Steer by GPS

[skidawg]

Ok, new topic for all u skiers, engineers, bouy junkies, etc. Steer by gps, is it gonna happen, good bad ugly-pros cons- jump on and keep it nice!!!

[9400]

It would be nice, if it was affordable. I've been fortunate enough to ski with some really, really good skiers. When I was driving all the time and pulling 39s and 41s everyday, I had confidence in pulling anyone anywhere at anytime. In the last 4 or 5 years, I don't drive as much and I ski with one guy that runs 38 fairly often at 34 and another guy that can run 38 at 36 in spurts....because I don't drive the really short stuff all the time, I'm not nearly as consistent at putting the boat where I want to and tend to overreact to the bangs at the buoys.

That's from a driver's prospective...from a skiers prospective, I would like it even more. I get behind some not so good drivers sometimes, even in tournaments. A consistent driver is a really good feeling.

Along a similar line of questioning, someone brought up drivers being performance rated as opposed to how we rate them now...wouldn't that be a better way to evaluate drivers? I'm not a very good paperwork person, and I don't go to a lot of tournaments....but as an assistant driver, I've pulled scores exceeding the best 34 mph scores on record (in a C tournament) and the mens world record, (in practice a handful of times)....now neither of these have a videoed boat path and they had more to do with who was skiing than who was driving. The point being I know of others who are pretty good drivers that just don't bother with becoming a tournament driver because of the requirements.

[Than_Bogan]

Hopefully somebody with more in-depth knowledge of GPS data can clarify, but my understanding is that GPS positional accuracy is waay too coarse to use it directly.  We need inches (or possibly fractions of an inch for those 44' offers someday), whereas the resolution is more like 10s of feet (I think).

But velocity is far more accurate, and there are advantages in this problem like knowing you're supposed to be going in a straight line.  So maybe possible with GPS inputs alone, but doesn't feel like sufficient information to me.

As an engineer (OK, I'm a software engineer . . .), my first guess at the most plausible method of automated steering would involve a laser guidance system.  Conveniently, lasers form straight lines.  Then "all" you have to do is follow it.

But even with all the right inputs, I still think the Control System portion of this is very hard (and I'm a little closer to an expert on that -- it is software after all), because a good driver actually slightly anticipates the necessary path adjustments.  I believe it will be hard (though probably not impossible) to get a computer to do that.  Of course, the computer has the advantage that its "reflexes" are orders of magnitude better, so I suppose it's possible it wouldn't need to anticipate anything.

Very interesting topic.  Personally I feel something like this will be required if folks start running -43 some day.  (Or else go to 38 mph for the pros, but that has a lot of drawbacks.)

[clemsondave]

Not an engineer, but I think it would be easier and more accurate to drive by laser. Have a beam at each end of the lake. Not sure GPS is going to be accurate enough. I'd be surprised if it ever happens - the cost of failure is too high.

 

Side note: I can hear all the complaints coming in already! At least it would take some of the heat off ZO :-)

[Thomas Wayne]

I'm not an engineer, but I did stay at a Holiday Inn Express last night.

I think the primary problem with ANY computer-controlled steering is that a good driver actually anticipates his skier, and also uses all kinds of other subtle input to adjust for what's going on behind the boat.  It would take a very sophisticated system to emulate that, and I can't even begin to wrap my head around what the algorithm(s) would look like.

That said, I was told by a fairly reliable source that the full-screen display on some of the new boats is beta testing for the GUI that will someday accompany just such a system.  My concern, should this ever come about, is that most skiers won't actually like a dead-straight boat path - just as many don't like a truly balls-on boat speed (ZO) - but they won't know that until the AWSA makes it mandatory...

TW

[DW]

OB, the old Malibu Computron has an LED display exactly like you describe but for speed (sorry).  Three yellow LED's in center with three red LED's on each side for below/above desired or set speed.  It was pretty cool and did a good job of helping the inattentive/novice driver hone in to the desired speed.  Current GPS does not have the accuracy for the desired purpose and it also has an approximate .2 second time delay on a returned signal, so the condtioning software will have to be pretty sophisticated as mentioned.  I think most of the directional control algorithms being used today actually use an imbedded path signal for guidance.  I would think that could be a system that has potential, you would bear a significant amount of the cost within the ski course itself, but it would be amortized over all the boats that use it.  A system of that nature may not be quite as formidable a task.

[Dirt]

I think OB's laser has the most potential. My GPS with WAAS usually says it is only accurate to 7-13 feet. The laser sight aided deal does not seem like it would be very expensive or complicated.

[scoke]

 

thanks for all the ideas. we are working on it now.

 no more posting on the internet or skiing for me. I am jumping on this and hoping to make a $hitton of money on this gadget for a dying sport! might even quit my job. this will make people who dont like my favorite program, ZO, forget about their problems and give them something new to complain about even if it's only a +$10k upgrade.

cant wait to show you guys and pull OB behind it. he'll be my first test dummy skier,

[thager]

Roger ball, 3.5 Ski Nautique 196 over!

