is to keep the zoom pretty wide. The result is that it is just way better to have a human in the boat filming with a phone.

 

What if…. the system was designed so that when the rope is not pushing it the camera mechanically defaults to pointing out where the ball should be? If the line is somewhat slack the system wants to point the camera to the right or left instead of pointing at the last place the rope was tight. The result would be that the camera would track the skier with the line is tight and then go to the ball if tension is lost.

 

I admit I am struggling a little to describe the idea or think of a good analog. In the end the system can not be overly complicated.

 

[Mastercrafter]

Let me design and build it, and we'll be at least rich enough to buy boat gas this summer.

 

I already have it worked out in my head and will sketch it out this week, build it next week.

 

Good idea.

 

[Fastguy888]

I have explored some products but price has kept me away. https://soloshot.com/ is top of the digital tracking head game but $899. Might as well buy the totally autonomous drone https://shop.skydio.com/ for 2k. The https://pivo.ai/ looks promising but its dependent on a phone closer to $150. Would love to see one of these tried out for slalom. It would be cool to put on the boat transom and set it and forget it.

[dchristman]

How about this - use two stationary cameras and stitch the videos together. https://actionstitch.com/

 

[ScarletArrow]

I think it would be doable to design an oscillating camera mount the same way you would have for a fan. The trick is staring it at the right point, the speed of the oscillation and the amount of travel for different skier speeds and line lengths.

[klindy]

If there was some spring tension to keep the camera moving forward at the apex it would work. Instead of the rope rotating the camera forward, the rope would “hold it back”. Directly behind the boat a cam would ‘flip’ and the same thing happen on the other side of the boat.

 

If something comes out like this I claim the utility patent.

[dchristman]

@Fastguy888 Pivo Silver is in the impulse buy category at Verizon - $69 with free shipping https://www.verizon.com/products/pivo-pod-silver-fast-auto-tracking-smartphone-interactive-creation-pod/. Would have to come up with some kind of mount behind the pylon. It sure would be nice to mount it on a surface other than the pylon and be able to use a newer phone without OIS interfering... It's in my cart, but I only had one beer so far and I'm not checking out. Somebody else buy one and try it. If it works I'll be happy to pay full price.

[Horton]

i really think we are looking for a simple mechanical tweak not something complicated

[BrennanKMN]

I wouldn't think it would be too hard to drive a servo motor gear off some of the ZeroOff signals. That way you get timing right for all speeds.

 

CANBUS integration with ZO and a servo motor (or maybe stepper motor) driving the equivalent of a Ski-Doc.

[BraceMaker]

@klindy essentially a mount with a plate that acts like a cam would do it.

 

Towards the edges the cam would have a radius slightly tighter and then a stop at say just less than 90 degrees outwards.

 

A skier traveling outboard as they came off the rope the camera would keep tracking outwards till either the stop or the rope tension came back on.

 

The roller on the cam doesnt even need to be spring loaded just a lower durometer urethane so it compresses through centerline and expands afterwards

[Horton]

@BraceMaker exactly.

[mlange]

You guys are limiting your thinking to course skiing where you "know" where the skier should generally be from boat position in some way, shape or form. That doesn't help for video outside the course. The "stitch together" idea is an interesting one for that part of the problem.

[jpwhit]

Are you guys re-inventing the wheel here? Wakeye already has a feature for this issue on the later models. It's an adjustment that let's you offset the pivot point of the camera from the center point of the pylon. That basically causes the swing angle of the camera to be non-linear relative to the rope angle. Said in another way, as the angle of the rope gets greater when the skier is out near the ball, the camera angle is even larger, meaning the camera turns even further towards the buoy.

 

I understand it's a little different than making the mount spring loaded, but it solves the same problem and I make heavy use of it since the goal of my camera setup was to be able to zoom in well on the skier. I do think the spring loaded idea does have some merit, but it will also introduce an unusual camera movement as the mechanism "snaps over" as the skier crosses the center-line. I worry that will be problematic since watching for stack as the skier is behind the boat is fairly important.

 

I also have a ski-doc, and I tried it out because I do think the ski-doc is much more durable. But I ended up going back to the Wakeye specifically due to this one feature.

 

 

 

 

[swbca]

Remember the 8" long toy cars that had a flywheel that you would energize buy pushing the car forward fast, then the flywheel would propel the car for a while.

 

Many Hybrid cars store energy in a very high rpm flywheel during breaking to reuse during acceleration . . . in some cases without a battery. Same could apply to a pylon camera mount.

 

The camera would continue to advance forward with slack and the rotational jerk would be dampened when the slack finally goes tight after the turn on short line.

 

A flywheel would energize the desired movement and dampen the unwanted movement, but it would have to be engineered to withstand the extreme rotational force of dampening rotation when the force of a slack rope applied to its internal gearing which would be 1:100rpm at the flywheel. The hardest part is the axis of the flywheel would have to be offset from the axis of the camera mount, so a mechanical gear or chain drive linkage would have to interconnect.

 

There would more room for innovation if there were more of us to pay for it.

[jpwhit]

It's also worth noting that the optional shock tube arm on the Wakeye works much better than the default arm that just the rope passes through. It's also significantly more durable.

