Sony Mocopi Review: Promising VR Mocap Tracking With Limited Functionality

Accessible full-body tracking may well be the next big thing for the AR/VR market, and a number of major companies are working on ways to get more than your headset into the Metaverse. Sony is one of those companies and has gotten its foot in the door early with its Mocopi sensors. They were unveiled in Japan back in 2022 and have finally been released in the United States.

The set Sony is selling for $449 consists of six sensors that you attach to different parts of your body.  Two units are meant to strap onto your ankles, two more are meant to strap onto your wrists, another unit clips to your waistband, and the last one goes on your head. From there, the sensors sync with a phone via Bluetooth, and their tracking systems let the phone app know where all of your limbs are. The sensors charge via an included case, though it doesn't come with the necessary USB-C cable. 

Straps are included too, and fully charged, the sensors can run for around 10 hours. It all runs through an app that is available for both iOS and Android. Sony provided a set of Mocopi sensors for the purposes of this review. We tested features like the Mocopi's motion capture capabilities and explored its space in the current VR scene. 

If you've had any experience with full-body tracking systems, you know they can be an absolute nightmare. Take the Vive Tracker for example, you have to set up a bunch of towers, then plug in a bunch of dongles, then calibrate everything, then troubleshoot for hours as everything will in fact go wrong.

Mocopi is a little bit like that but far simpler. You need to connect all of the sensors to a phone via Bluetooth and Mocopi's app. For us, the initial connection was fine but then came the firmware update which resulted in constant errors. Tapping retry on every sensor was almost like a mini-game. It took several attempts and multiple restarts of the app to get the update through. This may be a teething problem and something to do with the app being in beta, but it is certainly frustrating.

When things eventually get going, calibration can also be a little hit-and-miss. It involves standing straight, then taking a step forward when you feel the phone buzz. Somehow this fails pretty often. The good news is that — once paired — it is a lot quicker to reconnect the sensors. All in all, a frustrating, glitchy, mess — but it's still in beta and this is to be expected from current full-body trackers.

Anyone who has played around with VR equipment will be aware that some of it is quite temperamental. Headsets and controllers with inside-out tracking tend to rely on cameras to work out their positions and orientation. Similarly, tower-based trackers, like the ones sold by HTC, need a clear line of sight between themselves and said towers. Mocopi trackers don't rely on towers and have no external cameras. Instead, after calibration, they guess their current position based on an algorithm, movement, and possibly their proximity to other trackers.

This is a huge bonus if you need to do something while wrapped in a blanket or in extremely poor lighting conditions. The latter, especially, is surprisingly common. Sometimes, when the sun goes down the lights in your house just don't cut it for VR or AR. They can either be too bright, or too dark; either way, your tracking is going to suffer. Not with the Mocopi trackers. Infrared controllers need a line of sight with your headset to avoid loss of tracking, Sony's trackers don't. You can put your arms behind your back and the trackers will still know what's going on. Mocopi also works outside, which is an area where many VR devices will struggle or risk catastrophic damage. 

The Mocopi is currently a great choice for indie game developers, filmmakers, YouTubers, and other people interested in basic mo-cap. It isn't going to give you the same level of accuracy as professional motion capture, but it isn't going to set you back thousands of dollars either. In our experience, the accuracy is what we'd describe as "close enough." It isn't to the millimeter precise all over the body, but the on-screen avatar does give a very clear indication of what the person wearing the sensors is doing. They give a great representation of where your body is 99% of the time.

We may have found another use for the trackers too. The setup is particularly handy in many sports, as you could theoretically use Mocopi to keep track of your form. It's very good for shadowboxing, even if that involves fairly quick movements. You can concentrate on what you're doing, then roll back on the footage later to make sure your footwork is spot on, your rear hand isn't dropping when you jab and your chin isn't sticking out. You could apply it to pretty much any sport that requires full-body movement and good form. Though we didn't extensively test it, the Mocopi did seem to track a couple of attempts at a golf swing well.

"VR Chat" may be a big selling point for Mocopi. Its hardcore users value immersion and would love a reasonably priced way to enhance their avatar and role-playing capabilities further. You can totally see why Sony targeted this particular game. Its audience will really appreciate it, they're the sort of people that will splash out for this sort of accessory, and a little bit of latency won't ruin their experience. 

Unfortunately, its performance in "VR Chat" does demonstrate how there is a way to go before you'll see something like this in mainstream VR games. In rooms with a limited number of users and low ping, the tracking worked great. It was surprisingly fluid, especially considering the calibration issues, and we could make our avatar do whatever pose we wanted it to. In the "home" room, there was seemingly zero latency, which is outstanding considering the signal is pinging from the trackers to a phone to the WiFi network to the headset. 

You'd really expect some kind of delay there, but you're unlikely to find it in an empty server. Problems arise when you go somewhere with people. While the main game doesn't suffer, a crowd creates notable lag from the Mocopi sensors. Movements happened seconds later in some cases. Then there are the connection issues. 

The system stopped tracking legs roughly three times per hour. At first, it was a bit confusing, but a quick glance at the phone showed the trackers had disconnected. The trackers can be reconnected and recalibrated even without taking the headset off, proving it's fairly straightforward once you get used to it. It's still something that needs improving, though.