Intelligent Ski-Course

[chris_logan]

If this is already old news, just slap me, but I saw this link floating around on facebook this morning and found it to be quite interesting. I wanted to post a link to it here to see what other ballers' opinions would be on it:

 

Intelligent Ski-Course

 

I can see some obvious logistical issues with it, like safety and accuracy, but at least somebody out there had the gumption to organize their entire theory and plans, in what appears an open capability to allow others to build on those plans and perfect the system.

[oldjeep]

Interesting, you would definitely need water with absolutely no weeds in it if he can work out the rest.

[Texas6]

Fantastic idea, but I hope its not an exercise in futility: just seems like those things will be adjusting themselves the enitre time they are in the water to stay in place properly killing any battery life expectations and then your intelligent course will be far less intelligent

[mlange]

He did mention the addition of solar recharging. Not sure if enough sun could get down to where the "brains" of each buoy are below the surface to keep it charged because definitely those motors would always be running to keep each buoy in place.

 

And how close can GPS get nowadays? Is it good enough to keep the buoys within an acceptable tolerance?

 

At the $50/buoy price point you'd be looking at $1300. Pricey, but for people like me that ski for a couple of hours in the early morning with a few other boats on a public lake where we can't put a permanent course in... I'd be all over this.

 

 

[oldjeep]

$1300 is inline with current portable course pricing

[sunperch]

For some reason, this had me thinking of Dr. Jim Michaels...........can the coordinates be changed for each contestant bouy?

[chris_logan]

@sunperch I'm thinking this would only have practical application with those ballers who ski on public water with traffic (wallys pulling tubes, fisherman, pwc's). I don't see any practical tournament application with this system.

[gsm_peter]

Would love to have one.

Guess it has to be costly to be durable and exact enough.

Also a small market will put it in more likely 500 per boie.

Share with a group guess the limit would be typ 5000 usd for full course

[Mateo_Vargas]

One of my boat partners has a GPS buoy built and I believe patent pending. His design will have no issues with weeds. I'll talk to him tomorrow to see if he is ready to reveal it.

[sunperch]

@chris_logan‌ that was a joke, LOL.

[kfennell]

1. GPS has ~ 1M accuracy in this application, the steadiest I've ever seen my drone stay without any wind (and it is a VERY VERY good drone is about .25M)

2. The batery life fighting against the waves would be awful.

3. Definately the cost would be about $100 per buoy to make any money I expect

4. I think you run into a problem where you need a bigger battery verey quickly, but moving a battery through water isnt very effecient so you need a bigger battery but then its less effecient etc etc etc very quickly.

[ricski39]

My initial thought on this was, "Wow, the future is here!"

My very next thought was, "I hope your driver isn't prone to hitting any buoys..."

[crashman]

I tend to agree with @kfennell‌ but then again I thought text messaging was a stupid idea that would never catch on

[Fine409]

Put me in the camp of someone who would love to have something like this.

 

Living on public water (smaller lake - 190 acres) where it would be tough to get a permit to have a permanent course in year round and not have to deal with the hassle of putting up a portable each time, this would be pretty slick.

[kfennell]

@crashman It isn't a bad idea at all, its a teriffic idea, unfortunately I think that it is an idea that is 5 years out. It will require a tripling in battery power and the release of the Galileo high resolution satellite system. At that time a system like this would be awesome!

[E_T]

Solar panel ball... Problem solved

[kfennell]

@E_T nope, not even close, even assuming the balls have a square foot of area that is only 8-10W they are making and only in the day. I would estimate that position holding would take closer to 50-100W. Especially during use.

[Wish]

What if they moved into place and dropped a small weight to hold themselves in place to reduce battery usage. Small spool, heavy gauge fishing line.

[Than_Bogan]

@kfennel Now I think it is you who are too optimistic! We've been trying to get a substantial increase in battery power for about 100 years and it's been VERY slow going. A tripling of battery power will almost definitely not occur during my lifetime.

