Every graphic I saw online was either outdated or didn’t go back far enough, so this is my attempt to put a more comprehensive one out on the internet. I have 2013 through 2023 on here, and will update as I find old ones in the woods.
A polynomial regression was used to fit these trajectories to a polynomial function, and this regression function was solved for f(x) when x = 250. The input x being distance, and f(x) returning the ball’s altitude (in yards) at that distance. TopGolf nets measure 50 yards high at 250 yards, so if f(250) > 50, the ball will clear the net
This polynomial regression step was because I couldn’t figure out how to pull the function out of the ball flight model, however our fit line’s r² was 1.00000 so I am not losing any sleep over it
TopGolf balls do not behave the same as regular golf balls. Based on Trackman 4 data I reported here, off driver the ball speed is 4.6% lower, launch is 6.1% lower, and spin is 28.6% higher. These data match my anecdotal experience at TopGolf (I’m not a walking launch monitor but I can tell spin was high and speeds were down a bit). Simulations will be ran using these modified numbers, as these changes in trajectory have a quite significant impact on distance, apex, and the potential to knock one out of TopGolf.
His ball intercepts the net at 10.0 yards of height. Closer!
Typical / good drive from Rory McIlroy:
As of March 12th, 2023, Rory’s average driver ball speed in competition is 184.6 mph. In 2017 Rory tweeted his launch monitor numbers, including a ball speed of 184.1 mph, so I think this is a good enough approximation of his current average. This likely represents a better than average strike given the carry and total.
Ball speed: 184.1 mph → 175.6 mph with TopGolf ball
Spin: 2523 rpm → 3245 rpm
Launch: 12.5° → 11.7°
His ball intercepts the net at 34.1 yards of height. The first to threaten it!
This shot would have carried 297.9 had its flight been unobstructed. Had it been a normal ball rather than a TopGolf ball, this carry would have been 320-330 at sea level.
OK, What if Rory brought a TP5x or ProV1 to TopGolf and hit that, and he’s also on the 3rd floor??
Same input parameters as above, I just did not apply the speed / spin / launch penalties of a TopGolf ball
184.1 mph, 2523 rpm, 12.5° launch
I made the assumption that the hitting surface of the top deck is 30 feet from the ground level. It may be higher but I do not have any numbers on this.
Just mere inches short!
Great strike from 2022 World Long Drive Champion, Martin Borgmeier:
TopGolf balls do not go as far as typical golf balls
For me, carry distances were down 8%
There are multiple reasons why it is advantageous for them to do this
Methods and materials:
Trackman 4 was used, indoors, with about 12 feet of unobstructed flight. All data were normalized to sea level and 75 °F.
A single TopGolf ball was used, which certainly limits the validity here. For what it’s worth I did not steal it, for some reason my driving range has a few random TopGolf balls that occasionally find their way into our buckets. So I guess I did steal it, just not from TopGolf. Regardless, I plan to throw it back on the range next time I hit a bucket to alleviate this crushing weight on my conscience.
A RCT ProV1x was used (what is RCT?), as this was Trackman and it’s difficult to get spin readings without a RCT ball.
To ensure the ‘input’ was close enough to make a fair comparison, I ensured clubhead speeds were equivalent in both groups. I excluded several early PW shots as there was a warm-up bias where I was swinging a few mph slower at the beginning of the session. After the exclusions, the clubhead speeds were nearly identical at 76.4mph and 76.5mph in the two groups. Club path, face to path, and angle of attack were consistent within the groups as well, as AoA especially would influence backspin. I excluded one data point from the driver ProV1x data, where I swung a few mph faster.
There was only about 12 feet of unobstructed ball flight for Trackman to read. Of note, Trackman gave me several italicized spin numbers with TopGolf balls (italics means spin was not actually measured but only estimated based on impact conditions – i.e., italics = less accurate – more info here) I did not get any italicized parameters with the RCT ProV1x.
This means the spin accuracy is questionable. Indoors, this is difficult to avoid. As discussed above, I only had one TopGolf ball to use.
Results can be seen in the images at the top of this page.
This provides context to the observation that many of us have made when we go to TopGolf, which is that it feels like the ball doesn’t go anywhere.
Results reflect what I have seen in many range balls, which is more spin off of woods, less spin off of irons or wedges. Had I hit my 56°, I suspect spin would have dropped from 10,000 to something like 8,000 rpm. A slight penalty on ball speeds as well. Anecdotally, I have seen about a 5% ball speed dropoff from range balls to TopGolf balls, however I’ve never had the chance to compare a premium ball to TopGolf.
I find this information useful because it plays into the argument of whether one can drive a ball over TopGolf’s back net. I hope to follow up with another post on that, but the limited flight of TopGolf balls becomes quite relevant here.
Why is this the case?
Golf balls meant for course play and golf balls meant for repeated usage on a driving range have fundamental differences in design. Balls meant for play on a course (we’ll call them “premium balls”) are optimized for launch and spin to provide the best performance. The urethane covers on these premium balls, while providing the best trajectory and spin profile, are soft and cannot stand repeated impacts. Balls for driving ranges (and TopGolf) are built less for performance but instead for survival – they have essentially the hardest, most durable covers feasible, to ensure their survival over thousands of impacts. For some driving ranges, balls are replaced annually or even less often.
In addition, premium golf balls’ cores are once again designed to optimize launch and speed. TopGolf balls require the inclusion of an RFID chip in their plastic core (see image below!). This foreign, non-homogenous core almost certainly is less efficient than a normal core, and ball speeds will take a hit compared to balls that do not necessitate the inclusion of chips.
