Session with Sony Smart Tennis Sensor

[Migelowsky]

Hi , I just bought the sensor , the truth ist that I just wanted a new toy.
But, after using it 2 times, I'm already interpreting and giving good use to the
data I get.
For example, my first session I notice that I was swinging a lot faster than a friend,
but the ball had less speed, That's because the amount of spin. On scale 1-10, it was
always about 8.
So , this time I went on the court, I was focusing on hitting more through the ball,
a lower trajectory shot. I won't abandon my high spinny shots, but I want to be able to
finish short balls and have more agressive shots.
Here's a video with that session. I had to make a screen record from my phone, because
the app at the moment doesn't hava an export option.

 

[v-verb]

Amazing feature! I have the Sony but have not tried the video yet

 

[sureshs]

So the sensor talks by Bluetooth to the phone app which is shooting the video so that the app can correlate the shot to the video?

 

[sureshs]

I can see coaches becoming obsolete. Previously you would have paid 80 bucks an hour to have a coach tell you to hit more through the ball, now you can figure it yourself.

 

[v-verb]

So the sensor talks by Bluetooth to the phone app which is shooting the video so that the app can correlate the shot to the video?

That's it

 

[Tennisanity]

Is it possible to correlate the spin number to RPMs?

 

[Migelowsky]

Is it possible to correlate the spin number to RPMs?

Not that I know, I think a 10 is about the same level as a pro tour player.
Positive numbers are topspin, and negative are slice.
Is more or less the same as Babolat Play, the measurements are compared to top 20 players. Zepp only knows if it's flat , topspin o slice.

 

[Booger]

So now what? How does this information lead to improving your game?

 

[Flatballs]

So now what? How does this information lead to improving your game?

Um, maybe start by reading the first post

 

[Tennisanity]

Would be good if you could get the spin numbers in real time so you can see immediately after a shot how good it was and then adjust things on the fly to improve the number.

 

[Migelowsky]

Would be good if you could get the spin numbers in real time so you can see immediately after a shot how good it was and then adjust things on the fly to improve the number.

They are real time, the thing is that they appear on the phone. With an apple watch may be possible, but it would be a bit uncomfortable to stop a check it every time you hit.
What I do, is after 10 mintues or when I need a break, I come and check the data and then try to adjust. I don't always use the live video mode because it would require a lot of space
for the video file, maybe just 2 10 minutes clips on my training session.

 

[Chas Tennis]

For the high level tennis serve, the ball impacts in the top half of the racket head more often.

Does the sensor work for serving?

Have you seen any data for high level serves or taken some measurements of your own serves?

For any stroke, if you take high speed videos showing ball impact location and compare them to the sensor indicated ball location, what is the accuracy?

 

[Migelowsky]

Yes, it works for serves.
Andy from Tennis Warehouse is an former tour player, check him doing some serves
on live video mode ( go to 5:38 )

Take a look at this site, the reviews are very detailed, they also have the Zepp and
Babolat Play.

http://www.tennis-technology.com/sony.html

 

[Chas Tennis]

Yes, it works for serves.
Andy from Tennis Warehouse is an former tour player, check him doing some serves
on live video mode ( go to 5:38 )

Take a look at this site, the reviews are very detailed, they also have the Zepp and
Babolat Play.

http://www.tennis-technology.com/sony.html

Frame near impact. This is useless for any evaluation of ball location at impact. Too much motion blur and I guess the ball is out of the frame.

Here is a frame as an example of what you need to evaluate the Sony Sensor for locating the ball on the serve or another stroke.

This frame has small motion blur and the high frame rate assures that you will catch the ball on the strings more than half the time. Some smartphones have little motion blur and high frame rates. You can catch the ball on the strings with lower frame rates but you will have to settle for catching the ball on the strings only about one in 10 serves.

Time on Strings / Time between Frames (at 30 fps)

3-4 milliseconds / 33 milliseconds -- about 1 in 10 serves catch the ball on the strings.

 

[Migelowsky]

I don't think I'm looking for that % of accuracy, just a general idea of were I'm making contact.
I'm just a club player, remember that this is a $200 dollar device
Maybe you'll find this interesting:

http://www.playsight.com/whatisplaysight

 

[GuyClinch]

This seems really cool. I am going to have to get one....

 

[Migelowsky]

Another feature =), motion shot.
With ball spin, swing speed and ball speed.

 

[5263]

I can see coaches becoming obsolete. Previously you would have paid 80 bucks an hour to have a coach tell you to hit more through the ball, now you can figure it yourself.

If it was that easy, he would already know and use both shots at the correct times. It's not like that info is not readily available here on TT.

 

[Migelowsky]

Everyone here knows all about rhs, angular rotation and a thousand more tt lingüo, and then I see
the video of some of the top posters playing.... . It´s not the same to know all about technique and to show it on the court.

