The robotic floating course

[andjules]

A few months back we had some threads on innovative ideas for slalom courses.

 

I was leafing through the latest issue of Wired and saw that Berkeley is experimenting with autonomous, GPS (recycled cell-phone) based water sensors. One step closer to the dream of an affordable, portable course, where you throw individual buoys out of the boat and they put - and keep - themselves in the right spot.

 

http://wsnblog.files.wordpress.com/2012/05/float-diagram.png?w=300&h=268

http://d3uifzcxlzuvqz.cloudfront.net/images/stories/content/projects/float/float.png

Berkeley's floating sensor network

[Ed_Obermeier]

Any info on cost per sensor/buoy?

[andjules]

well, it's just an experimental program right now.

But they mention using recycled Android phones (we'd need an android unit with a better gps for accuracy, though these are getting cheaper and more affordable all the time) and they're clearly using standard water filter housings. I can't imagine the little motors/props are too hard to find in the electronics-project-parts world. So I think the only expensive/laborious part is custom mouldings to fill out the case housing (and, of course, the programming). A long way to go, for sure, but we're getting closer... and interesting that they're programming with Android, which is a pretty accessible platform.

[SkiJay]

How cool would it be to dump a box full of something like these (with soft tops) over the side of your boat then watch them spread out into a perfect course all by themselves wherever you happen to be?!!!

[dtm8119]

A little bit of an old thread, but I found this while googling around tonight.

 

http://www.freepatentsonline.com/y2010/0087110.html

 

Wonder when something like this could be on the market?

[MattP]

@dtm8119 I hate reading patents, but that looks way to complicated. I like the one @andjules posted and could be adapted to a course pretty easy with a more accurate GPS unit.

[mwetskier]

that patent application is listed as abandoned in 2011 at least thats the info i found with that number

[Lucas]

I don't like the chances of the gate buoys being able to stay in the same spot after the boat has gone through

[BraceMaker]

If the unit was actually more of a sub bouy with a ball over it you would have an easier go of it.

[Horton]

Ballers are geeks

[A_B]

Pretty cool. Just think of how it would operate ona certain lake in MN......

[Brady]

what @AB said. Probably would make less wake as it moved in for his sets

[ral]

As stated by @AB, instead of Dr. M. pulley system, we could use hackers in the future.

[Skihack]

I am not a jumper but a Slalom freak, but I could see where if this could be done with Ski Jumps on public lakes the sport of waterskiing would literally just boom with tournament participants. Accessibility to ski courses and jumps have killed the participation in tournament skiing thus turning it into an elite sport. This could be the boost the sport needs.

[MattP]

I think it could work for all the buoys on a slalom course except for the entrance gates that's might get displaced to easily by the boat wake. (Referring to the single units)

[6balls]

Would be very interesting for the public lake set for use 'em and pull 'em...especially if there was some sort of quick mapping function to re-locate it. Some days one shore is smooth, some days another based on wind. Sucks to have to move a course or pull it and re-install. If could simply plug in the coordinates, dump 'em out of a john boat and sip some coffee while they set up that would be really cool. Pull 'em when done and drop back in whenever you want to ski. Could be cool...little solar panels on top?

[mwetskier]

have a little buoy garage for them right on the water and just tell them to go home when your done skiing. next ski day you can deploy them from the same garage while your putting on your gear

[danbirch]

Just don't hit the buoy with your leg, or the propeller might hurt.

[Wish]

@AB, did you mean Michigan? The Doc with the funny moving buoys was not from MN. Hate to see MN get a bad name.... oh wait, I dont live there anymore and @MS does.. Never mind, continue jabs as normal.

[Ed_Obermeier]

Fun to talk about, cool in theory, unworkable in reality.

[Steven_Haines]

Solar

[MattP]

@Ed you don't know until you try. Are you talking about the pods or the patent design?

