Thank you for your continued support of Uni-motion.
We recently hosted our second ‘Uni-meeting,’ and we want to extend our sincere thanks to everyone who joined us.
We’re thrilled to have brought you an even more exciting and enhanced experience this time around. We hope you enjoyed it!
For those who couldn’t make it or want to revisit the event, we’ve put together a concise summary of the highlights from the second ‘Uni-meeting.’ Be sure to check it out!
We were also honored to have a special guest, Hiro, a full-body tracking researcher and writer, who joined us for an in-depth conversation with our developer, Yuki Mirai.
Hiro: “Hi, I’m Hiro. I write about full-body tracking on my site, ‘Hiro’s Lab Notes on Full-Body Tracking.’ I’m here today as a volunteer. Thanks for having me!”
Table of Contents
- Q&A Corner
- Special Talk: Yuki Mirai ✖️ Hiro
- New Information & Announcements
Q&A Corner with Uni-motion Developer, Yuki Mirai
Q: Do you have any plans to create a Uni-motion group on VRChat?
We’re excited to announce that the official Uni-motion group has now been launched on VRChat! This is a space where users can connect, share experiences, and enjoy exclusive content from us.
Feel free to join using the following link:
Q: Who is Uni-motion intended for?
Saying ‘people who want full-body tracking in VR’ seems too broad.
I think highlighting ‘long-lasting performance with decent accuracy’ would be a strong point. What do you think?
You’re absolutely right—saying “for people who want full-body tracking in VR” is indeed a bit too broad. The key selling points of Uni-motion are that while it may not match the accuracy of optical trackers, it offers consistent performance over long periods and doesn’t require setting up base stations.
Hiro:
One of Uni-motion’s biggest strengths is its user-friendly setup and interface, especially for beginners. I was amazed at how quickly I got everything up and running.
That’s a great point! We’ll definitely highlight the ease of use as a key feature in our future promotions.
Q: It would be helpful to have a summary of the tracking differences between the services it supports.
Currently, Uni-motion works with VRChat, Cluster, Virtual Cast, etc., but I notice differences in usage and calibration between them.
We’ve noticed this during development as well. We’re planning a website update soon, and we aim to include videos and other resources that highlight the differences in performance across these platforms.
Additionally, if possible, we’d like to include tips for calibrating Uni-motion for each service in the user manual.
Please stay tuned for the website update—thank you for your patience!
Thank you to everyone who submitted questions!
(Left: Host Unimo-chan, Right: Developer Yuki Mirai)
Special Talk: Yuki Mirai ✖️ Hiro
We had an engaging conversation covering various topics related to Uni-motion and VR.
Q: What are the differences between optical and IMU tracking?
Q:Is IMU tracking easier to set up?
(Hiro): It’s not so much that IMU tracking is easy, but rather that Uni-motion makes it easy. With other systems, it can be quite a hassle. The toughest part is when you’re alone, having to take off your VR headset and deal with troubleshooting in the real world.
(Yuki): That’s something we’ve improved along the way. We’re continuously making changes to make it even easier. With optical systems, the setup can be a bit more complicated.
Q: Is optical tracking cumbersome?
(Hiro): The biggest hurdle is having to secure a play area. You also need to position the base stations correctly, and they can break down about every two years. If there’s a shortage of replacement parts, that can be a real headache…
(Yuki): That’s a significant issue. The cost is one thing, but if you can’t get replacements, you’re out of luck. Base stations have motors inside, so they tend to wear out faster. It would be great if we could just replace the motors easily, but that’s not usually the case. Uni-motion doesn’t have moving parts, so as long as the circuit board isn’t damaged, it should last a long time.
Q: Is the accuracy of IMU tracking subpar?
(Hiro): Among consumer devices, it’s not the best, but it’s not the worst either. It would be great if more people were inspired to create or tweak their own devices, like how Yuki Mirai started, but not everyone is like that. Those who want to capture detailed expressions tend to choose Vive trackers.
(Yuki): Exactly. As a developer, it’s tough to admit, but if you prioritize accuracy, Vive is currently the go-to option. We can’t sugarcoat it. As mentioned earlier, IMU systems are currently about “long-lasting, decent accuracy.” Since there’s a limit to how much the sensors can improve, we’ll need to supplement with new sensors and ideas. But adding more sensors to boost accuracy can make the system less user-friendly.
Q: What’s the difference in the number of required devices between systems?
(Hiro): For full-body tracking with optical systems, you need an HMD, controllers, and three additional devices. In contrast, IMU systems often require more attachment points. Many people, especially beginners, may not understand why so many are needed.