 

However, there may be other ways. Wish has a nice idea, especially for shallow water. Or power 'em with a combustion engine! Doesn't have to be gasoline, could be more like model train engines. Or some kind of solid fuel pellet might be more convenient. Anyhow, it doesn't seem crazy to me to think the user has to refuel them in some way before each use.

 

All that said, this particular idea might be a bit over the top. Still, would be fun as hell to work on!

[kfennell]

@than_bogan I suspect that more research is being done each year on battery technology right now then in all of the years previously in history? There are a number of promising technologies in the works right now including lithium anodes (I think it was the anode, I forget) that could result in an increase, or maybe someone develops a better capacitor?

 

Anyways you still could be right, but I hope you're wrong, imagine a fleet of drones 3d printing your next house.... and other such possibilities that can come from better battery power.

 

 

[Ilivetoski]

GPS is accurate to within 16 feet. If you look at disclaimers on big GPS companies (iPhone apps, Garmin, TomTom) they all say "accurate to 16 feet". Someone that I know has a consultant for Zero Off as a patient and they had said that they had worked on a boat that keeps its own boat path but the GPS accuracy is not there yet.

[Waternut]

@wish beat me to the punch. Dropping a weight once in place would be the solution to random waves during skiing.

 

I'm gonna geek out a little bit so bare with me.... If GPS is so inaccurate, how is PP and ZO able to get acceptable times based on a no magnet course? At 36mph passing a random point in space, a 16 foot accuracy limit would mean a potential 0.3 second margin of error at each timing check. It's about 0.33 seconds at 34mph. Yet +/- 0.05 seconds seems to be the new acceptable limit which equates to about 5 feet over an 850 foot course. Although if you use the gates to first buoy as the restricting number, you need 1.68 seconds (+/- 0.03) which means that the accuracy would have to be at worst, 3 feet.

 

So yes, it'll make a difference in the course accuracy but if I could have a course to ski on at my own lake in 5-10 minutes, I would pay $2k for that. I would still go to a real slalom course as well but it would be better practice than just doing open water skiing.

[Than_Bogan]

ZO "cheats" wih an accelerometer for high frequency correction. Also velocity is more accurate than position with current GPS. Still I think 16 ft is kind of a worst case. ZO usually beeps very near the entrance gate for example.

[jaredH20]

I am friends with the guy who is designing the course. The footage supplied is from my brother.

 

At the moment the bouys are going to cost $40-50USD each, but this is at the prototype stage. He envisions the final cost being half of this. While there are many factors that will certainly be hard to overcome I have no doubt someone as dedicated as this can do it.

[GregHind]

GPS accuracy probably isn't a problem. Differential GPS can take care of that.

 

For example a "buoy" sitting still on the bank can calculate the changing errors in the gps signal and tell the others what the current error is so they just take it into account. Worst case is the whole course, as one unit, might move a few feet from day to day BUT it should be possible to get the dimensions accurate if the drones can do it.

[Than_Bogan]

@GregHind. Good idea! That's much more elegant than what I was thinking of, which is to have each buoy broadcast an IDed signal, and then the buoys can determine (and then maintain) their position relative to each other by triangulation.

 

The inventor may have an even better idea, but nevertheless it seems clear it's theoretically possible. GOOD LUCK!

[gsm_peter]

I would love to see some of these features:

 

- Drones please swim home to me or to one drone for easy pick up.

- Signal coding so they are not disturbed by other radio devices.

- Burglar control. When one get out of pattern send strong signal to others every X minute

One could use any other drone to follow lost drone.

- Very durable. Can be run over by a skier without brake

- Safety marking if sinking. When drone 4 feet under water release micro floating boie with thin fishing rope to be manually picked up.

- Drones out of pattern. Signal to boat driver that course is not in shape.

Maybe an Android app to manage/check drones

 

[9400]

GPS is way more accurate than 16'...can be accurate to less than a half an inch, horizontally and vertically, depending on how it's processed.

[thompjs]

@9400 you need survey quality GPS for that and that is $$$$ right now.

[9400]

@thompjs I know...I was just having one of my "someone's wrong on the internet" moments and had to chime in. Most of the time I have it reasonably under control, it got away from me this morning.