Finally, it suits TopGolf from a business perspective to have limited flight golf balls. Even without RFID chips, some driving ranges choose to use limited flight golf balls, which are designed to be slower, to save space. Driving ranges with real estate limitations use these often. A TopGolf range is expensive to construct, and needing 250 yards of range and fencing saves costs over a 350 yard range, which might be typical for a normal driving range.
I compared the Mevo ($400) to the current gold standard of doppler radar launch monitors, the Trackman 4 ($19,000)
The Mevo performs extremely well for ball speed (on any given shot, less than 1% off)
The Mevo performs very well for club speed (usually less than 3% off)
The Mevo performs pretty well for carry (usually less than 5% off)
Spin and launch angle are highly erratic and are almost unusable (20-60% off)
Below are the simplest and fastest graphs to summarize the accuracy:
The Mevo ($450) is a portable radar launch monitor, which uses Doppler radar to measure different parameters of a golf shot. There is a wide variety of launch monitors at various price points, but at the top end for radar models is the Trackman 4 (starting at $18,995), which is the gold standard I used for these tests. Owning one is impractical for almost everyone outside of pros and coaches, but thankfully they can be rented for $30/hour where I live. I spent a couple sessions hitting on one and comparing its read of each shot to the Mevo. Both devices were calibrated for the altitude I usually play at in Akron (1,000 ft. above sea level).
Data was collected indoors with 8 feet of unobstructed ball flight. Reflective metallic stickers were used on each ball to improve accuracy, per the recommendations of Flightscope. I used Taylormade TP5x’s for all shots. I include “2022” in the title because a disgusting amount of data interpretation happens behind the scenes with these companies and their proprietary calculations, and Flightscope’s firmware updates improve accuracy even as the hardware remains the same.
I think it’s realistic to break this down to two parts – accuracy for individual shots, and accuracy for club gapping purposes (i.e., looking at averages for 5-10 shots with each club). For the latter, if someone hits 10 shots with each club, the individual variation doesn’t matter as much so long as the averages are close to the true (Trackman) averages. So for individual shots, I’m going to avoid using “average % error” as that could smooth out any nuance if the Mevo mixes over-reads with under-reads – it would improperly return a value very close to zero. I’ll use the absolute value of % difference on each shot. I’ll show the % difference for individual shots for a couple sets of data (there is too much data for this to be practical for each shot and club). For session averages, these will be true averages.
Below is some of the raw data after I pasted everything from both Trackman and Flightscope’s websites to Excel:
Results: Comparing session averages (5-15 shots with each club)
Results: Comparing the parameters for individual shots:
For 16 swings of a driver, I compared the ball speed (mph) that Trackman measured and the ball speed that Mevo measured. Below is the percent difference from Trackman’s speed that Mevo’s measured on these 16 individual swings. The Mevo never missed a shot and never differed by more than 0.8%. On average, it slightly misread on the high side. It is important to point out that the differences here are extremely minute – the session average on Trackman was 149.2mph, whereas Mevo’s was 148.8mph. This difference is too small to have any actionable impact, even on a professional fitting.
Below is the same data for the other parameters:
Results: Average difference from Trackman (Abs):
As discussed above, I think using the absolute value of the difference from Trackman on each individual shot is a fair way to gauge “how far from the true value might this be?” when you are using your Mevo on the range and receive a carry distance or ball speed. So below is the average of this difference on each shot:
Mevo performed admirably given the price point and its competitors. Its ball speed measurements are effectively indistinguishable from Trackman. At 160mph, a 0.5% difference would be reading 159.2-160.8mph, which is not significant enough for anyone to care about, outside of robotic equipment testing. Club speed is largely consistent, if slightly more inaccurate. Launch angle was consistently over-estimated. Spin was highly erroneous. Carry is influenced by spin and launch, and poorly read spin numbers influenced carry distance at times. To give an example, here is a tale of two reads with a 4 Hybrid shot that I struck thin:
The gruesomely over-estimated spin and launch lead to a low carry distance, even though Mevo nailed the ball speed.
I think the best use of the Mevo is if you have some sort of baseline familiarity with your launch monitor numbers, particularly ball speed. For people trying to build swing speed, ball speed is an important parameter to watch when using your driver. And the Mevo’s ball speed is effectively indistinguishable from your true (Trackman) ball speed. If Mevo reads a spin of 6,000rpm on a well struck driver shot, it is useful to be able to say “I know that’s not true” and throw out the carry distance, which would be skewed, while understanding the ball speed is still fine to interpret.
Trackman isn’t infallible, and even though it was treated as the ‘true’ values, it’s only an estimate. In indoor settings some professionals prefer photometric launch monitors (e.g., GC Quad). Its true strength lies in outdoor use where it can track the full flight of a shot. As these tests were performed indoors, they are limited. However Trackman likely represents the technical limitation of Doppler radar launch monitors as of 2022, and my goal was to see how close a $400 device can come to this standard.
I also wonder how the prescence of more than one radar device affects reading. These units are effectively floodlights, however instead of visible light from a bulb, it’s longer radio waves emitted from an antenna (or in the case of Trackman, an array of multiple antennae at different frequencies). I wonder if the additional radiation from Trackman would actually improve the performance of the Mevo, which is normally limited by its small size and its meager power as a battery-operated device. If anyone has experience in signal processing and has insight… feel free to email me!
I will add more data with irons this fall as I have time.