Osaka-Kansai Expo Technical Article - Vibrating Stones Guide Expo Visitors & The Future of Murata as Seen Through the 3DHaptics Technology of MIRAISENS

The echorb Wonder Stone elicits cries of amazement and wonder through vibration-based resonance experiences

One day back in May, cries of surprise were heard from visitors to the Better Co-Being signature pavilion sponsored by gold partner Murata as they interacted with echorb Wonder Stones, devices packed with cutting-edge technologies from Murata.
The echorb is a device that uses special vibrations to create the illusion of pulled in users' brains. When visitors hold the echorb with its distinctive soft curves, its vibrations make them feel like their arm is being pulled forwards and backwards and left to right. Moreover, when visitors stand in front of the art exhibits in the pavilion, the echorb vibrates in sync with the artwork to create resonance experiences in various locations throughout the pavilion.

The technology incorporated in these echorb Wonder Stones is called "3DHaptics." Murata also uses millimeter wave radar sensors and load sensors for measuring visitors' heartbeats, as well as LF antennas to detect the position of the echorbs inside the pavilion.
In this technical article, we will first focus on the 3DHaptics technology and then introduce MIRAISENS, the Murata Group company working on this technology, ending with an exploration of the future potential of haptic technology.

The above graphic lists the technologies incorporated into the echorb Wonder Stones. The LF antenna and actuator are manufactured by Murata. The echorb Wonder Stones are equipped with many custom electronic components.

Meet MIRAISENS, the company behind the 3DHaptics technology that uses vibrations to create illusions within the brain

According to MIRAISENS co-founder Natsuo Koda, "3DHaptics is a technology that significantly expands human senses and breaks new ground."

MIRAISENS was founded in 2014 as the first start-up company by the National Institute of Advanced Industrial Science and Technology (AIST). The idea behind the company came when Koda, who had retired from Sony-Kihara Research Center, met Dr. Norio Nakamura, who was researching 3DHaptics technology at AIST.
The key feature of this 3DHaptics technology is the ability to reproduce the force sensation of being pulled, the pressure sensation of hardness and softness, and the tactile sensation linked to the sense of touching something. Recognizing the massive potential behind this technology, Koda founded MIRAISENS together with Dr. Nakamura.

How can this technology reproduce various tactile and force sensations? The key word for explaining this phenomenon is "illusion." Koda explains, "For example, in the case of an optical illusion, a line that is actually straight appears to be curved. In other words, illusions harness the brain's power to make someone experience something impossible."
He further emphasizes, "The MIRAISENS technology is very special in that it uses vibrations to create an illusion in the brain. Using this technology allows us to remove inherent physical limitations and generate new experiences."

For example, a typical game controller emits minute vibrations to convey the road conditions experienced by a car in a racing game. However, the MIRAISENS technology provides a more realistic experience by using vibrations to reproduce a wider range of sensory expressions, such as the sensations of being pulled, resistance, and roughness.

In 2019, Murata announced that MIRAISENS would be joining the Murata Group. Looking back on the situation at that time, Koda recalls, "I knew that a vibration algorithm alone was not enough for MIRAISENS to take the next step."
He felt that the company needed to work on an actuator component capable of generating precise vibrations to properly create such sensory illusions. So they decided to team up with Murata, a comprehensive manufacturer of electronic components.

Joining forces with Murata helped MIRAISENS finally obtain the actuator it had long desired. Koda explains, "I was happy that Murata didn't dissolve MIRAISENS simply because we joined the Group. They adjusted their internal systems, etc. so that we could maintain the pace of a start-up company. We were able to combine the capital strengths of a major corporation with the speed of a start-up."

This sense of speed and technical expertise were applied to the development of the echorb Wonder Stones for the Osaka-Kansai Expo.

Developing a portable 3DHaptics device that previously did not exist in "six months instead of two to three years"

MIRAISENS was specifically chosen for this project in April 2023. During planning and discussions for the Better Co-Being signature pavilion exhibition Murata would sponsor at the Osaka-Kansai Expo, Murata landed on the idea of developing a stone-shaped device that incorporates 3DHaptics technology.
Previously, MIRAISENS had only worked on 3DHaptic devices that connected to a computer. A portable device that operated independently was unprecedented, and its path to development was unknown.

Kenji Kagayama from the MIRAISENS , who was in charge of the actuator that generates the vibrations at the core of the 3DHaptics technology, recalls, "We completed work that would typically take two to three years in about six months. Murata has always worked with actuators, and I think that we were able to pull this off thanks to Murata's expertise as a comprehensive electronic components manufacturer and the overall competence of everyone involved, including the people at MIRAISENS."

The team developed a unique actuator that can output vibrations in two directions.
Typical actuators can only output along one axis, or in other words, in one direction. However, this actuator is capable of output along two axes.
This allows the actuator to achieve the complex illusions of users being pulled forwards and backwards, left and right, or in any direction, while also providing the exceptionally accurate vibration strength and responsiveness needed for tactile and force sensations.

However, the actuator alone could not create an illusion in a large number of visitors. Software control technologies and innovations on the hardware side for the echorb's design were also required to maximize the effect of the actuator.

According to Keito Kito, who was in charge of the software development , when Expo staff tried the echorb in March 2024, roughly a year before the opening of the Osaka-Kansai Expo, "The sensation was weak, and they didn't really feel like they were being pulled." To address the problem of how people would perceive the vibrations, they eventually invited people who had never experienced 3DHaptics technology once or twice a month to conduct repeated testing based on the belief that "at least we have a valid algorithm for creating illusions."

The team tackled hardware issues with ingenuity as well. They optimized actuator placement while overcoming the challenge of making the stone lighter and slimmer to transmit vibrations more directly. For example, they attempted numerous trial and error approaches, such as drilling holes in the board. Hiroyuki Harada, who was in charge of the product design of the stones, explains, "Reducing the weight in one-gram increments eventually brought us to a workable point."

Supporting the echorb development through the power of imagination with the goal of bringing visitors joy

So how was the team able to overcome so many obstacles and deliver the echorb on time for the Osaka-Kansai Expo? According to Koda, "All of the team members were incredibly imaginative. Even though we didn't have detailed specifications for the stones, everyone kept imagining the smiles we would bring to visitor's faces."
He adds, "Previously, our work had focused on achieving a manufacturer's required specifications. However, no 'specifications' exist when it comes to thinking about a future society. We need to think independently about what society would be like in the future and immerse ourselves in a world with undetermined specifications."

Future fields of technological development are not fixed and will depend on the ideas

After witnessing the echorb in action and seeing visitors' responses at the Osaka-Kansai Expo, the MIRAISENS team members commented, "It reminded me how amazing 3DHaptics technology truly is," and "I was happy to learn that everyone can enjoy this technology."

Potential applications of 3DHaptics technology include generating more realistic experiences with game controllers and providing directions to the visually impaired by incorporating it into their canes.
However, Koda excitedly explains, "Based on our experiences at the Osaka-Kansai Expo, we want to think about broader applications. We humans are typically unaware of tactile sensations, but we experience them intimately all the time. We want to take our current momentum and use this rush of ideas to tackle new challenges in new, previously unconsidered areas."

We will keep a close eye on future developments as MIRAISENSE leverages the Osaka-Kansai Expo to expand their efforts to new initiatives.