The Head Tennis Sensor is the first sensor released from the sporting manufacturer. The sensor is a small Inertial Measurement Unit (IMU) sensor placed inside the bottom of the racket’s handle. It is powered by Zepp tennis, which made two iterations of their own sensor with the first released back in 2014. The purpose of this post is to review the Head Tennis Sensor and its usefulness in adding to the learning, development and social aspects of the tennis player. The Head Tennis Sensor was used in conjunction with the Head Extreme MP tennis racket during the testing.
The Un-Boxing
The product comes in a tidy package shown below with main components: IMU Sensor, Head key, power cord with magnetic power connector end, quick start guide and manual.
Picture: Boxing of the sensor. Below: Exploded view of components in box with sensor in the centre. The main screen of the tennis sensor app is on the right.
Before starting, it is required to download the Head Tennis Sensor app from from the Appstore or Google Play store.
The Set-up
Replacing the bottom cap with the sensor was fairly simple using the Head key provided. A sneaky trick I noticed when changing it over, is that the original cap on the bottom of the racket came with an additional small weight attached to the cap (total 6 grams). I assume this is to make it the same as the sensor weight of 6g so it feels like the same racket. I decided to have a look at the cap on my previous racket model Head Extreme Graphene 360 and when popped out the cap I could see that it had no additional weight added to it and was considerably lighter at 2g. I think the best thing to note is that the sensor is all on the inside making it straight flush to the bottom of the handle instead of it protruding like the Zepp predecessor.
Photo: The bottom caps for the racket i) Head Tennis Sensor ii) Cap with weight from the original racket iii) Plastic cap from previous model racket without weight
Charging is the first task to complete and it was very simple to do using the chord that was given in the box. Head have decided to use the magnetic connector to the sensor for charging which makes it simple. I believe this is an advantage over a normal micro USB as it doesn’t have to be inserted into the racket or cover any holes. Note: a usb power adaptor will be needed to plug into a power socket.
Photo: Magnetic charger connection to sensor
Connecting the sensor to the app was pretty straightforward. I begun by pressing the connect sensor button on the app. To activate the sensor, I shook the racket which led to the sensor list popping up. I like what Head have done by adding the shake feature, as it made it really simple to connect to the mobile device almost immediately. The next step was to add the model of the racket I was playing with, which was prompted by a QR scanner. It’s quite nifty to see the QR code hidden on the racket near the throat of the racket. When the scanner found it, the racket with all the model specific information was automatically added in.
Photo: Shake to activate sensor and following sensor popped up.
On Court
After set up, it was time to take the sensor onto the court for a hitting session. What I enjoyed most was that the sensor caused no hindrance to my game. It felt like I could just focus on tennis and not get too distracted by the sensor, as the information is transferred by bluetooth to my phone that is sitting on the side of the court. With the addition of the small weight with the original cap I thought the sensor was fairly similar to play with. I looked at the stats during my rest periods on the side of the court and all the information was instantly there when I opened the application.
Photo: The sensor is neatly inside the racket and has minimal effect on groundstrokes and serves.
Without going into too much detail the stats look fairly accurate with ball park figures. Head have three different metrics for every ball – Speed, Spin and Heaviness. I don’t really know what heaviness is, I assume it’s the amount of impact and degree of difficulty for the receiver. This might be formulated from the speed and spin. Each sessions data could be easily stored on the given calendar within the app which was pretty neat. At the end of the session all details can be shared with a photo from the session to any social media platform.
In the total session the battery went down 10% to 83% in an hour so that’s a pretty decent battery consumption rate. The sensor was able to send stats to my phone from both ends of the tennis courts, so the distance I could stand away meant I did not need to move my phone from end to end as I played.
Extra features
The impact location on the racket was a good additive. It showed where abouts the ball was impacting on various shots and even showed the time where it was a framed hit. However, sometimes I found the impact location to be the same for every ball which it wasn’t. Also some were classified as frame hits when I thought it hit the strings.
There was also some good training tools to help learn and discover new techniques about tennis. This was in the form of a library containing videos and demonstrations of different shots. Once placed in training mode some of these drills can be practiced for eg forehand topspin crosscourt x 10. This pocket coach can be used when practicing away from your coaching session with some feedback.
There is also a fun aspect on the competition feature about playing against another person with the sensor. As I only had one sensor I didn’t get a chance to test this out though something I would like to try in the future.
3D motion swing was a great way to see the way you are serving in a 3D view. This covers ever instant the racket moves on any axis from when you start your service action, ball toss and racket behind the head it all picked it up. It also showed where the where in 3D the ball was impacted. The below table shows a break down of the different serves from each side.
I think the 3D practice serve feature has lots of potential. It’s great to see the service action from each angle and even shows you the impact with the ball in white. I can see differences in swing styles probably the most from the back position and I think it is great to see it. However, for the average person who has this sensor they are going to find it hard to interpret what it means and how you can improve. It did not track the follow through very well stopping quite early on. If I was a normal coach trying to teach a student a new serve style i’m sure they can pick up on these details by watching them with the naked eye. I guess where it comes useful is that if you want to train yourself without a coach.
The other problem is i’m still very unsure of the accuracy and precision this is exactly where the sensor goes. This is why I think it will be more difficult for top level tennis players to use and differentiate between other top players. Unfortunately the 3D images couldn’t be saved to the calendar.
Conclusions and recommendations
There is no doubt the Head Tennis Sensor powered by Zepp has improved since the first iteration of Zepp. Having the Sensor inside the racket makes this really neat and attractive to any tennis player looking to improve their game.
I still feel like the metrics of speed, spin and number of shots is used as a tracker. Like fairly similar to your daily steps. It’s nice to know but I would rather just focus on learning a better technique or getting fitter. I think this is good for a coach to use as a tracker on their students to make sure they are hitting a certain amount of balls per week. I still think for these reasons the sensors target market will primarily to those people who are at an intermediate level who have a decent interest in tennis. It could also be used for more social players of tennis who can use it as a self-coach with useful tips and techniques. The recommended retail price of the Head Tennis Sensor is around $179.99.
Have you used the Head Tennis Sensor before? If yes, do share your own experience in the comments below. Or feel free to reach out if you would like to find out more.
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