colo_skier

@ShaneH, I agree that the goal of Z0 is a constant speed through the course that will result in an exact time. I think that is the goal of PP also. I was more wondering on how each of the engineering teams tackled the problem. They both have access to the same input information and have the same control ability. However as has been documented the resultant skiing experience prior to Z-box for PPSG was different. Could it just be the addition of acceleromoter information allows a much more accurate engine reaction and control ability? I seem to remember from long ago college days that acceleration is a second differential of distance or something like that. Maybe more integration's of different information curves allows a more accurate control of time through the course? Bottom line for me is, to the people that can tell the difference (not me I don't ski that good) do the 2 systems seem to ski the same now? ie Is it all in the math?

I don't have zero off but have driven a boat with it and noticed and heard from skiers that have skied it and the comment is that it is always exactly on time. It would thus seem that zero-off is primarily targeting a time through the course rather than a constant speed to achieve that time. Some people have commented that zero-off does not have an "in tolerance" ability, ie It always hits the exact time rather than a time that is still good. Of course the 1st goal of timing without any other variable (the skier load) dictates the second (constant speed). Perfect Pass on the other hand seems to be targeting a specific RPM that will achieve the perfect time. From all that has been written about the difference between the 2 the targeted time method seems to give more repeatable times. I don't think this is any way related to the control mechanism of the speed control as we have PP DBW and servo controlled systems at the lake I ski at and they both perform the same. I wonder if this is due to the fact that if the main goal (algorithm) is to hit a specific time rather than a calculated rpm to achieve that time, then the speed control is operating in just one calculation domain (time). It is the base that all of the digital is working in after all. Just an engineering guess from all that I have read about the ZO PP debate.

@phil2360 Agreed "trick" was probably the wrong term to use. Augment would have been a better term. There must be some computing going on to warrant the micro in the z-box. As that is were the accelerometer is at I was assuming some sort of extra information content being added into the data stream that Stargazer uses. I heard somewhere that the ZO uses 2 ARM 7's which is quite a lot of micopower to analyze NMEA data. Therefore they must be doing a lot more vector and speed math form other data streams. Bottom line is if the system works it's a good thing for us older boat owners.

If i were to hazard a guess I would say that the zbox is "massaging" the raw GPS data being fed to the Stargazer based on Accelerator feedback information and settings in some look up tables based on the a b c settings entered on the multi line guage. Since Stargazer can be used without the zbox the zbox must somehow "trick" Stargazer into calculating position, speed and acceleration form differing the raw data fed to the Stargazer unit.

This is the product link http://www.analog.com/en/mems-sensors/mems-accelerometers/adxl103/products/product.html here's the micro in there http://www.keil.com/dd/docs/datashts/philips/lpc2114_2124.pdf

Forgot about the hair issue. Maybe have someone else wear it.

Why not try wearing a go pro on your head and have it record what the mirror sees. Or mount it on a tripod behind the driver and point it at the mirror.

Thanks John and Brent. The one I was looking for and found was at Warman lake. This other one is good to. This makes my look a little less crazy when I ski once the ice is gone.

Anybody know were the video is of the guys sking were they back the boat up to the ice and the skier holds up a sheet of ice? I can#t find it with any search. This one can be closed I found it in the winter sking in washington. For some reason the link was not highlighting so I missed it yesterday.

Thanks got it, looks like this is were ral ski's. I was looking in the wrong country, Argentina!!!

Were is it?

I am there for 7 days so I should be able to put business Scott's way as well. I last skied on Nov31st in 42 degree water so will really need to get a good ski fix to last me till the middle of April when we start back up here.

pq2 Thanks for getting back so quickly. My ski buddy has some friends that have skied with Scott and some are actually featured on the Cancun ski Web site. We are actually staying at the Moon Palace and have access to shuttles to the Sun Palace. Based on this I was going to bring my ski stuff down and see about getting some early season sets in.

I am going to Cancun the last week of March and had hoped to ski since the entrance to ski Cancun is directly across from the Sun Palace resort. My ski partner goes there once a year and skis the Club Med course. She doesn't like to be the first skier in the morning as their job is to scare away the crocodiles with the boat. @pq2 I guess this is me letting you know I am heading down there.

I see what looks like a ski lake at 27°51'50.95"N 97°36'2.12"W on Goggle earth near a town called Calallen TX. Looks to be 12 miles north west of CC. Looking at the ccwaterski web site picture of glass cutters and a few of there videos it looks like they are located at 27°51'27.32"N 97°34'53.07"W. about a mile away as the crow flies from that ski lake.

2nd video shows some great info. Her pull out looks picture perfect with the hip drop and level shoulders. This is the first angle I have seen were that really is clearly shown. Also in the slow-mo section after ball 3 coming out of the wake the direction change in the ski and then after 4 the amount of down course distance as the ski and the boat hook up, and Katrina gets pulled down course. No panic just staying with it. Wish I could even wish for composure on a ski like that.

2nd video shows some great info. Her pull out looks picture perfect with the hip drop and level shoulders. This is the first angle I have seen were that really is clearly shown. Also in the slow-mo section after ball 3 coming out of the wake the direction change in the ski and then after 4 the amount of down course distance as the ski and the boat hook up, and Katrina gets pulled down course. No panic just staying with it. Wish I could even wish for composure on a ski like that.

Got it added to my Google push pins. No that far from the Quarry.

Got it added to my Google push pins. No that far from the Quarry.

Thanks Horton, Still makes it look easy even a few years ago!!!

BTW were is Canyon lake in So Cal.

OK it found it with Nate Smith. This seems to work better for me so I like it!!! Thanks for upgrading this.

Sorry it is the Krista video of her doing passes from the end of the course and the other was Nate Smith from the Syndicate team. I was really more interested in if the search engine could find them. With "Krista" in the search it found the "You think 35 is hard? Krista is a silly blonde girl and she can run it. Why can't you?" thread. However the Nate smith is still eluding me.

Regardless of the squirrel comment A would be my choice.

Horton, I am always trying to get back to the video of Matt skiing from the end of the course were the heading was something like Boat driving. It is really good to show people that don't ski and want some idea of how fast a skier goes across course. I have yet to find it via a search engine. Any comments? Also the one of Katrina making the 39 off with something like 39 off is easy...