inFORCE

Abstract

While previously proposed hardware on pin-based shape display has improved various technical aspects, there has been a clear limitation on the haptic quality of variable 'force' feedback. In this paper, we explore a novel haptic interaction design space with 'force' controlled shape display. Utilizing high performance linear actuators with current reading functionality, we built a 10 x 5 'force' shape display, named inFORCE, that can both detect and exert variable force on individual pins. By integrating closed-loop force control, our system can provide real-time variable haptic feedback in response to the way users press the pins. Our haptic interaction design space includes volumetric haptic feedback, material emulation, layer snapping, and friction. Our proposed interaction methods, for example, enables people to "press through" computationally rendered dynamic shapes to understand the internal structure of 3D volumetric information. We also demonstrate a material property capturing functionality. Our technical evaluation and user study assesses the hardware capability and haptic perception through interaction with inFORCE. We also discuss application spaces that 'force' shape display can be used for.

Embodied Axes: Tangible, Actuated Interaction for 3D Augmented Reality Data Spaces

“…Actuated interaction refers to feedback given through a tangible controller. For example, inFORCE [32] is a pin-based shape display that acts both as input and haptic display. The authors describe a series of use cases that include visualisation of geoscience data (earth layers), and a medical application rendering the pulse of a patient for medical training.…”

Button Simulation and Design via FDVV Models

“…Displacement has been approached in such a manner outside the button domain. One could cite as example applications the automotive gearshift [4], non-rigid materials [46,60], and human tissue [50]. Displacement-only models are relatively simple.…”

“…We believe this to be due to three engineering challenges: (1) modeling, (2) simulator construction, and (3) model-simulator separation. Firstly, prior work has modeled buttons' response as the displacement-dependent change in force [14,37,46]. However, as we show in this paper, an FD model is adequate only for linear buttons pressed at extremely low speed.…”

“…Secondly, the simulators created thus far have fallen short of the operation rate needed for a button press. General haptic devices such as Phantom [16,41,58] and inForce [46] operate at 60 Hz, while the skin's mechanoreceptors fire at about 1,000 Hz and respond to tiny changes in force [13,20]. Simplistic controller approaches may have further curbed attempts to render anything other than a linear button.…”

LiftTiles

“…Shape display is a promising approach to general-purpose shape-changing interfaces [1]. However, most of the existing pin-based shape displays focus on interactions at the scale of a human hand [4,3,5,6,7,8,10] because of the following three technical challenges when trying to create a larger-size shape display: 1) scalability: common electromechanical linear actuators are difficult to scale to larger sizes due to cost and fabrication complexity. 2) robustness: in a room-scale shape display, each actuator must support heavy objects like a human body, thus it must be robust compared to smaller actuators.…”