[Splasheye]

@horton if you're ruling out complicated solutions then I had better give up!!

 

These projects on my desk a long time - just need some finishing.....

 

 

Servo driven camera. GPS Start/Stop. 60 fps. Computer vision tracks the skier in software in realtime and controls the camera tracking.

 

 

 

 

Three cameras, all 60fps, one looking at each side and one in the middle. Software stitches the video together based on GPS course start. Good zoom lens. GPS Start/Stop recording. WiFi based system for realtime scoring in competition

 

Sometime in the next few years maybe.............

[UWSkier]

I'd do this with a cam setup and a single roller on a spring loaded axle. Cam would be flat from what would effectively be trough to trough and gradually increase in angle until it ended at 80 degrees off centerline (cam would transition back to flat but camera could still rotate past that). It would be symmetrical on the other side. You could retrofit this to a ski-doc easily. If I had a 3D printer, I'd design and build one to try out.

[Horton]

@jpwhit I really love that product but it still could be improved for shorter rope lengths.

[disland]

maybe with such high definition cameras they have today a stationary camera with a wide angle lens and you zoom in on the skier in post production

[Horton]

@disland

[RazorRoss3]

I think the real solution is @horton needs to make some friends so he can always have a video spotter and to put that lake off his to good use.

[VONMAN]

@Horton you need a camera person in the boat. This only way to get good close action video and stills. My setup for the last twenty years has been a Canon reflex camera with a hood for shooting video and a BushHawk hand/shoulder brace. Works great and you can do in the boat reviews.

 

[RGilmore]

The inventors of the first waterskier-path camera-tracking system - named "Trakker" - "solved" this problem with an advanced model they marketed. It used a series of toothed belts and pulleys, plus a flywheel, to maintained the outbound rhythm if/when the rope went slack. That was a couple of decades ago, and if I looked around my garage long enough I could probably find the damn thing. It actually worked... to a certain extent.

 

Anyway, I said that to say this: Ecclesiastes 1:9

 

As always, IMO

[Horton]

@VONMAN You completely missed the point.

 

[VONMAN]

@Horton Thanks, I will accept the Badge of Honor. The Triple Panda!

[Horton]

@VONMAN not saying your set up isn't kind of awesome just saying it's completely impractical for most of us and not what this threat is about

[disland]

wow, I never got a panda before, is that like PB?

[Cnewbert]

There are some AI powered dynamic motion video tracking cameras and smart phone camera mounts already on the market. Obsbot is one I ran across and they offer both a 4k tracking video camera as well as a smart phone tracking mount. They’re pretty interesting, though since I don’t have one I can’t say if they are fully equal to the task just yet. But this one (Obsbot smart phone mount) does appear capable of tracking a person running back and forth in front of a smart phone at least. Even if they’re not quite ready for prime time, it may not be long before higher performance models are on the market and capable of tracking the speed of a skier crossing the wake. There are a number of video demos of these in action and worth a look, at least to see what the potential is.

[Cnewbert]

BTW, I’m guessing one could use a GoPro with the Obsbot tracking mount as well. I don’t think the camera matters. The mount itself employs a camera and combined with AI and a fast responding brushless motor, it apparently locks onto the face of the person being tracked and follows it both horizontally side to side as well as varying distances from the camera. Again, I think the system has real possibilities — if not yet at present, certainly in future generations. And they’re cheap!

[BraceMaker]

The digital method should just be a camera with a wide enough lens angle that is programed based on some output from ZO or sure path to track. If either company just sold a mount that could be put on the pylon, bimini, a tower or the dash that used input from the position of the boat and pointed to the bouy at every point in the course I am sure they will sell a number.

 

Since the post about a flat cam that has a profile that encourages the camera to point "outwards" of center I then refined this to have a track plate beneath the camera onto which a roller bearing was pressed.

 

This cam would have a smoot hump being low at an angle approximating the bouy angles of shortline skiers as well as a slight valley behind the boat to the effect that there would be a desire for the camera to point rearwards or to the extremes.

 

2 parallel plates would be mounted such that a thrust bearing between them held them concentric and then one plate would hold a roller bearing on a shaft and the other plate would be the tracking plate that would have a slope of whatever degree was required to overpower the wind drag slack that would point a rope rearwards.

 

 

[OTF]

You know what works really good?

 

A person holding a camera

[skialex]

@OTF a thin person preferably….

[OTF]

Depends on how fat the driver is

[Horton]

ballast can be moved

[BraceMaker]

@OTF you know it works but it isn't that good - just when you get back into the boat after a crash and go - did you get that on tape you'll get a blank look and the person put the camera down when they got bored.

[OTF]

@BraceMaker

True, that happens most of the time.

 

If you can’t drive you’re the camera guy

 

If you can’t film you better be the driver

 

If you can’t drive or film you better crash hard every set so I can film it and laugh over and over and over

 

If you’re none of the 3 then we can’t be friends

[OTF]

That’s why I @The_MS so much

 

He could drive

 

He could film

 

He doesn’t crash often but when he does ITS GLORIOUS!!!

[skialex]

So this is an area where humans are still better than AI or any kind of a device. Enjoy people, soon it will be some brilliant device that will do this better, but not at there yet…

[Horton]

a person with a cell phone will always be the best at this task