More details have emerged on Valve's upcoming Knuckles controller for SteamVR. Having now graduated from prototype status, Valve has begun shipping Knuckle's dev kits to developers to test and design new functionality around the controller's capabilities.
Valve also posted setup instructions that detail the new controllers, including how to grip them. Similar to HTC's motion controller for its Vive headset, the Knuckles controller taps into Steam's Lighthouse tracking system for 3D positioning.
Valve says the controller has to first be paired with a Vive headset before downloading a driver. The company also notes that its controllers are only supported in the SteamVR beta branch at this time. Opting in is easy—just open your Steam client and find SteamVR under LIbrary > Tools, then right-click SteamVR, select Properties, and select "beta" from the drop-down menu.
You can see in the diagram above that there are two face buttons next to the trackpad, along with a system button just below. The controller is designed to clamp onto the backside of your hand. In theory, this should make it easier to let go of the controller to virtually grab and pick up objects in VR.
Being able to let go of the controller is a big advantage over existing motion controllers for the Vive and Rift. It allows for a more immersive experience, one in which you should be able to open your hand to grab a ball and throw it in a more natural manner.
For this to work well, users will need to first calibrate the three capacitive sensors that are used to track your middle, ring, and pinky fingers. Otherwise, finger tracking will be "very poor" in an uncalibrated state, Valve says. However, this is a temporary measure for dev kits; the finalized hardware shouldn't need any calibrating.
In addition to picking up objects more naturally, Knuckles opens the door to gestures. Imagine flipping a bad guy the bird, or using two fingers to point to your eyeballs to let someone know you're watching them, as Robert De Niro does in Meet the Parents, and, we assume, in everyday life. Or using a finger to draw a map on a sandy beach as you lead a group into battle. There is a wealth of opportunity here.
Valve has not said when we might expect to see a consumer version of its Knuckles controller, though according to Tom's Hardware, it did previously announce it was working on three games that will take advantage of finger tracking this year.