How to connect the virtual with the reality

"Avatar" in the Princess Beauty has not touched you, "Hobbit" Gollum (Gollum) to frighten you? How can these virtual characters have the power of being deeply rooted? Motion capture technology is a must. However, as a bridge between the virtual world and the real world, professional motion capture equipment is expensive, for ordinary consumers, especially for geeks, or both tall and not connected to the Earth, it is difficult to apply in their own products and ideas.

DEXTA Robotics Team of five young people, in the process of doing manipulator, found this blank, made a set of hand action capture Dexmo.

To get a clearer picture of their projects and products, let's take a look at a video.

This video is a collection of their early products, from which Dexta Robotics's hand motion capture technology has become smoother. They will also update the progress of the project in the near future.

Commercially available products for hand action capture gloves (data gloves) are used in several types of technology: IMU (inertia measuring unit) Inertial detection module scheme, Bending sensor class scheme, optical scheme. However, these types of technology are also inadequate: one is that these products are very expensive, it is difficult to achieve the consumer level, one is the need to add additional hardware to achieve force feedback.

Therefore, the DEXTA robotics uses the mechanical motion capture scheme, has done the hand the skeleton shape Dexmo, the hand bending movement through a group of connecting rod decomposition maps to the rotating sensor, calculates the position and the posture of the shot part, captures the hand movement.

Dexta Robotics's founder, Masan, told 36 Krypton that the approach was based mainly on three considerations:

First, mechanical action capture, high precision, can be measured in real time, and because it is to do the hand and other motion capture, so there is no difficulty in wearing problems.

Second, the external skeleton to add force feedback is easier, the other solutions are almost all gloves, from moving only the fabric of the glove surface, it is difficult to do not join other devices to do force feedback.

Third, under this scheme, DEXMO can be designed without expensive sensors, using a relatively low cost but relatively high accuracy of the rotating sensor. At the same time, the connecting rod and other mechanical parts can be produced by way of open mold, and the cost can be done very low under large quantity.

To ensure the accuracy and fluency of motion capture, hardware is only part of it, and algorithms and models are also important. The construction of hand model is one of the key points and difficulties. The software makes a relatively accurate hand model by analyzing the data to be read to the hand part. Dexta Robotics through the positive kinematics modeling of the external skeleton of the finger data, the inverse kinematics of the finger is analyzed by the calculated coordinate point. After many attempts, the team developed a relatively perfect hand model reconstruction program. Gu Xiao Chi also believes that the hand model reconstruction algorithm and software is also one of their major competitiveness. Currently, they have applied for three patents, including structure and algorithm, at home and abroad.

To achieve commercialization, the ease of use is also very important. Dexmo only need to wear the first time when wearing personal information (hand size) input calibration, after wearing can directly generate hand model, more convenient and quick.

The accuracy and cost of motion capture is very significant, for example, to do higher precision of DEXMO, we need to use higher cost sensors. And the valley Xiao Chi they want to do a set of low-cost, sophisticated algorithm and stable consumer action capture products, so the price and precision between the need for a balance. Gu Xiao Chi believes that the consumer level of hand action to capture the accuracy of the requirements may not be so high, research or sophisticated mechanical control may require relatively high precision, so their products in the framework of the structure of the situation in fact there will be high-end and low-end of the different configuration. High use of metal structure, high rigidity, small gap, while using non-contact angle sensor, the cost is relatively high but the service life is very long. Low matching is the use of injection molded parts to do the structure, relatively common angle sensor, can achieve consumer-level hand capture, the cost will be lower than the existing hand capture scheme.

About the price of Dexmo, Gu Xiao Chi said that this is not convenient to disclose, but will be lower than the existing prices of similar products. From my personal point of view, Noitom, like the Kickstarter, is now being raised, and the lowest payout price is at $200 trillion. Dexmo Future landing Kickstarter when the price of more than 200 dollars, competitiveness is likely to be affected.

(The above image is specially designed for the control manipulator of the space Positioning system, more suitable for robot control)

I think the DEXTA Robotics team's entrepreneurial experience is actually very interesting. However, they do not want to mention too much, Gu Xiao Chi said, "We are very serious in doing this company, hope to be able to do things first, others or later after the success of the project Kickstarter." We also understand that. So, for the time being, we'll just sort out some of the products and items we talked about.

36 Krypton: How is the product progressing now?

Gu: Our product is developed from last September, set up a team on March 16 this year, recently set up a company in the United States. Product research and development has been concentrated in the hardware itself, because the market has not previously had no external skeletal structure of the hand movement detection, so the hardware structure changes and iterations spent a relatively long time, are our team independent research and development. At present, the focus of product development has shifted to the software algorithm.

Hardware we are currently in sync to improve the micro-force feedback device development, and try to set its price more friendly, so that more people can experience the virtual reality and the fun of the robot. Recently, we put the products on the Kickstarter for small-scale trial production.

36 Krypton: What difficulties have you encountered in the course of this project?

Gu: The difficulty certainly has, will not be smooth sailing. Generally are technical problems, there are difficulties to solve it, after the settlement in fact also remember not very clear what. Remember how the force feedback on how to do more miniaturization has a relatively long period of exploration, mainly limited to the size of the brake and transmission mode. Drive aspects we have visited Dongguan veteran steering gear manufacturer Kpower, consulting about the feasibility and price of low-cost miniaturized Drive manufacturing, and how to find a balance between the two.

36 Krypton: Product and other supply chain management How's it going?

Gu: production, from the number of parts, Dexmo is indeed more complex, but Dexmo have a lot of duplicate parts, and the volume of parts are relatively small, you can put multiple parts into a mold production, so the problem in production is not too big. In fact, we have been very focused on production, and do not like to do scientific research, design a product, we must be able to produce. So we have consulted a number of mold manufacturers and mold design experience in the design of people, here to thank Seeedstudio and melt one of the engineers proposed, many times to modify the structure of parts, and finally Dexmo parts to do easy injection.

36 Krypton: How will Dexmo in the future be combined with VR?

Gu: We intend to participate in the Oculus Connect at the Oculus developer rally this September, contact the practitioners and developers of the VR industry in the United States, and also show Dexmo at the scene to collect some initial feedback. The VR industry is now growing faster in the United States, and in order to facilitate docking with other VR vendors and VR developers, we are also registering companies in the United States.

36 Krypton: How does the Dexmo and the domestic action capture team cooperate?

Valley: At present, our two partners, one is X-immerse, is to do optical hand space positioning and virtual reality operating system, as well as domestic imu action capture Authority Noitom. Concrete cooperation is still not good to disclose, anyway, simply said the goal is to allow more people to experience more mature low-cost robot control and virtual reality equipment. We also hope to be able to contact and cooperate with more people in the industry. Interested companies and individuals can send email to us, our mailbox is dexta@dextarobotics.com.