In addition to the handle, what other VR input devices do you know? (Part 1)

Regardless of whether 2016 is the first year or not, we can feel that VR is growing vigorously through the development of 2015. In this year, we have seen an endless stream of helmets, the most typical and the most talked about are the helmets of the three VR giants: Oculus Rift, HTC Vive and PlayStation VR. At the same time, the market also has input devices that echo the helmets.

An input device is a device that can map the environmental data of the real world to the virtual world. Roughly speaking, it is a device that inputs people's commands into the VR system. Unlike keyboards and mice, VR input devices emphasize immersion. Therefore, with the development of VR headsets, VR input devices are also ushering in spring. It not only has a wide variety of novel forms, but also covers fantastic ideas and black technologies.

In fact, in addition to traditional controllers, such as the Xbox wireless controller supported by the Oculus Rift consumer version, there are also some emerging input devices, such as the universal treadmill Kat Walk, gloves The Manus or clothes Tesla Suit. Below, let the reporter take you to take stock of the representative products in the field of VR input devices. But before that, let's make a simple classification.

Although there are many ways to classify products, such as gloves, handles, double handles, and full-body suits based on product form, or sensory immersion and interactive immersion based on immersion, the reporter believes that classifying products based on the technology they use is more helpful for people to understand the product.

The first type is the traditional handle

Using inertial sensors and vibration motors, this type of input device is generally operated using traditional buttons/joysticks/touchpads and interacts through vibration. The most typical ones in the industry are:

The default Xbox wireless controller for the Oculus Rift consumer version

PS4 with PlayStation VR (PlayStation Camera is also required)

In addition, there are VR controllers launched by other manufacturers, such as the domestic Ximmerse team. However, the above two models are already very representative, so I will not go into details.

The second type is the motion sensing handle

Before we begin, there is one thing we need to say. Generally speaking, inertial sensors are composed of accelerometers (for measuring acceleration), gyroscopes (for measuring angular velocity), and magnetometers (for measuring the direction of gravity). However, current consumer-grade inertial sensors have difficulty tracking six degrees of freedom. Generally, they can only track three degrees of freedom, namely the rotation of the X, Y, and Z axes, and cannot measure the translation of these three axes. To put it simply and roughly, if you hold a handle made of an inertial sensor and move it extremely slowly and uniformly in a horizontal position, the handle will be difficult to perceive.

However, people need to capture six degrees of freedom in a virtual environment to provide a better input experience. Therefore, motion sensing controllers generally provide six degrees of freedom motion tracking through an inertial sensing system plus an optical tracking system or magnetic field sensing.

Samsung's mysterious Rink

According to the news, Samsung will show its input device Rink for Gear VR at CES. We know very little about it at present, and can only explore it through the video released by Samsung (it looks very accurate...).

Through the video, we can see that Rink has gesture recognition and position tracking, and different fingers can trigger different interaction methods. It is certain that Rink uses inertial sensors, but if you want to get more specific technical principles, you may have to wait until the CES exhibition.

Industry benchmark Oculus Touch

Basically, the technical framework of Touch is multi-modal sensor fusion + gesture recognition. That is, it is equipped with inertial sensors and Oculus's motion tracking system Constellation for optical tracking to achieve Touch's 6-degree-of-freedom tracking. It is worth mentioning that a tracking camera is also needed for motion capture. However, according to the latest news, the Touch, which was originally scheduled to be shipped in the second quarter, has been postponed to the second half of this year. Therefore, more specific and detailed technologies may need to wait until then to understand. However, it is worth waiting, after all, Oculus has created a benchmark for the industry.

HTC Vive's footprint tracking system

The HTC Vive's handle achieves motion capture through its own tracking system Lighthouse. Its principle is to use the extremely dense invisible light in the room to detect the position and movement changes of players wearing VR devices in the room, and simulate them in 3D space. Specifically, Lighthouse is a spatial tracking system based on 15×15 feet. Two laser emitters will be placed at opposite corners of this space, and will continuously emit light to scan the entire space. There are more than 70 photosensitive sensors on the Vive helmet and handle. As the laser scans, the helmet and handle begin to count like a stopwatch to see which sensor receives the laser first, and then use the relationship between the sensor position and the time to receive the laser to calculate the exact position relative to the laser emitter. As long as the laser beam hits enough photosensitive sensors, a 3D model can be formed. However, this seems to be information about the developer version of the handle.

According to the latest news, the consumer version of the HTC Vive controller has been greatly improved. But the specific technical details are not yet known, and we can only wait until the CES exhibition. (Look, there is a camera in the center of the helmet.)

PS VR's old-school PS Move controller

The PS Move controller was launched on September 15, 2010, and is a product of the PS 3 era. However, Yoshida Shuhei once said that Sony will not upgrade it for PS VR. In an interview, Yoshida Shuhei said: "We think the current (PS Move) is good... Move was originally developed for use in VR games. But when it was launched, both the PS4 and PS VR were still trade secrets, so its original features were not fully introduced at the time." The Move controller has a built-in inertial sensor, uses a camera for tracking, and uses RGBLED light source bulbs as active markers.

Razer Hydra vs Sixense STEM

Before getting down to business, the reporter wants to emphasize the Chinese name of Razer Hydra - Nine-headed Spirit Snake (is this name cool?). This is not a new product, just like PS Move, it is an antique. Although VR is not the original intention of Razer Hydra, many people use it as a VR interactive device, such as Philip Rosedale, CEO of Linden Labs (which operates the well-known game "Second Life"). At last year's SEA-VR conference, Rosedale demonstrated the latest VR game "Virtual Toy Room" to people through Hydra (as shown above).

Razer released Hydra (pictured above) in April 2011, priced at $139. In fact, Hydra is a set that includes a spherical base station and a pair of wired handles, and the left and right handles each provide traditional controls such as analog joysticks, four buttons, and trigger buttons. Specifically, the spherical base station emits a weak magnetic field and uses it to sense the distance and direction of the controller. At the time, Razer boasted that Hydra can accurately identify a movement distance of 1mm and a rotation angle of 1 degree. Coincidentally, Sixense's STEM controller set, which was launched on crowdfunding in September 2013, also uses this magnetic induction tracking technology.

As shown in the picture above, the set includes two handles, three wearable trackers and a base station. Those wearable trackers can be worn on the head/waist/foot for full-body motion sensing, and the base station supports up to 5 tracking objects. More importantly, STEM is made for VR. The last gossip is that the technology of Razer Hydra came from Sixense. However, the amazing STEM was delayed for more than a year, and now the interactive devices of the three major helmets have been released, it is estimated that STEM will not have much role to play...

In addition to the above local motion tracking, there are also interactive devices for full-body motion capture. Please pay attention to the next part of this article for details.