[Ed_Obermeier]

I'm talking practicality. These things would have to work their tails off in constantly moving water (boat wakes) to hold position. That requires a lot of battery power and fairly stout propeller action and control. Battery life would be a huge issue as would maintainance cost over time. To work properly they'd need to be a couple feet below the surface holding the buoy in place so solar isn't an option. Cost per unit would likely be prohibitive. Don't misunderstand me, I think the concept is cool as hell and if practical could be a game changer. Hell I'd buy it myself assuming it wasn't cost prohibitive, which it would likely be. The tech just isn't there IMO and if it were the cost would make it a non starter. Super cool idea; just trying to keep it real.

[Bulldog]

It would be amazing If they were able to recharge with solar power.

[SkiJay]

Solar pannels don't work well under water and would be terrible to ski into above water. However, Robi vacum cleaners return themselves to a basestation for storage and recharging. This could be done with a ba$e$tation $porting a $olar array anchored be$ide the cour$e.

[SkiJay]

I love this concept, but there are a lot of downsides. Cost is a major barrier, but there are also safety, size and handling issues. 26 of these babies might fit into a tournament boat, but they would likely be hard on the gunwales and upholstery. The weight of the battery and propulsion system alone would make them heavy and awkward to move around. Skiing into one would suck; the mechanics would all have to float deep enough below the surface that they can't be hit, making them even bigger and more awkward to handle. And while cleaning the slime off of 26 balls is somewhat optional, keeping these expensive robo-buoys slime-free would be mandatory. The only hope of these dream buoys being developed is if the US military decides they need rapid deployment stealth slalom courses ...

[ksu_skier]

I think another issue to get into would be how accurate the gps units would have to be on each of these (especially if you're looking at using these in tourneys with record-capable skiers). Currently, cell phone gps's accuracy is nowhere near close enough to get buoys set correctly [with error margins over a meter]. Even standalone gps units' accuracy can't beat a meter.

[BraceMaker]

@AB @Wish - you're both wrong - He's up in WI from one of those towns that you can only pronounce if you are from WI.

 

https://maps.google.com/maps?q=43.005165,+-88.472064&num=1&t=h&vpsrc=0&ie=UTF8&ll=43.004318,-88.470755&spn=0.009023,0.01929&z=16&iwloc=A

 

Its one of those magical areas where if you start to zoom in you start finding ski lakes.

[MattP]

@ksu_skier I would not use them for tournament use.. just practice on bodys of water that dont have the ability to put a course in.

[FrankS]

@BraceMaker yup that is his lake. I have skied there before. As for the buoys, they would be a dream come true for me as I live on a public lake and setting up a course every time you go out isn't always fun or time efficient. For it to be practical it would have to have a soft top and an insane battery life for adjusting when wind pushed them. I doubt that a gps which is small enough to be practical in something like this could adjust to the exact measurements of a slalom course as fast and frequently as would be required in order to have a decent course.

 

[BraceMaker]

Same problems as @franks but its not the time - its finding a crew who doesn't bone you, like leaving the boat in gear such that you have to let go of the mainline (or get pulled off the platform while trying to step over the boom as it plays out.

 

But I think we'll see a goggle heads up display based ski course before we ski a self deploying physical course of any substance.

 

 

[EricW]

We should get Zero Off to allow programing of the boat path and have an auto steering retrofit for your boat so you could do away with the boat guide bouys.

[UWSkier]

I'd say @BraceMaker called it in his last line...

[Mateo_Vargas]

My buddy has a patent on a GPS controlled buoy and a working prototype. He's just waiting now for the technology costs to come down. A hybrid system where the driver uses the HUD to see the boat guides and the skier goes around real GPS buoys might get the costs down.

[UWSkier]

Problem is GPS isn't accurate enough. Need something like a drone swarm control algorithm and RF triangulation. That and the robo-buoys need to be able to anchor in place.

[JAG]

@SkiJay

"How cool would it be to dump a box full of something like these (with soft tops) over the side of your boat then watch them spread out into a perfect course all by themselves wherever you happen to be?!!!"

