GGS LX launch monitor

[bubba22]

Yes I agree. I am interested in the spin axis numbers. Measuring total spin is great but getting the actual spin tilt is what is important because that will determine the sidespin and actual curve of the ball. Interested in how accurate the spin tilt is. I agree 100% that how the GSA software handles the spin is key.

[northgolf]

Are the LX launch monitors going to be upgradeable; that is, could you upgrade from LX2 to LX3 with the purchase of an additional camera? The line "Use your existing cameras" seems to hint at that as a possibility.

This is a promising alternative the the GC2 and I might snap it up if it ever becomes available.

[bubs3141]

I think everyone is keeping an eye on this. I am not holding my breath that it will ever be completed. Especially at that price point since the GC2 is at least twice as expensive. Even more when you add in their courses.

[ZMax]

Yes, it can upgraded by adding cameras.

[mmlincon]

from what I understand these are in production or at least being sent in for production. Martin has had the prototype working for well over a year ( or so he has said ). The LX is upgradeable for sure. Theoretically you could use the LX during the golfing season and then move cameras back to your permanent simulator setup during the winter months. Might not be all the necessary if the LX is that accurate, but you might want to do that to deal with the L and R handed people issues. It's one of the big benefits of the GGS systems - flexibility and options.

[northgolf]

mmlincon,

Thanks for the details. I am hoping the LX is that accurate - the measure will be against the GC2. I want a reasonable sized self contained camera based system that does launch angle, path, velocity, spin, and spin axis. The upgrade ability to do club data is a nice extra, but not my immediate need. I do want accuracy.

[ZMax]

Just noticed the price increases. Considering that the LX will only have two captures of the ball to make measurements(Vector Pro), good luck with the price increase...

GSA LX series launch monitors will be available in May 2012.
Prices:



LX1 $2,499 with 21 ProX golf courses

LX2 $ 3,999 with 21 ProX golf courses

[northgolf]

1.5K$ bump, ouch.

ZMax - do you know how many captures the GC2 takes?

[ZMax]

Only Foresight engineering/support knows for sure but the users can not verify the amount of captures or even take a look at one. From what I've read, it appears to take the initial ball at rest, then maybe 1, 2, or 3 after impact. No way for us to know.

[mmlincon]

It is certainly less tempting to just pick one up now......

[northgolf]

I just went to the web site.

Not only has the price changed, but you look at the solutions and they are different as well.

The LX1 does the complete ball tracking with one camera - if I remember correctly, it does all the old LX2 was previously advertised to do. The LX2 now looks to be a separate add on which holds a camera directly above the ball for tracking the club path. So, it looks like the functionality at the price points are the same ($2.5K for ball information, another $2K for the new LX2 add on).

If the LX1 does what it is supposed to do, then it is very attractive to me as I am interested in ball flight not so much club information.

The gist of my message is: look at the site - the final product looks different from what we were seeing two weeks ago.

[ZMax]

Once again, another change in direction. LX1 will now do all ball measurements with one camera, according to his site. With this method, I can see accuracy dropping. Think about it. And Think about what happens when you hit it fat. Then again, I could be wrong. It might all work well. I'm not going to spend $2500 to find out.

The LX2 add-on should work better for club data than the HMT if you can swing with that thing hanging over the hitting area.

[northgolf]

If I was interested in the club data, then the LX2 add-on would be a real issue - I don't want anything in my view over the ball and I expect I would find the LX2 very annoying.

For me, the issue of 1 camera vs. 2 cameras is getting the second photo taken in time. Accuracy is just a matter of knowing the exact amount of time that passed between the two images - I am not sure why 2 cameras would be better than one in that department. The advantage of one camera is you have only 1 frame of reference from which the images are taken - that should make the calculations easier since you don't have to account for the difference between two frames of reference.

I am fairly confident that launch angle, spin rate, spin access, and speed can calculated with a reasonable degree of accuracy. My concern is path - that one seems a bit more of a challenge depending on the resolution of the camera.

As to hitting it fat, how would that affect the measurement of the ball? Are you worried about the mat moving and causing the LX1 to move? I'm not understanding that issue.

[ZMax]

Northgolf,

The cameras that are being used here are not fast enough to capture multiple shots of the ball after impact. From what I can tell, he's taking the initial shot of the ball when it's placed on the tee for reference, then one capture after impact. That capture after impact has to be taken as soon as possible. We're talking 15-50us after impact. Which means the ball might have only traveled 1/2" to an inch.

Is 1/2" to an inch enough distance to provide accurate ball measurements?

Hitting it fat could trigger the camera too early which will affect the measurements. Might be avoided if using a trigger mat. Even the GC2(which is suppose to take multiple captures of the ball) doesn't like it when you hit slightly behind the ball.

I'm not a genius like Martin but I do have some experience with these cameras. It's also possible that Martin is doing something else with the measurements that he has yet to write about on his site.

[bubba22]

I tend to agree with ZMax. We have discussed this before. Not sure how Martin will get the captures with only 1 camera. I suspect there will be an initial pic and then after the ball strike there will be pulsing strobe to get a strobe effect to allow for multiple pics? Only 1 cam will not allow for a stereotactic view. I am not convinced of the accuracy with 1 cam.

[Andisblue]

I'm not convinced that the gc2 uses stereo cams either.

Notice how you can cover up one cam and the gc2 still sees the ball, but not the other? I bet one cam is just for the initial location.