5263 is right, that's the interesting thing about our sport, it's hard and we keep trying and trying to get better ( at least I´m ).
What I like about this tool, is that you get the confirmation right there, sometimes I thought I was
hitting flatter, but here I can see the exact shot and I realized that I wasn´t doing what I thought I was doing.

 

[julian]

Yes, it works for serves.
Andy from Tennis Warehouse is an former tour player, check him doing some serves
on live video mode ( go to 5:38 )

Take a look at this site, the reviews are very detailed, they also have the Zepp and
Babolat Play.

http://www.tennis-technology.com/sony.html

The part which you do not understand is like that:
You may know that a location of a contact for serve was not optimal
But one does not know how to improve the technique to change this location.
From this point of view (pun attempted) a sensor is second to useless.

 

[julian]

For the high level tennis serve, the ball impacts in the top half of the racket head more often.

Does the sensor work for serving?

Have you seen any data for high level serves or taken some measurements of your own serves?

For any stroke, if you take high speed videos showing ball impact location and compare them to the sensor indicated ball location, what is the accuracy?

Please read post number 20

 

[Migelowsky]

The part which you do not understand is like that:

??? I never said I want the sensor to be my teacher.
You think I want the sensor to say "hey, you are tossing the ball to far to your right and not using enough your legs" ??
"user, you are hitting late because you are overweight and not getting on time to the ball "

The task of the sensor is to give me data, knowing what to do with it ist my part.

 

[julian]

I

??? I never said I want the sensor to be my teacher.
You think I want the sensor to say "hey, you are tossing the ball to far to your right and not using enough your legs" ??
"user, you are hitting late because you are overweight and not getting on time to the ball "

The task of the sensor is to give me data, knowing what to do with it ist my part.

I am saying something much stronger: it is second to impossible to figure out which part of a serve motion to change to hit a ball on a serve closer to a tip of a racket. Try to think and experiment before you will post your answer.
So I am claiming that a location of a contact for a serve is practically useless.
Just to make it clear: I coach and play-so I have two angles to this issue.
For other reviews of sensors please google "tennisspeed"-his latest post is of interest.

 

[julian]

I

I am saying something much stronger: it is second to impossible to figure out which part of a serve motion to change to hit a ball on a serve closer to a tip of a racket. Try to think and experiment before you will post your answer.
So I am claiming that a location of a contact for a serve is practically useless.
Just to make it clear: I coach and play-so I have two angles to this issue.
For other reviews of sensors please google "tennisspeed"-his latest post is of interest.

The blog I am referring to is entitled "Part 11"-it is dated January 15 of 2015

 

[julian]

Frame near impact. This is useless for any evaluation of ball location at impact. Too much motion blur and I guess the ball is out of the frame.

Here is a frame as an example of what you need to evaluate the Sony Sensor for locating the ball on the serve or another stroke.

This frame has small motion blur and the high frame rate assures that you will catch the ball on the strings more than half the time. Some smartphones have little motion blur and high frame rates. You can catch the ball on the strings with lower frame rates but you will have to settle for catching the ball on the strings only about one in 10 serves.

Time on Strings / Time between Frames (at 30 fps)

3-4 milliseconds / 33 milliseconds -- about 1 in 10 serves catch the ball on the strings.

A location of a contact is not done via analyzing of a video.
The method is mechanical/electric,NOT optical,if I may use this phrase.
However in both cases data are second to useless from the coaching point of view.

 

[Migelowsky]

Thanks for the link Julian, I visited that site and many others before purchasing the gadget.
Do you find any positive aspect of owning one?

 

[julian]

Thanks for the link Julian, I visited that site and many others before purchasing the gadget.
Do you find any positive aspect of owning one?

The info about a speed of a ball for SERVE is ok.
Other data are very problematic/approximate.
I do NOT expect a situation to improve in a year or two because of instrinsic physical problems
which are very complex to explain
It is possible that a new Swiss product could be of some interest
I do not remember the name of the Swiss company-I put a blog about it.

 

[happyloman]

So the sensor talks by Bluetooth to the phone app which is shooting the video so that the app can correlate the shot to the video?

http://tt.tennis-warehouse.com/inde...th-sony-sensor-for-real-time-feedback.537936/

 

[brianmch]

Thanks for the link Julian, I visited that site and many others before purchasing the gadget.
Do you find any positive aspect of owning one?

The real question is whether _you_ find any positive aspect of owning one. From your starting post the answer would be yes. This device doesn't cover everything but seems to provide a few bits of info that can be useful.

It's nice to know what a thing does and doesn't do. The question of value/worth is related to how important those things it does are to the user. It has piqued my interest though.