(Yuki): Good point. Uni-motion calculates positions primarily based on sensor tilt. Using a technique called forward kinematics, we calculate positions sequentially—head, chest, waist, knees, and ankles. If any intermediate data is missing, the calculations can’t be done. Different companies might use different methods, but fewer sensors generally mean less accuracy.
Q: Supported HMDs and compatibility
(Hiro): It’s crucial for manufacturers to announce supported HMDs and provide official support.
(Yuki): Some companies seem to want to keep everything in-house, developing exclusive trackers along with their HMDs. This “political” aspect leads to less compatibility between devices from different companies. Third-party full-body tracking systems need to keep up with an increasing number of HMDs, which is challenging. These companies also face pressure to keep prices low, making things even tougher.
Q: Price considerations
(Hiro): I managed to build a full-body tracking setup with a used first-gen VIVE set and three trackers for around 90,000 yen. A new setup today with three Vive trackers and two base stations costs about 108,000 yen. If you want to keep it under 100,000 yen, you’ll have to go the used route.
That’s why Uni-motion, offering 6-point tracking at a lower price, stands out.
My research shows that people who are completely new to full-body tracking are typically willing to spend around 30,000 to 40,000 yen. Those who do their homework and save up usually end up buying Vive trackers. The temptation to spend on avatars or other things in VR can be strong, making it hard to save up for full-body tracking.
(Yuki): That’s true. Avatar costs can add up quickly. We’re committed to finding ways to provide affordable yet high-quality devices.
Q: How can we increase the number of full-body tracking users?
(Hiro): My interest in full-body tracking started when I saw someone who recorded themselves for 14 days straight to train a machine learning model for posture estimation. It amazed me that someone would expose their personal life to develop this technology. I believe real-life experiences, like trying full-body tracking at events, are crucial for its growth. I think Uni-motion’s effort to build a community in VR is very forward-thinking.
(Yuki): That’s an interesting entry point. I was also impressed by that person’s camera tracking; it felt revolutionary. Although, it did make me think, “If it works without sensors, we’re done for!” Ultimately, though, camera tracking has its own pros and cons.
Exhibiting at events like Virtual Market is great for letting people experience full-body tracking firsthand. We plan to strengthen both our VR and real-life communities.
Q: User communities for full-body tracking
(Hiro): It’s rare to see user communities dedicated to specific devices. While there aren’t many formal communities, full-body tracking discussions are common in the VRChat community.
(Yuki): That’s a good point. For example, I’m into folding bikes, and the famous manufacturers often host owners’ meetings. I’ve been thinking about creating something similar for Uni-motion through Uni-meetings.
Regarding increasing full-body tracking users, supply issues were a major hurdle in the past.
Q: Device supply and pricing issues
(Hiro): Supply issues, especially with IMU systems, are less of a concern now, but price competition has become more intense.
I’ve noticed that Uni-motion’s recognition among international users is still relatively low. When I posted pictures of various devices online, people asked what Uni-motion was. As awareness grows, costs should naturally come down.
(Yuki): You’re right. Semiconductor supply has improved, so the supply issue has largely been resolved. However, the low international recognition is something we’re currently struggling with. We’ve started taking steps in the streaming community to raise awareness.
Q: Thoughts on avatars and full-body tracking
(Hiro): Avatar support for full-body tracking has become the norm, but what’s your vision for full-body tracking, Yuki? On my site, I define “full-body tracking” as tracking 6 to 11 points on the body.
However, recently, people have also started expecting facial and eye tracking. It might be time to redefine what we mean by “full-body tracking.” What’s your goal for the future in terms of tracking and integration with avatars?
(Yuki): It’s great to see more avatars supporting full-body tracking.
As for future goals, ideally, we’d like to track even the smallest details, like skin folds or hair movement, though there are limits, of course (laughs).
More realistically, we’ve been considering finger and eye tracking that could be used with devices like the Quest. Unfortunately, we haven’t been able to tackle that yet due to the challenges of bringing a stable product to market. Meanwhile, other companies have released products similar to what we had in mind.
To enhance immersion, reducing the number of wearable devices while maintaining accuracy is something we’re also considering. For now, our focus will be on improving Uni-motion and potentially developing something like a ‘Uni-motion 2.’
Q: What makes full-body tracking so appealing?
(Hiro): In VRChat, communication goes beyond words, allowing for full-body expression. Full-body tracking lets you immerse yourself in a world you couldn’t experience before.
(Yuki): Absolutely. The biggest draw is the immersion.
