hey, this is me, rob, and this is the PIVOT device that I’m presenting you now
in this short video you see how PIVOT enables grasping virtual objects anywhere in space
but first, let me tell about how we came to the idea of this device
in VR there are two very different approaches for providing haptic feedback
one, is using haptic VR controllers – their main advantage is that they move with the user’s hand, not limiting their operation space
on the other hand, there are encounter-type haptic devices that are rendering natural touch and grasp to virtual objects
while also leaving user’s hand free when needed
their only downside is that they are often limiting the the motion space
with PIVOT we tried to combine the benefits of these two approaches: it provides haptics anywhere in space, just like handheld controllers,
while still allowing for natural free hand interactions, like with haptic proxies
let me briefly explain how PIVOT works
the device is mounted to the user’s forearm with a flexible cuff
It has a generically shaped haptic handle, that is pivoting around a motorized hinge
this simple design enables three key features
first, rendering grasp to handheld objects
second, catching and throwing fast moving objects
and rendering dynamic forces, such as inertia or springiness
the most straightforward functionality is grasping virtual objects
as you see here
as the distance between the virtual hand and the apple is shrinking, the handle pivots into the palm
at the moment when the user grabs the handle, PIVOT sends the signal to the virtual hand to also close the fingers and grab the apple
this way, PIVOT also serves as an input device for touch sensing
next, catching and throwing requires essentially the same mechanics as grasping
however, the action time to catch a flying object is orders of magnitude shorter
to overcome the natural physical limitations to make the mechanism extremely fast, PIVOT continuously checks if an object is flying towards the hand
and, if one enters the activation radius, the handle starts to move already in advance
accounting for the latency, and approximating the right moment of the collision
here you see my humble attempt to juggle with two apples
(I have to admit, I did cheat and reduced gravity)
the third key functionality of PIVOT is to render dynamic forces
as the branch bends down while plucking the apple, PIVOT drives its motor in the direction of the force,
effectively pulling the handle outwards of the user’s hand
while PIVOT has only one actuated joint, the rendered force is always a projected onto this axis
at the end, when the apple plucks, the motor stops pulling,
and additionally, there is a build in voice coil actuator in the handle that plays a “thud” vibration
this force rendering capability can be then applied to any types of forces, for example holding a wiggling bunny
or enabling bimanual interactions by coupling the two hands via synchronized push-pull forces
to evaluate these three key features of PIVOT we’ve conducted a user study with three specific tasks
first, participants rated the realism of grasping objects with different shapes and sizes
second, they evaluated catching and throwing balls with different velocity and from different directions
and lastly, they sorted three billiard balls by their weight
for more details about the results, please refer to the paper
finally, I would like to show a couple of details about the hardware
what you haven’t seen yet, is that apart from the motorized hinge,
the device also has a passive radioulnar hinge, enabling more agency over the held object
additionally, the handle also featured a push button, that enables PIVOT to act as an on-demand controller
....or as a torch in a VR scene
with this I’d like to conclude my talk and thank to all my co-authors for this fantastic collaboration,
and for the opportunity at Microsoft Research to do this exciting project
and thank you for listening and happy to discuss more! bye-bye