VisTrak LA settings

[COgolfengineer]

The CP comes pre-loaded with launch angle settings for each club, which I found to be the same as Trackman's advertised launch angles for PGA tour players. I'd like to get his dialed in a bit more so just curious what other people are using. I have a VcamC that measures launch angle but if the shot is misread (happens often), then the launch angle goes back to the default numbers for that club and really messes with the carry distance in the game sim. So if I can make the default launch angle roughly the average of my shots, then if the Vcam misreads, it won't be a huge deal.

I took a bunch of 7-iron shots and the VcamC measured anywhere between 20-25deg and based on where the ball was hitting the screen, the measurement seems pretty accurate using basic trigonometry. If the VcamC misreads, the 7-iron launch angle is set to 16.3deg, so seems I should set it to 22.5deg.

I could do this for every club but would be quite time consuming, and the launch angle would be based on just my swing, so it would be great to get other peoples input.

Thanks.

[Lewis837]

I don't have measured values for my launch angles yet but your post got me thinking. So I did some measurements on the VCam LA measurements and for my set up it was pretty accurate. I placed a small white square at a known height and distance from the launch point and triggered the camera. Comparing the calculated value to the measured value for the launch angle it was quite accurate (fractions of a degree error). My launch angle for a 7 iron was similar to yours in the low 20 - 22 degrees.

Then I did some web searching based on your comments to see if I could find better values for the defaults as PGA tour values might be a bit off for my 14 handicap swing Lots of thoughts out on the web and it seems the launch angle is related to swing speed and angle of attack. I found this and I am thinking of using it as the defaults. OK I confess it is the LPGA values but for my swing it would be a better starting point then a tour swing which I definitely don't have. The 19 degree value is closer to what we are seeing so it would seem to be a better starting point then the tour 16.3.

[Lewis837]

Looks like the table link did not cut and paste well so these are the values I was referencing:

Club speed Attack angle Ball Speed Launch Angle
Driver 94 3.00 140 13.2
3-wood 90 -0.90 132 11.2
5-wood 88 -1.80 128 12.1
7-wood 85 -3.00 123 12.7
4 -iron 80 -1.70 116 14.3
5 -iron 79 -1.90 112 14.8
6 -iron 78 -2.30 109 17.1
7 -iron 76 -2.30 104 19
8 -iron 74 -3.10 100 20.8
9 -iron 72 -3.10 93 23.9
PW 70 -2.80 86 25.7

And a link tot he article:

https://golf.com/instruction/driving/this-is-how-far-pga-and-lpga-tour-players-hit-it-with-every-club/

Definitely could use measured values for my actual swings but I am wondering if it is better to use angles that are more ideal around a realistic swing speed. If my friends are coming over should the simulator be customized to all my swing values or modeled after something else.

The good news for me anyway is that my VCam rarely misses the correct measured value which is different then COgolfengineer problem In his case the ceiling mount causes missing values and so the default launch angle becomes more important.

[keither5150]

To help dial in the Vcam..... measure the distance from tee to screen. Hit a shot.... measure the height of the ball mark on the screen. If your math is not great, you can use this right angle triangle calculator. Right Triangle Angle And Side Calculator (csgnetwork.com)

The Vcam should be accurate within 1/2 of a degree for LA. If you are using the single camera Vistrak only, this will help you to set your defaults.

[COgolfengineer]

Thanks Lewis837.

Yep I have a copy of the PGA and LPGA tables. Unfortunately, I'm not a PGA player and probably play more like a LPGA player, oh well. I totally agree with you; what default launch angle is best to use? What you typically hit (which may or may not be similar to friends who play), or a default launch angle of what you should be hitting? I found another article that gave an equation for launch angle vs club loft and the overall shape of the curve seems reasonable. Here's the link.

https://www.tutelman.com/golf/design/swing2.php

This is exactly the reason why having a launch monitor that can measure launch angle is so important! This is why it's frustrating when I bought the VisTrak IRVC unit that is suppose to measure launch angle with the ceiling mounted Vcam, and low and behold, isn't reliable. I have some emails with Martin asking him about converting the VcamC to the floor Vcam vs adding another VcamC and making it a Stereo unit, so we'll see. Lewis837 you seem pretty happy with your floor Vcam? What's your other cameras? And you went with the Chicago Canvas black fabric for the side curtains?