When I first tried 3-point tracking, I found it frustrating that my legs didn’t move. I was using HTC Vive at the time, and while my head and hands tracked perfectly, the lack of leg movement killed the immersion. I tried to get Vive trackers but couldn’t, so I decided to make my own. That’s how this all started.
Speaking of which, Hiro, you often mention the ‘Hiro Move’ in your blog. How did that pose come about?
Q: The story behind the ‘Hiro Move’
(Hiro): I originally used multiple cameras to test the reproducibility of movements with full-body tracking devices. I found that movements where joints come into contact tend to trigger tracking errors.
This pose helps identify where the tracking issues are most likely to occur, particularly with the hips. I’ve tried other IMU systems, and this move really highlights the differences.
(Yuki): I see! As a developer, it’s a challenging move to perfect. We’ll definitely work on creating a device that can handle the Hiro Move without any issues (laughs).
Q: How should Uni-motion evolve?
(Hiro): Other full-body tracking developers are pretty visible, so it’s easy to get a sense of their work. Uni-motion, on the other hand, is relatively low-key. It would be great if you could showcase your product more through exhibitions and try-on events. Interacting with users who are unfamiliar with Uni-motion will help it grow.
(Yuki): Thank you. We’re realizing that relying solely on our current community for sales has its limits, so increasing opportunities for people to experience the product is something we’re looking to pursue.
Q: What features should Uni-motion have?
(Hiro): From a user’s perspective, it’s not so much about the technology behind the device but about the experiences it enables. If Uni-motion can continue to offer a user-friendly, hassle-free experience, especially for beginners, that would be fantastic. Engaging with people who are completely new to full-body tracking is key to achieving that.
Q: Current challenges
(Hiro): The main challenges with full-body tracking are the setup, charging, and calibration. With Uni-motion, the need to recalibrate after changing the battery is an immediate issue.
(Yuki): “A full-body tracking experience that beginners won’t give up on”—that’s a great concept. It’s come up a few times today, and it’s something our team will definitely focus on. We’ll do our best to streamline the process as much as possible. Regarding the battery issue, it’s a hardware challenge, and we’re hoping to address it in future products.
Q: Thoughts on the future of the VR industry
(Hiro): I’ve noticed a significant increase in interest not just in full-body tracking but in other types of tracking as well. The lack of facial tracking in VR while wearing a headset is a major issue. Most users have powerful graphics cards and want to jump into full-body tracking right away.
I believe the demand for facial and eye tracking will only grow, and I’m eagerly awaiting more devices that can meet these needs.
(Yuki): The recent surge in interest is likely influenced by streamers like Stanmi. Their content has been trending on YouTube, and the industry is getting more attention than ever before.
Facial and eye tracking are crucial. Whether or not we can develop these features remains to be seen, but we’re committed to ensuring Uni-motion works seamlessly with other devices.
Q: What would be the ideal VR experience?
(Hiro): The ultimate goal is to replicate real-world movements as accurately as possible. I hope VR and full-body tracking can contribute to a safer and more convenient society. Many people lose their lives in workplace accidents, traffic incidents, and so on.
Full-body tracking allows for precise reproduction of human movements, enabling low-cost, quick simulations and drills in VR. This can ultimately enhance safety and efficiency in society.
I encourage everyone to try VR and full-body tracking and discover just one thing that makes them say, “I can do this in VR!”
(Yuki): Achieving more accurate real-world tracking ties into the concept for our next product. We aim to offer both accuracy and affordability.
Aside from full-body tracking, I’m personally involved in mechanical projects as well. I hope to create something that combines VR and machinery to benefit society.
New Information & Announcements
- The Official Uni-motion Booth Shop is Now Open!
To celebrate the launch, we’re offering a free download of our official character, Unimo-chan. Be sure to download it and have fun using the Unimo-chan avatar in VR!
Visit our official Booth shop here!
Don’t forget to share your photos using the hashtag! #TodaysUnimochan
- Uni-motion Update Announcement
From this month through the end of the year, Uni-motion will be rolling out various updates. These will include improvements to tracking accuracy and calibration, UI enhancements, and new settings to make your Uni-motion experience even smoother.
The first update is scheduled for early September.
Update details:
- “Debugging tools added to Uni-studio”
- “Clipboard copy function for Uni-sensor information”
With more members joining our development team, we expect to release updates more frequently. Stay tuned and get excited for what’s coming!
Once again, thank you to everyone who attended. The date for the next event is still undecided, but we’ll continue to create spaces for communication with our users.
For the latest updates on our products and events, be sure to follow Uni-motion on X (formerly Twitter). We appreciate your support and look forward to seeing you again soon.
Thank you for your continued support of Uni-motion.