[behindpropellers]

Satloc????

 

Used in spray planes.

 

You could map the site and use the tech that surveyors use = $$

 

 http://sprayplane.net/Photo%20Gallery/albums/userpics/10003/104_0481_1.JPG

[thager]

Bolter, bolter, bolter. Missed pass I guess!

[rayn]

Not that I would know how to do this, but how bout some kind of cheap radar device that centers the boat path based on the boat guides in front of the boat and those in the back or some other kind of sensor/transmitter system(RFID) in the boat and boat guides.

 This would solve the problem not only for private lakes, but also public lakes and we would not have the same accessibility issues that we have been talking about. 

 One problem I see is retrofitting all the steering cables to accept the input of the driver assist system. It will be much easier when we get Steer by Wire :)

[skidawg]

I should add that I jacked the idea for this thread from our favorite PT Mr. Jones. I am way to lazy and dumb to come up with this for myself. Gotta give credit where it's due

[scoke]

 

thats great Mr. Jones thought of it: by the time he upgrades his boat, programmable steering will be standard!! hahaha

[TeamWally]

FS, 2 lots on Winlock Waters, 2 196's misc ski gear, wet suits, course supplies, instructional videos and the coveted "How to love falling with Zero Off" self help series, soon to be supplemented for the stainless steel tow rope and GPS steering. I quit. That is all.

[teammalibu]

You sure you want your boat path to feel like ZO

I know that bass boats used something like a laser on the trolling motors a few years back 

[Deke]

Why use a boat at all? How about an underwater monorail? BTW, I AM an engineer and DIDN'T stay in a Holiday Inn Express last night :)

[Bruce_Butterfield]

I are an engineer two.  What is a Holiday Inn Express?????

The problem with either a speed control or a steering control is not that it will keep a dead nuts speed or perfectly straight line – neither will do that - EVER.   The problem for both is that there must be a change in speed or direction for the control system to know how to respond.  How hard and how quickly the system responds is where the complaints are and the real world difficulties lie.  I can only imagine a boat getting pulled off center by a few inches and the response of the control system as it tries to compensate.  Sorry, but I’ve been in the boat with some of the world’s best drivers and developing a steering control that can sense the amount off center and compensate anywhere near as fast as a human is a huge challenge.

Steer by GPS?  No way.  Differential GPS is the only way that the speed control sort of works.  It is using position changes of feet to determine how to respond, not inches.  Lasers and radar?  Maybe.  But again, it’s the math in the computer that determines the quality of pull.   Keep thinking and no one should quite their day jobL

If there was a system that could keep a dead nuts speed (i.e. big turbo diesel with a 3ft diameter prop) and dead center (i.e. a boat running on submerged railroad tracks), I’ll bet a paycheck skiers would absolutely love it.   And this is the ONLY way that the claim of “the same pull for everyone†can be accurate.  If there is a control system that is reacting to skier input, it is by definition providing a different pull for everyone.  That is the real issue.

[h2odawg79]

Ahhh, the Human element!

Isn't it rather ironic how Hard and far we push technologies to feed our hunger for Better, and then in the end,  many of those very inovations completely replace us... -Maybe one day we'll just Pilot Drone Boats and skiers from the comfort of our own couch! 

[jdarwin]

If the "ideal" is a static pull, then eliminate the boat, install a rail system (hydraulic I would guess) along the bottom of the lake straight down the course with a bar sticking out of the water to attach the rope.  Program your speed for 34.2 and away you go.  If I understand Bruce's comments, absolutes don't apply here.  The driver/speed control is reacting to input - not maintaining a set speed.  The speed is an "average" over the length of the course.  The boat path is no different.

[MrJones]

No credit to me Dawg. A bald guy in his 50's who beat me by 5 buoys (Mr. Raley) brought it up when we were chatting at Nationals. I have not idea how it would be implemented, but I would welcome it. As someone who has limited access to drivers/coaches, being able to put any warm body behind the wheel to get the boat on line and up to speed is very appealing. My wife is one of my absolute favorite drivers and coaches. Problem is that unless you are someone like the aforementioned Mr. Raley it is very hard to do both well at the same time. A "built in" driver would be awesome in my situation.

[skidawg]

I say nay as long as JD is five min away, thanks for the pull!

[thager]

I just wish I could find someone here interested in skiing. Daughter and wife are good drivers but sure would be nice to have another skier around.