Thanks keither5150, that's exactly what I did to measure my launch angle and compared it to the VcamC measurement (when it would work). The few shots I did lined up pretty close.

I'm still confused on why the VcamC isn't reliable? When it does measure the launch angle, it seems accurate and I see the 2 frames it used to calculate and based on the distance and height, it calculates an angle, pretty simple math. There were 2 repeat conditions that would cause the VcamC to not measure the launch angle.

1. The times where the VcamC didn't work, the frame images were really dark and you could barely see the ball, so it didn't capture any image of the ball. When it does work, all the images of the ball were bright. If I would place a ball down and the image on the VcamC was dark, I would re-trigger and then the image was bright, so seems like something in the software that randomly (random to me but probably not actually random in the software) causes the VcamC images to go really dark.
2. Other times it wouldn't work were with chip shots where the wedge was travelling below the ball and the VcamC recorded a very large ball size because the club threw off the measurement. With the wrongly large ball size at the 2nd frame, it was so far off the height calibration table that it couldn't find a height so it couldn't calculate a launch angle.

Both of these issues seem fixable. I'm sure there's other details on why the IRVC was canned and with all the other variants, I appreciate Martin's New Year's resolution to focus on fewer products. It's just frustrating to have to migrate to a different configuration when it seems like all the guts are there with what I have.

[keither5150]

Best thing to do..... When you have a misread from those two conditions..... Send a email along with the vid file of the shot to Martin. The vid file is located in your C://GSAgolf folder. Just check what shot # it is and send the vid file via email to Martin.

[Lewis837]

you wrote:
you seem pretty happy with your floor Vcam? What's your other cameras? And you went with the Chicago Canvas black fabric for the side curtains?

I actually have 4 lower frame rate cameras and a line scan camera from my old CX3 system. H and V cameras, line scan camera and 2 more from the old club tracking system. I recently purchased the higher frame rate VisiTrak Eagle so now I am testing the VisiTrak Eagle with a side mounted VCam which is just the old vertical cam from the CX3. I have enough to set up the stereo system which would be 2X of the low speed cameras mounted on the ceiling but I am spaced challenged and I am nervous that I wouldn't have enough distance between the 2 ceiling cameras as I am offset from the center line of the enclosure.

I know it is frustrating to have your IRVC unit fall by the wayside but I really appreciate that Martin lets you migrate older purchases and reuse components as he improves things. At least for me, and I hope for you, your investment is not wasted but the starting point for an enhanced system.

Currently as you noted, the swing speeds impact the delay times and I am happy with the Vcam set up for the full to mid swing speed shots but chipping is still something that I am working to resolve. Again it could be my space limitations but I haven't found the right combination of settings to have full shots register as well as lower speed chips. The delay by club helps but unless you have a long measurement runway and the lens (3.5-4mm) it is a challenge to get the ball in the measurement window for all swing speeds. I'm interested in seeing the impact of the GPIO approach that Martin is working on.

Chicago Canvas cloth works well as a back drop and they shipped quickly.

[COgolfengineer]

keither5150 I would send some of these VcamC issues to Martin along with the videos, but I don't want to give him some problems with a system that he's dumped. I would like to move forward with either the floor Vcam conversion or buying another VcamC to get a VisTrak Stereo system, which I prefer to go the Stereo route to keep all the cameras on the ceiling with the bonus of not needing non-reflective fabric because I would certainly have to change out my side curtains if I went the floor Vcam route.

I'm an electrical engineer so my questions are more for my curiosity and understanding the root cause of the issues. The more I understand under the hood of the system, the more I can problem-solve on my own.

On different topic, as a fun project, I would like to make the backside of the IR unit cleaner by making a circuit board that takes in a single 120Vac power and generates the voltages needed for the IR panels and the ethernet to USB converter. Currently, the power to each of the 4 IR panels has its own 120Vac wall wort which just adds to the bulk. And then I'd like to make a case for the backside so that none of the electronics are exposed.

