1253, Københaven K
Haptics research engages with the questions of tactile perception and feedback. In recent years, haptics research has produced a couple of promising interfaces which are meant to bring closer digital information and the sense of touch [1, 2, 3]. This domain, however, is rather underdeveloped in terms of teaching due in large part to the fact that the devices that are used to create experimentations are either not publicly available nor affordable for students to get directly engaged with.
With the Motors & Music Platform, we (Daviid Gauthier, Bill Verplank and Jakob Bak) present teaching material focused on dynamic force feedback and sound synthesis for the learning of haptics. While toolkits for sketching and quickly prototyping haptics interfaces using vibro-tactile devices have been devised in the past , we are proposing to expand this initiative by introducing simple dynamic force feedback devices with high temporal resolution. Using simple and low-cost tool sets that we have developed specifically for engaging interaction designers with the study of haptics, our aim is to advance the quality of haptics research and experimentation in the classroom. Our approach is to provide students with specific and simple servomechanisms which feature high resolution sampling rates (position sensing) while offering high output refresh rates (torque control and sound).
In order to engage design students in the development of tangible experiences, we have devised and constructed a new Arduino-compatible board called “Motors&Music” (see figure 1) which together with dedicated software libraries comprise a platform for introducing concepts from haptics and sound synthesis in a hands-on educational context. The hardware platform has a motor controller (H-Bridge) and audio circuit (digital-to-analog converter and amplifier) which can be used to output control current/voltage and sound respectively. For the workshop two types of servomechanisms devices will be introduced.
The first is the Plank , repurposed voice-coil motors from old disk drives (see figure 3) which have been retrofitted with hall-effect sensors to provide position feedback information to the Motors&Music boards. The second is repurposed, motorized sliders from mixing consoles featuring a potentiometer to track slider positions. Combining these elements participants will be able to utilise the libraries to do embedded real-time integrated sound synthesis and dynamics control of the devices.
During the course, simple physical modelling techniques are be introduced in order to program first-order and second-order dynamics (position, velocity and acceleration) for both input (touch control) and output (force feedback) and produce perceptual phenomena such as springs, friction, damping, and oscillations. Mappings between the physical model of the haptic device and the on-board sound engine will focus on tone generation, pitch control, and frequency detuning.
 Bau, O., Poupyrev, I. 2012. REVEL: Tactile Feedback Technology for Augmented Reality.
ACM Trans. Graph. 31 4, Article 89 (July 2012), 11 pages.
 Bau, O., Poupyrev, I., Israr, A. and Harrison, C. 2010. TeslaTouch: electrovibration for touch surfaces. In Proc. of UIST’10, ACM, 283-292.
 Israr, A. and Poupyrev, I. 2011. “Tactile brush: Drawing on skin with a tactile grid display”. In Proc. of CHI’11, ACM, 2019-2028
 Moussette, C. “Designing Haptics” – Studio, TEI 2012.
 Verplank, B., Gurevich, M. and Mathews, M. 2002. “The PLANK: designing a simple haptic controller”. Proc. NIME ’02, ACM Press.