[jackski]

Our company does engineering & surveying. We "buy" time from a provider for our survey signal. Our accuracy is a few millimeters, 2 to 4mm I believe, depending on where we are.

[jipster43]

I had a film professor who claimed a completely computer generated film was about 10 years out. Toy Story came out a couple of months later! The moral of the story is never underestimate technological advances!

 

link

 

 

[Than_Bogan]

The big battery breakthrough has been announced every year since at least 1980. I hope this is the real one!

[Cusefan78]

GPS is very accurate these days. I have a GPS fishfinder for ice fishing that's gets me to my exact same hole from the day before within inches. I have shoveled off snow and found my hole from the previous day. You would be shocked how accurate they are. Phones are accurate because they don't need to be.

[gsm_peter]

Some more suitable features:

Adjust course. Drones please keep pattern and swim left, right, front, back or turn a bit.

Type x meters or y degres.

[SkiJay]

If waiting for "close" technology counts, another possible solution for the public lakers would be a drone copter with a holographic projector accurately placing the ultimate safe balls on the water. Give it a big tank of Nitro and it could hover and top up batteries all afternoon.

[rayn]

How about matching/synched VR googles for driver and skier. As long as you have the room, ski anywhere :)

 

[andjules]

@rayn, I've actually looked into this a bit. I think it's possible that we're only a couple of years off on that approach, certainly a few computer science nerds are looking at that tech (for non-water-skiing applications). The most likely hiccup is that we (water skiers) need very high sample/refresh/update rates (recalculating position/graphics at least 25x/sec if not much higher) - current demos I've seen aren't refreshing that fast. On the plus side, we operate mostly in 2D (our 'terrain' is flat, compared to most applications which need to work over variable terrain).

[Jordan]

I have no opinion about the likelihood of all of this, but if I could stop by my ski oartner's boathouse and just dump the buoys into the water and watch them go to the right spots

 

I WOULD GIGGLE LIKE A SCHOOL GIRL!!!

[mwetskier]

heres an alternate idea the buoys could disperse to their correct locations and then reel out a small weight that sinks to the bottom. not enough to hold the buoy in place under heavy wave action, but enough to keep it from moving around between passes. then every time a buoy senses its out of place it reels in the weight a bit until it can motor back to its original spot. so by the time the skier has dropped and rested the buoys are back where they belong.

 

maybe less battery use over all with no super accurate gps refresh rate and less constant correcting required. at the end of the set a command has them reel in their weights and head for the barn.

[Wish]

@mwetskier‌ good idea. ;-)

[Than_Bogan]

@andjules Very cool. Yeah, I think you really need 30+ frames per second for water skiing to at least match the human sampling rate. But once somebody can figure out how to do it well at a lower frame rate, it won't be long before advances in hardware, carefully optimized software*, and custom hardware can bring the speed to whatever is needed.

 

*What I do for a living, btw. It's common for me to get 4x over some "fairly good code," and when I can come up with fundamentally new approaches, sometimes 10x can happen in software alone.

[andjules]

@mwetskier there might be a couple of issues with that idea. First, "not enough to hold the buoy in place under heavy wave action"... well, a big boat goes by a bunch of boat gates each pass, within inches, which is pretty heavy wave action. Secondly, for a weight to be an effective anchor (to make it easier for the ball to keep the position), I'm pretty sure it needs to be 'heavier' than the ball's buoyancy. Which mean the (motorized) ball can't really be the delivery vehicle of the weight (at least not without adding a few more motors thrusting down, to create artificial buoyancy). And then lastly if the point of the intelligent course is to have the buoys self-organize wherever you want to ski... then you need to design based on the idea that you don't care how deep the water is. So now you'd have to make choices about how much rope each reel would carry, and additionally have sensors to manage the reel (sensing when the anchor has reached the bottom). I can't see the benefits outweighing the design costs/challenges. But... (to be cont'd)

[andjules]

