Characterization and Psychophysical Studies of an Air-Jet Lump Display

Abstract

Development of tactile displays to enhance palpation of lumps during robot-assisted minimally invasive surgery is challenging due to size and weight constraints, motivating a pneumatic actuation strategy. This work describes the quantitative and psychophysical assessment of an air-jet tactile display that creates a lump percept by directing pressurized air through an aperture onto the finger. The air pressure and aperture size are meant to control the hardness and size, respectively, of the perceived lump. Jet impingement pressure and flow rate were measured by capacitive tactile sensors and mass flow meters at varying aperture sizes and pressures. The air-jet pressure profile width evolves as jet theory predicts and is largely independent of supply pressure (and therefore jet exit velocity). The method of constant stimuli was used to determine the just noticeable differences (JNDs) for the air pressure and aperture size. Qualitative results indicate that subjects perceive the stimulus as a "lump-like" shape. Pressure JNDs ranged from 19.6-24.4 kPag and aperture size JNDs ranged from 0.50-0.66 mm. No significant correlation exists between the supply pressure and changes in perceived lump size. However, pressure JNDs show significant (p < 0.001) inverse correlation with aperture size, with improved discrimination at larger apertures, where a greater finger pad area is stimulated.

HAIR: HAptic feedback with a mobile AIR jet

“…The combination of three actuating axes enables the free interaction in a large working area but the resolution of the force is still limited. Finally, Bianchi et al [13] proposed to use the air jet for the direct tactile stimulation. It consists to direct a thin stream of air on the finger pad.…”

Mid-air tactile stimulation using laser-induced thermoelastic effects: The first study for indirect radiation

“…Such mid-air haptic displays have great potential for natural user interfaces (NUI). One prominent approach is to use air jets, e.g., a tabletop that emits air jets using an array of nozzles to the "air receiver" (a hollow cup) held in the user's hand for force feedback [1] and an air-jet lump display that varies air pressure and aperture size to render virtual lumps [2]. A possibility of rendering reliable tactile sensations using air jets at a longer distance (35 cm) was also explored [3].…”

Development of a puff- and suction-type pressure stimulator for human tactile studies

“…Currently, in the fields of brain and cognitive science (Allen & Humphreys, 2009;Dresel et al, 2008;Jousmaki, Nishitani, & Hari, 2007), neurophysiology (Golaszewski et al, 2002;Skedung et al, 2013), ergonomics (Auvray, Gallace, Hartcher-O'Brien, Tan, & Spence, 2008;Gallace et al 2007;Ho, Santangelo, & Spence, 2009), clinical skill acquisition, and surgery simulation (Bark et al, 2013;King et al, 2008;Philip et al, 2015), many studies have been conducted on the tactile sense. Because the necessity of providing an interface for tactile information in virtual or actual environments is increasing, various devices for delivering tactile stimulation have been developed (Gwilliam, Bianchi, Su, & Okamura, 2013;Monnai et al, 2014;Suzuki & Kobayashi, 2005). This is usually followed by electroencephalographic (EEG), functional magnetic resonance imaging (fMRI), or psychological studies to evaluate the performance and utility of each device (Ritter, Moosmann, & Villringer, 2009;Yuan et al, 2010).…”

“…This is usually followed by electroencephalographic (EEG), functional magnetic resonance imaging (fMRI), or psychological studies to evaluate the performance and utility of each device (Ritter, Moosmann, & Villringer, 2009;Yuan et al, 2010). Mechanical (Gallasch et al, 2010;Gwilliam et al, 2013;Wall & Brewster, 2006), electrical (Echenique & Graffigna, 2011;Kaczmarek et al, 2006;Yamamoto, Nagasawa, Yamamoto, & Higuchi, 2006), and thermal methods (Chouvardas, Miliou, & Hatalis, 2008;Kim et al, 2014;Yang, Wang, & Chen, 2015) for providing the three submodalities of tactile sensation (i.e., vibrotactile, pressure, and thermal) are being used.…”

“…Recently, a new method using an air-spray approach (also known as a pneumatic air jet) puff was developed to provide a pressure sensation. This technology is promising for utilization in a natural user interface (NUI), and is capable of providing stimulation without direct contact between the actuator and the skin (Gwilliam et al, 2013;Tsalamlal, Ouarti, & Ammi, 2013). Using the air-spray method, the weight of an object can be applied to the object's virtual footprint on the skin, or a virtual texture, shape, or compliance can be provided (Chouvardas et al, 2008;Gwilliam et al, 2013;Monnai et al, 2014;Suzuki & Kobayashi, 2005;Tsalamlal et al, 2013).…”