Lewis837 Oh wow you have quite a few cameras! I agree with you that it's nice to re-use the hardware you have but configure it to a different system. It's smart that Martin basically uses 2 different cameras for all the different setups. So if I can just add another base camera and convert my IRVC to a Stereo setup and it works well, then that's great! And then add another camera later to get measured spin and I'm all set!

Yeah the Vcam trigger delay issues is exactly the inherent problem to that method. But if it can be tuned to fit all scenarios, then it's all good. The hardware trigger approach should be way better than the software trigger approach. I'm not a software guy, but I imagine a software trigger can be dependent on the CPU and the overall load on the CPU, which will be extremely variable person to person. So a hardware approach should get around all of that.

Is the Vcam triggered some time delay after the VisTrak camera detects the ball strike? If it is, maybe it should be set to a time delay after the ball leaves the VisTrak camera FOV or based on the last frame it captured the ball? This puts in an element of time and distance for the Vcam trigger (has to be hardware trigger, although the ball being in the FOV is base don the software, so maybe this doesn't work but the main idea is to add some distance into the Vcam trigger). That should at least guarantee that the ball is ahead of the club. If this could be done, then you would need a 0ms trigger delay on woods and slowly go up to irons and then to wedges, but you could even possibly have the trigger delay set to 0 for all clubs.

[keither5150]

Adding that GPIO cable will not make a difference. I have tried it with and without. A sure fire way for the vcam to trigger at the correct time is to have a line scan camera.... Martin supplies them but they are expensive.... There is a short period of time that occurs when the ball is struck to the time that the camera is triggered. With the driver, the ball will travel about 12 inches from the tee. before the images are captured. The new stereo system verses the old setup ......captures the images within the first 18 inches of ball flight. The old stereo system relies on a trigger camera or linescan camera. The farther away that you measure the ball, the more precise the triggering needs to be. Using the Vistrak Vcam system without a LS cam, will occasionally have a shot that is not in the FOV of the Vcam.... In this instance, the default LA for the club selected would be used......not really ideal. The cost of the LS cam is getting close to another Vcam. So if you want accurate LA all the time....go stereo. I will be detailing the differences between the new stereo system and the older stereo system over the next week or so.

[Lewis837]

I like the sound of this but as usual I'm a little confused. I thought the stereo setup had stereo cameras 24-48" from the VisiTrak Eagle camera which was 24" inches from the tee. The stereo cameras were pointed down to the center line. But now it sounds like they might need to be inline with the eagle pointed at the tee or slightly in front. I know Martin was updating the installation instructions but I can't find anything new like on the website. Is there a link to the new setup steps - as I said I like where this headed and would like to do some testing.

[keither5150]

Lewis, you are right to be confused..... There is basically two different stereo setups. Rick G and myself are the only testers so far. I will be writing up a post along with some videos to explain the difference between the two. The new stereo system has some advantages and the old has some advantages.
I will try to make sense of it for everyone soon.

[Lewis837]

😊 Classic engineering problem! No free lunches always trade offs. The great thing about GSA is that we get to see the inner workings and how complex some of issues are to solve. Can't wait to see the next step in the journey and how it helps or hurts in my particular setup.

I know you are a strong advocate for the stereo approach and the only thing stopping me from giving it more attention is the spacing of the cameras. I think you said you have 8 feet between the left and right ceiling mounted cameras and the other person (Rick G?) had 4 feet, I am a little under 4 feet because of the tee needing to be offset of the center line of the enclosure and the cameras needing to be symmetrically spaced form the center line. Is 4 feet the minimum in your opinion or do you think a smaller distance will work acceptably - assuming that in both approaches they need to be spaced symmetrically?

[COgolfengineer]

Oh interesting that the GPIO hardware trigger doesn't make a difference. Good to know.

Thanks for confirming that the sure fire way to trigger a camera is by using a LS camera, but the downside is the cost especially when that LS camera is just setting a trigger for a camera that's actually measuring ball info, it seems a little silly to spend that money on the LS.

Or you can take the LS cost and just go Stereo. It will be interesting to see the pros and cons and costs of VisTrak Vcam with LS trigger vs VisTrak Stereo. With the VisTrak Stereo, aren't the stereo cams triggered by a delay from the VisTrak camera? If so, I'm curious as to how it's more reliable than the VisTrak Vcam wihout the LS camera?