 

[Migelowsky]

The real question is whether _you_ find any positive aspect of owning one. From your starting post the answer would be yes. This device doesn't cover everything but seems to provide a few bits of info that can be useful.

It's nice to know what a thing does and doesn't do. The question of value/worth is related to how important those things it does are to the user. It has piqued my interest though.

Hallo brianmch, yes I found it very useful and I'm enjoying it a lot.
There is a section of the app, that lets you set goal for "spin","swing speed" and "ball speed" of any stroke.
After my first sessions with it, I more or less found what is my "standard" or regular performance.
So, what I do is set a goal, for example: my average ball speed for my topspin forehand , I want it to be at least X mph. Without the sensor you more or less have an idea of how your performance was, but it's nice to see it in an "official way" and set it on record.

Live video mode is fun , I can look at my swing path and make the relationschip with the amount of speed I'm getting. I know that I have to swing more horizontally to have a flatish shot, but
again, it's nice to see it for yourself and have the data for the exact shot you are hitting.

I'm very happy with it, the only thing that I think needs implementation is an export feature. When I share the video, I have to use a screen recorder software, then edit it and upload it
to youtube or copy it via USB to my computer. I would like to have access to my info from any device.
If you have a friend with one ask him if you can test it , try it and see for yourself if it's worth it.

 

[Fxanimator1]

Hallo brianmch, yes I found it very useful and I'm enjoying it a lot...

Live video mode is fun ...

I'm very happy with it.

/\ This right here is reason enough to use it.
If it gets you out on the court more, you're going to improve. Filming your strokes and looking for deficiencies in your strokes or ways you can improve, is going to make you better.
No coach, or professional anything, is ever going to endorse something that cuts into their source of income.

 

[Migelowsky]

/\ This right here is reason enough to use it.
If it gets you out on the court more, you're going to improve. Filming your strokes and looking for deficiencies in your strokes or ways you can improve, is going to make you better.
No coach, or professional anything, is ever going to endorse something that cuts into their source of income.

There are some exceptions .My coach is considering adding one to track progress of his students, he regularly takes notes and video, so it is perfect for him.

 

[Fxanimator1]

There are some exceptions .My coach is considering adding one to track progress of his students, he regularly takes notes and video, so it is perfect for him.

That's a smart coach. Working with new technology rather than fighting a battle with it.

 

[monomer]

Hallo brianmch, yes I found it very useful and I'm enjoying it a lot.
There is a section of the app, that lets you set goal for "spin","swing speed" and "ball speed" of any stroke.
After my first sessions with it, I more or less found what is my "standard" or regular performance.
So, what I do is set a goal, for example: my average ball speed for my topspin forehand , I want it to be at least X mph. Without the sensor you more or less have an idea of how your performance was, but it's nice to see it in an "official way" and set it on record.

That is a good point and just one of the many useful features. I have one and so far have only used it a few times practicing serves. This alone has been worth it to me. Being able to try different things with my service motion and see the impact on speed and spin has been very helpful. I have found certain things I do that I thought added pace actually made my serve slower. I also found that I was taking more off my typical second serve than I thought (someone mentioned this in another thread also).

I haven't spent enough time with it yet but like the idea of being able to look at stat's over time and compare match play to practice.

Ball impact location is a nice feature but one that I don't care about.

The video export feature is awkward for non-Mac users. I have a Mac and it is pretty simple using Quicktime.

The big picture - this is an excellent tool if you have realistic expectations. I would expect improvements with each update to the app. I think it is the best of the sensors on the market and should force other mfg's to improve theirs. It is exciting to think what will be available in 5-10 years.

 

[brianmch]

Interest piqued for sure!

 

[julian]

/\ This right here is reason enough to use it.
If it gets you out on the court more, you're going to improve. Filming your strokes and looking for deficiencies in your strokes or ways you can improve, is going to make you better.
No coach, or professional anything, is ever going to endorse something that cuts into their source of income.

The news is that a Sony sensor is not even close to compete with a coach.
At this moment it has three useful features:
A video recorder
A serve speed measuring device
A data storage device
Very little to help with a forehand or a backhand
You are free to use it because it is a free country but you may go astray

 

[Fxanimator1]

The news is that a Sony sensor is not even close to compete with a coach.
At this moment it has three useful features:
A video recorder
A serve speed measuring device
A data storage device
Very little to help with a forehand or a backhand
You are free to use it because it is a free country but you may go astray

So you're saying that recording your strokes is useful, but helps very little with analyzing your forehand or backhand?
That is so contrary and illogical.