[bubba22]

No I disagree. I think the GC2 uses 2 cams. One cam does locate the ball and image processing tells the system a ball is found and ready to be launched. Once launched that cam determines ballspeed and direction. The 2nd cam will measure spin.

[northgolf]

Oh my, we are out here with the lions and tigers and bears.

I think I'll be the guinea pig for Martin and this group. Hell, it can't be any worse than the p3pro.

[ZMax]

Oh my, we are out here with the lions and tigers and bears.

I think I'll be the guinea pig for Martin and this group. Hell, it can't be any worse than the p3pro.

Well, just about anything is better than the P3pro. LOL!!

I was hoping for the LX1 to use at least two cameras for ball measurements. From his comments on the LX page, he is aiming to compete with the GC2. If it works and measurements are as good as the PX5, it'll be a killer product.

[bubba22]

Well I agree ZMax. I just think that 1 cam may not be enough. The way it may work would be to have the cam take an initial pic and then strobe the shot with the shutter wide open to get multiple shots of the ball ie the strobe effect (stroboscopic photography). That would be good to measure spin and spin tilt. I suspect that the GC2 does that with one of the cams. I just think with 1 cam it will only be 2d and there probably will be some error due to parallax http://www.golfachiever.com/web/Tech...amerapaper.pdf . 2 cams at 90 degrees to each other or angled somehow is the best option. But lets see what comes about the LX1. I know Protee are using 3 cams (much like the About golf systems) to look at spin etc.

[mmlincon]

"The trigger signal goes through a precise digital delay circuit so that the exact time interval between the two images is known.
Knowing the time between the two captured images allows us to calculate the ball speed, spin rate and axis tilt.
Launch angle is simply calculated from measuring the height variation between the two images."


http://www.golfsimfactory.com/LXSetup.html


This makes it sound as if there are actually two images of the ball being taken in motion. What is not clear is how this functions differently between the audio trigger and IR trigger. With audio you would get impact and shortly afterwards. With the IR you would have slightly before and after impact( I'm assuming the same type of trigger used with the CX5).



Really one camera could handle the multiple exposures, just not sure the model I have can. If you can grab multiple shots on one camera, why not do three? It should lead to more accurate measurements and calculations. I really don't think we have all the info on this new product yet though.



I have other concerns. Like without a fixed location for the ball how is the focusing going to work unless it has auto focus? You can work around that with aperture, but that reduces exposure which maybe what the strobe is for. You would also need some kind of search routine to 1. find the ball and 2. determine the original size. Without extremely accurate focus all the measurements are going to be iffy. In the current software there is no options for dynamically determining the ball size in the image. This must be set and measured manually. Perhaps the LX has auto focus lenses and some camera buffers to allow for multiple images, it would help justify the price increases.


This "new" design is a little surprising, if the images are accurate at all, as it looks limited to the one camera. I'm not sure that the "use your existing camera!" is all that great of a selling point if it can only hold and use one. How much is just the base then? That might be worth an inquiry....

[ZMax]

mmlincoln,

I don't believe the Chameleon is fast enough to take multiple captues of the ball before the first revolution is complete. Perhaps he is using multiple strobes with one exposure.

And as for indoor, is he using the trigger mat to trigger the camera?

The focus question is a good one. The ball would need to be at an exact location from the LX every time.

[mmlincon]

"System includes double FiberBuilt grass panel hitting mat for use as a full feature golf simulator"

comes with the grass panels so I'm assuming it has the triggers for indoor use.

hmmm, strobe photography is a possibility. it could help deal with the focus issue as well.

[bubba22]

Exactly what I was saying. He may be attempting a single exposure and using the strobe to get multiple exposures. I suspect the GC2 is doing that with it's cams. I think the focus question as well as ball recognition is a good question.

[northgolf]

bubba,

According to Martin's LX page, he will be determining path (azimuth) by calculating the difference in image size of the golf ball. The amount of error in ball path will come down to the resolution of the camera (that is, one pixel equals maps to what measure of distance at the ball). If he can accurately determine the distance of the ball from the camera, then the parallax issues go away.

[mmlincon]

bubba,

According to Martin's LX page, he will be determining path (azimuth) by calculating the difference in image size of the golf ball. The amount of error in ball path will come down to the resolution of the camera (that is, one pixel equals maps to what measure of distance at the ball). If he can accurately determine the distance of the ball from the camera, then the parallax issues go away.

Exactly, which is what makes focus so critical. Thinking through the strobe method this seems feasible.

[bubba22]

There will always be a question of parallax. Horizontal azimuth is always a question based on 1 and even 2 side cameras as determining this from ball size is subject to more error than an overhead cam. As you say, focus and pixel quality is extremely important. The Vector does the same thing as the GC2 in determining horizontal direction by ball size and I think that is probably the weakest measurement in those units.

[ZMax]

For what it's worth. The LX function is now selectable in GSAcontrol. Not sure exactly when it was added. An update from Red Chain is still needed I believe for GSA to accept spin data. May should be interesting. Northgolf has already volunteered to be a guinea pig.

[mmlincon]

Yeah, I've been waiting for that GSA update to play with the spin camera more. I was wondering if the spin camera data is working in ProX - that might be worth playing with.....

[bubba22]

Good question mmlincon. Let us know about Prox. Remind me again how the GC2 inputs the spin data in their Red Chain courses?? As well other sims like Golfotron http://www.golfotron.com/en-GB.html must have a spin input setup with their Red Chain versions?