[Donski]

I am not an engineer, can’t even spell it, but I do own several laser that we use for construction application. It would be great to have indicators with lights or arrows on the dash that could assist the driver with staying centered. Lasers would be one solution but I don’t believe they would be a practical one.  Seems to me that a wire pulled down the center line, under water could be made to work. A sensor bar mounted in the boat (below the pylon) should be able pick up the wire and relay the boats relation to the wire.

If I can put a sensor bar on my TV so I can Wii bowl, how hard can it be to put a senor in a boat?J

[Thomas Wayne]

"If the "ideal" is a static pull, then eliminate the boat, install arail system (hydraulic I would guess) along the bottom of the lakestraight down the course with a bar sticking out of the water to attachthe rope. "

Something very much like this was conceptualized - complete with images - at least a decade ago in Waterski magazine when there was a big push to introduce Waterskiing into the Olympics.  The ideas was to eliminate the human variable at the non-business end of the rope.  I remember a tiny hull-like pod riding on the surface with a robot-looking "driver", and submerged rails underneath.

TW

[Andre]

How about an overhead monorail?Lot less energy needed to move the dolley over the water then under...No more wakes!!!

Or a tracer wire in the course mainline that a captor on the boat would follow?

[animal]

Can you say cable ski park?

[Than_Bogan]

scoke, any chance I can invest my life savings in your little endeavor?  /vanillaforum/js/tinymce/jscripts/tiny_mce/plugins/emotions/images/smiley-laughing.gif  (Yeah, this has no chance of being a good business to go into.)

But the academic exercise is amusing (to a geek like me), and since a few people have brought up the software side of this, I'll use it as excuse to ramble a bit.

Firstly, it's certainly true that a perfect boat path cannot ever be achieved by a steered boat, regardless of how it is steered.  The "rail" systems that a few folks describe possibly could do that, but of course that's a pretty different character to the sport, with an even more ridiculous barrier to entry than we already have.

As far as whether a computer could do what a human driver does, my answer is a qualified yes.  This is a HARD problem, and no doubt the first attempt at it would be pretty dismal.  However, the information is present, and while computers are morons, they are extremely fast morons, which in this particular type of problem can overcome a lot.

At a very high level, the outline of the approach I'd suggest would be to maintain two mostly seperate "channels" into the control systems -- I'll dub these reactive and proactive.

The first is the directly measured "where am I now" information, which needs to include (at least) the current deviation of the center of the boat, the current angle of the boat [these for example can be measured using a front and rear laser sensor], and the current position of the rudder [which can be measured from the boat itself].  This is the reactive portion of the control system: Figure out how to get back where you want to be as if the skier simply stopped skiing.  This is a non-trivial problem, but there is a lot of theory out there on building (reactive) control systems, so I have confidence it is doable.

The second part is needed to emulate the predictive capability of a human driver.  A human driver has knowledge not just of where he is now, but what is likely to happen in the future.  This is because he has a "model" in his mind of what the skier is trying to do, which is (obviously) an attempt to navigate a very restricted path, not just to pull the boat all over the place randomly.  So we can get a first approximation of where in this sequence the skier "should" be from our current position in the course and the rope length.  Then add in the recent history of pull on the boat (from our partner in crime Zero Off) to refine this estimate, and we can make a rather educated guess about what forces are going to be hitting us in the near future.

Finally, we have to combine what our reactive and proactive components are telling us to do.  Even this step is not trivial, but it might be the case that a weighted sum is good enough.  The value of these weights are left as an exercise...

No easy problem, that's for sure -- but I do think the software side would be possible if there were a market to justify the effort!!

[bmiller3536]

The last thing I want is my driver to be staring down at the dash board looking at red and yellow lights.

[Jody_Seal]

Yea! Lets add another $3-5k to the price of doing a already over gadgeted, over ruled, over blown and over priced sport just for a couple of discontented skiers . Wait! Are we not going down this road already?? Zero OFF!!!

[dthate]

I sure do like boats, the way they look , drive, feel, smell, may not be perfect but I love them. We should all strive to be the best drivers we can and encourage others to be, and train them even if it means getting a sloppy ride now and then. Not interested in removing boats and people from the sport, for a cable park. 

[Than_Bogan]

Couldn't agree more, dthate.  The whole character of the activity would change without a boat.  I think getting rid of boats would be extremely bad for the sport overall.

[h2odawg79]

As far as the Olympics is concerned, I never understood why it was not simply turned into a "Team" sport like the 2 man Bob sled or Luge...  (Driver/Skier)

Cable Ski parks and 3 event tourney's used to be HUGE in Europe... I believe they still have sanctioned events. Cable parks actually started in the 60's as Water Ski parks and were eventually replaced by the Demand for Boarding. Especially in countries where private ski lakes are all but impossible and where the overall cost is impractical and out of reach for the Masses. I believe there are some 50 Cable parks in Germany alone.