 

[Migelowsky]

The news is that a Sony sensor is not even close to compete with a coach.
At this moment it has three useful features:
A video recorder
A serve speed measuring device
A data storage device
Very little to help with a forehand or a backhand
You are free to use it because it is a free country but you may go astray

Out of curiosity, what would you fill your necessities? it doesn't matter that it doesn't exist now or that it might never exist.Just let your imagination fly,
a Robot with exceptional IA ? Nothing will ever replace a coach, but you are one, right ?so as a coach, what would help you develop better players?

 

[Fxanimator1]

Out of curiosity, what would you fill your necessities? it doesn't matter that it doesn't exist now or that it might never exist.Just let your imagination fly,
a Robot with exceptional IA ? Nothing will ever replace a coach, but you are one, right ?so as a coach, what would help you develop better players?

I'll answer that for you Migelowsky... video. You need the player to be able to see his/her own strokes, so they can see and understand what to change.

 

[julian]

Out of curiosity, what would you fill your necessities? it doesn't matter that it doesn't exist now or that it might never exist.Just let your imagination fly,
a Robot with exceptional IA ? Nothing will ever replace a coach, but you are one, right ?so as a coach, what would help you develop better players?

Current sensors do not allow to measure well three variables of a incoming ball:
1.a speed of an incoming ball
2.an angle of an incoming ball
3.spin of an incoming ball
The important word above is "well".
Some problems are related to physics/mechanis,some related to electronics,for example a sampling rate
of a device
So information provided is very limited/approximate.
As I have said tennisspeed indicated some limitations so I am not only pointing these limitations.
There are one additional problems related to mathematics/computer science for 3d trajectories of Zepp.
Sony so far does not have these problems simply because they did not attempt to generate 3d trajectories
as Zepp did.

 

[Heisenberg]

I would get so much more out of a sensor that essentially tracked a match. Like what type of shot was played and what position in the court, and gave you all the typical stats (eg: first serve %. winners, errors, winners at net).

At the moment the only way to do this is to video and look back later, or get someone to look on and do it.

Surely this is around the corner.

 

[Flatballs]

Current sensors do not allow to measure well three variables of a incoming ball:
1.a speed of an incoming ball
2.an angle of an incoming ball
3.spin of an incoming ball
The important word above is "well".
Some problems are related to physics/mechanis,some related to electronics,for example a sampling rate
of a device
So information provided is very limited/approximate.
As I have said tennisspeed indicated some limitations so I am not only pointing these limitations.
There are one additional problems related to mathematics/computer science for 3d trajectories of Zepp.
Sony so far does not have these problems simply because they did not attempt to generate 3d trajectories
as Zepp did.

I have used a Zepp, for a sensor device it makes a good substitute for a missing chess piece.

 

[julian]

There is a lot of feedback from users in sections describing a Babolat sensor,a Zepp sensor and a Sony sensor.
The feedback comes from real users-some of the feedback is much more negative than mine

 

[GuyClinch]

Current sensors do not allow to measure well three variables of a incoming ball:
1.a speed of an incoming ball
2.an angle of an incoming ball
3.spin of an incoming ball

Less compelling then it sounds..these negatives. RHS major factor - and the sensor measures these really well. When they rolled out the radar to compare - it was fairly accurate..

 

[julian]

Less compelling then it sounds..these negatives. RHS major factor - and the sensor measures these really well. When they rolled out the radar to compare - it was fairly accurate..

For the record radars generally do NOT measure RHS-they measure a ball speed

 

[JK1]

Is it possible to correlate the spin number to RPMs?

Did you get an answer on this? I too am confused how to convert ball spin to rpm. Thanks!

 

[GuyClinch]

Did you get an answer on this? I too am confused how to convert ball spin to rpm. Thanks!

This seems impossible. Likely the sensor monitors racquet face angle and stroke path and stroke speed (maybe) and calculates the +/- from that. much like ball speed this would be impossible to perfectly calculate without knowing things like string type and spin of incoming ball.. THis does not make it useless though. if you are swinging fast and hitting big +/- numbers I have no doubt your balls will have plenty of spin..

I love to see how pros would fare on this sensor..

likewise because it does not know the incoming ball speed it can only guess at the outgoing speed of the ball - but its an educated guess because it knows racquet face position and racquet swing speed..(as well as racquet face angle)..

 

[AMGF]

Anyone knows how sensor readings for ball speed correlates with real life speed measurement (radar)?

My question is, if I hit two serves, one with low tension gut and one with high tension poly, the ball will go much faster with the gut. Can the sensor feel that or it just approximates ball speed through racquet speed?

 

[GBplayer]

Do the numbers generated by the sensor change if you add lead to the racket ?

 

[skuludo]

Do the numbers generated by the sensor change if you add lead to the racket ?

No, it was the same speed. My swing speed changed at first with the added weight. Then eventually my swing speed became the same swing speed was as fast as a stock racket. The max ball speed was the same whether with added weight or none.