Microsoft's research arm has developed what it claims is the world's first 3D touch-screen monitor with force feedback capabilities - allowing objects on the screen to offer different 'weights' and 'textures' to the user.
Microsoft's Actuated 3D Display with Haptic Feedback uses a robot arm at the rear to provide a resistive force against the user's touch.
Dubbed the Actuated 3D Display with Haptic Feedback, a name only a researcher could love, the project is the brainchild of Mike Sinclair, Michel Pahud and Hrvoje Benko of Microsoft's Natural Interaction Research Group. Demonstrated to the public as part of the company's TechFest 2013 event in Redmond, the system utilises the kinaesthetic haptic sense - the process of recognising objects through touch - to provide feedback a plain monitor simply cannot offer.
The system works by mounting the display - a commercial, off-the-shelf 3D monitor with multi-touch capabilities - onto a robot arm connected to the same computer. As the user pushes their finger against the screen to interact with the display, the robot arm pushes back - and can alter the strength of that feedback as required. One example used during the demonstration was an array of virtual blocks constructed from different materials: stone, wood and sponge. Each was designed to behave as realistically as possible in terms of weight and friction, with the robot arm making the user work harder to push the stone block backwards than the wood or sponge blocks.
'I had been interested in the notion of putting a robot behind something you could touch,
' claims Sinclair in a blog post
on the matter. 'Originally, I had wanted a robot arm with many degrees of freedom but complexity, costs, and safety issues narrowed down the options to one dimension of movement. At that point, I was sure that others must have already looked into this scenario, but after looking at the literature, it turned out no one had done this.
The system has uses beyond crude effort-based variant, however: the arm is capable of moving in fine enough degrees that a user can feel the 'surface' of a virtual object simply by dragging a finger over the top: the stone block feels smooth compared to the sponge block, for example. During one experiment, the team blindfolded testers and got them to brush their fingers over relatively simple shapes - including two-dimensional squares and triangles and three-dimensional pyramids, cylinders and wedges. 'There were even some subjects who were 100 per cent correct [in that test],
' recalls Pahud. 'That was definitely a surprise.
The team has already considered multiple usage scenarios for the technology, beyond a simple tech demo: Pahud has already created a volumetric medical imaging system that provides fine-grained control over magnetoresonance imaging (MRI) scans from a human brain - while the remainder of the team has considered more mainstream applications. 'There’s always 3-D gaming,
' Sinclair says, 'but also 3-D modelling, education, and medical. We anticipate improving the experience with crisper, more detailed feedback, such as texture.
The team's work isn't the first to consider the importance of haptic feedback to the touch-screen experience: several patents already exist in the field, many of which are in active use today - the on-screen keyboard of most tablets and smartphones provides a small vibration when a keypress is detected as a crude means of providing haptic feedback, for example. A more impressive variant of the technology is in the Tactus Tactile Layer, unveiled in Custom PC Issue 108, which causes physical 'bubbles' to appear on the screen when the on-screen keyboard is used.
Haptic feedback predates the smartphone and tablet boom, however. From the more prosaic Microsoft Sidewinder Force Feedback Joystick, which provided complex enough feedback to require a dedicated 16-bit Intel processor on-board and the Logitech Wingman Force Feedback Mouse to the frankly bizarre Novint Falcon
, engineers have been working to enhance immersion using the sense of touch for years.
Thus far, Microsoft has not indicated whether it plans to bring the Actuated 3D Display with Haptic Feedback to market as a commercial product.