 

After trying to raise our course this past weekend, removing hundreds of pounds of weeds, ripping our hands to shreds, and then being too tired to ski, this would be better than a date with (insert hot supermodel's name here).

[UWSkier]

@Mark_Matis are you speaking of differential GPS? For that, you'd need fixed, ground-based stations and even then, the resolution is about 1m, which I'd argue is too far out of range for a slalom course.

 

There is some new research published with IEEE last year that simplifies the mathematical rectification of GPS and IMU (intertial measurement unit) to the point that something like a smartphone can do the math. This will take GPS accuracy down to an inch or less resolution. This relies on devices being kitted with an IMU and a smart-watch worth of processor power.

 

The applications for ultra accuracy are driverless cars, which will be good since that will give the technology the scale to eventually drive down costs.

 

So, the dream of a self-deploying slalom course, from an accuracy and cost-feasibility perspective is probably a good 5-10 years away. Unless you want to get lasers involved... :)

[UWSkier]

ZO is a completely different application entirely. It has the benefit of motion and a rapid refresh rate to approximate location pretty accurately, but even that is likely a meter or so off at any given point. It's nowhere close to the accuracy a self-deploying course would require. Take a manual timing with a ZO pass for instance. At 36 MPH, a boat is traveling 16.09 meters per second. If your tolerance between a fast and slow pass is 0.3 seconds, that equates to requiring GPS accuracy of 4.8 meters or better if you never have an out-of-tolerance pass. ZO is is clearly a very accurate system, but not accurate enough for buoy placement.

 

Say you have a "Master" buoy that serves as a reference to all the other buoys and they each know how far apart from the other buoys they're supposed to be. If each has its own GPS receiver that is only accurate to a few meters (current standalone GPS) or one meter (GPS augmented from shore-based, fixed stations), each buoy will have its own interpretation of where it's supposed to be, and it'll sit and wander around within its range of accuracy. Put another way, just try to deploy a set of boat guides. If each guide buoy can move around a meter yet still think it's in-line, how's that going to work out?

 

Now, the newer technology that's accurate down to a cm or two... that's a different story, but it's not available yet for hand-held-sized technology.

[david_quail]

Doing my Ph.D. in artificial intelligence. We taught a helicopter drone to do areal stunts that expert pilots can't even do. I suspect a robotic buoy could be taught how to stay within a 1 foot radius of a center spot relatively easily.

Actually, it'd be fine if the wake threw it off a few feet. So long as it navigated itself back to the starting position before the next pass.

The new version of blue tooth should allow each to communicate with each other and communicate accurately its precise location. This is good since you could bipass gps ... Which is way more expensive on the battery. I feel like these could be so easy to deploy that taking them in and out of the water after each set would be fine. 30 minutes of battery is enough to get your ski in. My dji phantom can last 10 minutes of flying on its battery, so I suspect a robotic buoy could easily last 30 minutes

 

Perhaps it's not quite there yet ... These things are always way more complicated once you start getting into the nitty gritty. and perhaps it will never be as accurate as a permanent course, but I don't see anything from the tech that makes this impossible in the near future.

[UWSkier]

@david_quail exactly my point. Using RF positioning instead of GPS would increase accuracy. Something like the control algorithm used in drone swarms like employed during the superbowl halftime show could easily accomplish this since the buoys can only move in two dimensions. Your work sounds really cool btw. :)

 

I've been researching this topic for a while with some roboticists. Didn't realize there was already a thread about it until I bumped this one.

[OldboyII]

May be will it have a sense to make master buoy on separate platform floating (or anchored) aside of course equipped with bigger energy source?

(Did not read all posts, sorry if already said)

[Sethro]

Any updates on this idea? I'll be waiting in line when this hits the market as a reliable alternative.

[andjules]

One development since the original discussion: Broadcom's L5 GPS chip has made its way into the Xiaomi Mi 8 smartphone, with some hope that the next round of Samsung phones may also incorporate it. It's the first time we've had 30cm/1' GPS accuracy in a consumer smartphone.