Cable is Not the same as a Boat pull. But, it is still Fun and could be a very Cool draw for competitors and audiences. It would most definitely be it's own Sport, but as the cost of Boating keeps going Up, Up, Up it's (Cable parks) appeal will become a more and more viable option... -Just look at how the Boarders have adopted the Parks and then redefined their whole sport through the versatility of these Parks...     

[dthate]

I think it's great for boarder's, it would be cool if they could zip-tie a boom box to the cable. Did that come off old and elitist?

[Than_Bogan]

Excellent points on cable, 79.

[Ed_Obermeier]

Very interesting to see this topic pop up at this time.  It happens that I spoke just yesterday with a potential customer, located it so happens outside the US, who is looking to have a customized course built to use with a system he says he's already well along with to automate the boats steering, goal being a perfect line through the course with skier in tow.  He didn't go into a lot of detail on his system (and I didn't quiz him too much on it) so I'm uncertain to how he's going about it (gps, laser, ??) but speaking to him I was convinced that in his mind at least he's fairly well along with developement.  So yes, it would appear (to me at least) that there is someone actually and actively developing such a system at this time with an eye towards bringing it to market in the forseeable future.  I know this sounds like a load of crap (that I had this conversation I mean) but I swear it's the truth.  For whatever it worth and whatever it brings to this discussion. 

Ed 

[Deke]

Ed, I vaguely remember seeing a short paragraph in Waterski Mag or The Waterskier some months ago about a person in Germany working on this sort of thing. If I recall it was the no boat approach though.

[Bud Man]

An engineer at a speed control company told me that they had a GPS steering system that did work but the problem was in the course, not the boat. He said that the wind shifts all 26 buoys on an individual anchored course over enough to make the boat run over them and the skier closer to the turns on one side and farther on the other. Not to mention how far off a cable course can be. A human driver centers the boat in the lane regardless of the wind shift.

Even if he was pulling my leg, I would not know. But I had no reason to doubt him.

[Steven]

Very good point Bud!

[Jim]

From an engineering standpoint it is hard for me to imagine any obstacle that could not be overcome. On the other hand from a business standpoint I can't see how you overcome the financial side of it. Speed control is useable by everyone who owns an inboard ski/wakeboard boat. Small enough market but their making it work. How would you ever get a GPS steer system to be profitable in a minuscule number of boats? What if it's not retrofittable? Sport would implode.

[h2odawg79]

Re: "The real killer would be if the U.S. Waterski Federation made such a system mandatory in a arbitrary way like they did with Zero off".

Ageed!  -Unfortunetely, $$$ is always the driving force behind evolution. You can bet that enuf people (inside people) were very certain that they could bolster new Boat sales by implementing ZO and making 1000's and 1000's of boats obsolete. Too Bad they did'nt also factor in the worst economy in 70 yrs. with the timing of it.

Don't be fooled, implementing ZO had much more to do with perspective profits, $$$ (sales, kickbacks and incentives) then it ever had to do with actually improving our Little obscure sport.    

[Steven]

I'm already out of the game when it comes to ZO. I'm not buying a boat that can be equipped with it and I'm certainly not going to purchase a gps steering system. If they want to continue to pursue skiing at the Olympics, I think it's a great idea! But I don't see how it could help the sport of skiing if it is ever mandated in tourneys (which I highly doubt) At least I hope they're smarter than that!

[Roger]

I don't know why they think that will make a difference. There are no motorized sports in the Olympics regardess of speed control or steering systems...

[MattP]

It would be cool for skiing to be in the Olympics. We all want skiing on a world stage like that but we all know deep down that it will never happen.

[Jim]

Don't they use motorcycles in some of the olympic velodrome bicycle events?

 

Not that it matters, Greece was the last shot for waterskiing. Greece wanted waterskiing and nominated it but because they were so late and disorganized in their preparations the olympic committee removed their option for adding a sport. Now it is all about REMOVING sports from the olympics to get some cost containment. No more money from the USOC for the Pan Am Games so how long does organized water ski pursue the "dream"? What benefit comes back from USA-WS's continued participation as a USOC member, what costs? No idea, but would like to know. Maybe the biggest problem is that as the "dream" has faded it hasn't been replaced with a new path towards growing the sport at the top end.

[ForrestGump]

USA Waterski is a dart without feathers.

[Roger]

The motorcycles used in the velodrome bicycle events are used only to get the bicycles up to speed, not during the scoring of the event. Back in the 70s when I was an active skydiver, skydiving was in the olympics for a short time, again the motor (airplane) was only used to set up the event, not used during the part that is the competition. Unless they change how they feel about motors being used directly in the scored event, I just don't see it happening.

[Steven]

Not that it's going to happen but couldn't they attach a hull to a railway (of sorts) that is on the bottom of the lake that is used to propel and guide the hull down the lake. They could have complete control of the speed  and path. just a thought. But again, never gonna happen!