In my situation (and I think this may be true for a number of us), as much as I'd love a self-organizing course, I can get by with a permanently-placed but HIDE-able course. Current/old technology gives me two choices:

- an expensive (and finicky?) sinker course

- manually attaching the balls to subfloats every time I want to take a set

 

I'm wondering a couple of ingredients from this thread's idea might help with a new sinker design, using:

- wifi/bluetooth 4/nfc (whatever wireless communication technology is best suited)

- cheap/efficient brushless computer fans as propeller engines

...so that I could drive over to my (sunken) course, send a wireless signal and then have the fans thrust the balls to the surface (you'd have the balls attached to an anchor with just enough negative buoyancy to sink them, but not requiring much effort from the propellers to raise them). The ball anchors would just slide down through the sub floats. Depending on how much/little power required by the propellors, they could just run for the 45 minutes it takes me and my ski partner to ski. Ideally I'd only have to swap out a (rechargeable) battery every few weeks?

I haven't done enough research to see if this is realistic at all, but the older sinker designs have seemed very complicated and finnicky to me; strikes me there ought to be a simpler approach to raising and sinking buoys on demand for a permanently- (or seasonally-) placed course.

[chris_logan]

@andjules to combine your theory a bit with the theory of the intelligent ski-course:

 

What if there were all maintained sub-bouys with fixed vertical rings on the top of them? You go out and deploy the smart buoys and they go the their respective (GPS) positions that aligns with your course sub-buoys. When in place, they then drop a treble hook attached to high strength fishing line to snare the verticle loops at the top of the sub-buoys. Once snared, the spool motors pull the line tight to submerge the buoys to a height within tolerance, and then a "parking brake" is set - which is essentially a spring that is equal to the force to keep the buoys submerged within tolerance (This way each buoy height is maintained at a perfect level). When you are finished, you press a button which releases the tension on all of the "smart buoys", they reel in their treble hooks, and all come back to your location (at the boat).

 

I know, that got seriously far fetched, but if we're dreaming...

[andjules]

@chris_logan‌ I've thought about this idea too - balls that swim out to the right spot and attach to permanent sub-buoys. I was contemplating magnets (some kind of ball-and-socket type design so they match easily)... or even electromagnets (or some combination) so when I'm done, I can send a wireless signal, release the connection and the motors start powering the balls back to a rendez-vous/pickup spot. Getting pretty crazy though (to be a success it's got to be an order of magnitude easier than manually clipping/unclipping balls... not sure maintaining all these electronics is likely to turn out easier).

[SkiJay]

Good point about the maintenance @andjules‌. I get to tune a lot of skis, and from what I've seen, just keeping their bindings fastened securely to their skis is apparently too much maintenance for 80% of the skiers I know.

[mwetskier]

@andjules -yeah a boat going by with in inches is pretty heavy wave action - hence the self correcting feature for the buoy to return to designated location after being displaced. thats why i suggested that every time a buoy sensed it was out of place it would take corrective action while the skier was dropping at the end of the course.

 

as for weight if an inflated buoy has 10 lbs of buoyancy then a 5 lb weight will float it at the halfway point. as long as the buoy has more buoyancy than the weight the idea is valid. we use a 3 lb fishing weight with an under inflated ball to throw out of the boat for a temporary position marker and if it floats out of position at all it does so very slowly even with the weight not touching the bottom. thats on a calm day of course.

 

but if the 3 lb lead weight is actually on the bottom it takes a pretty serious wave to move the buoy out of position. 200 lb concrete weights are used for fixed courses because we want them to remain in place for decades and they have no ability to correct their position if they get out of whack. this that were talking about here is an entirely different animal.

[Wish]

Water fill the buoys. Waves do not impact them nearly as much as air filled. Big waves will roll right over them. Plus, they move laterally far less. And it takes a fraction of the weight to hold them half way under the water. If hit, the hole system would displace easily and little shock factor with minimal damage to all things below the ball.

[Zman]

@mwetskier good idea! Another twist, the weights sink to the bottom with a tether line that can be used to sink permanent anchors. Quicker than surveying. :)