**5. Haptics in mobile gaming**

With the advent of smart phones, and other personal and portable devices such as MP3 players and tablets, which everyday include a richer set of sensory, processing, and memory capacities, videogames have finally make the jump from good old PCs and Consoles to the

Third generation of video game controllers included the Nintendo Entertainment System (NES) featured a brick-like design, Master System which has a similar design as NES and the Atari 7800. The fourth generation included Genesisi Mega Drive by Sega, TurboGrafx-16/PC-Engine and the Super Nintendo Entertainment System which had a more rounded dog-bone like design and added two more face buttons, "X" and "Y", arranging the four in a

In the Fifth Generation the Apple Bandai Pippin had a short live console designed by Apple Computer Inc. The Atari Jaguar was the first and last Atari console to employ the modern gamepad. Another example is the Neo Geo CD which was similar in shape and size to Sega Genesisi/Mega Drive game pads. Other examples include, The Sega Saturn, whose control pad introduced an analogue stick and analog triggers, Virtual Boy controller designed to use dual joypads, which was envisioned to control objects in a 3D environment. Sony developed a four direction D-pad, four actions were referred not by color or letter/number like most pads instead were colored shapes; triangle, circle, cross and square. The basic design and layout was based on that of Nintendo's SNES controller, as the PlayStation was originally developed as a CD add-on for the SNES, before becoming a console in its own right. It was the default pad for the first year of the PlayStation, until the release of the Dual Analog. It was often cloned for PC gamepads. The Nintendo 64 started to have both an analog stick and a D-pad. It has the

Originally designed for medical investigation, Physician Mark Ombrellaro developed a haptic vest that enabled the wearer to feel the impact of bullets, explosions and/or even hand taps in the trunk of the player's body. The 3RD Space Vest is commercialized by TN Games and is advertised as the only gaming peripheral device that allows you to feel what your game character feels. It works with pressured air to provide the player pressure and impact forces that can emulate a wide scope of direction and magnitude (TN Games, 2011). Others have worked on similar systems, and although they have not focused on the application in games specifically, it is clear how such technologies could also be applied in a game scenario. In the University of Ottawa in Canada, Jongeun Cha and others have worked in a device to enhance teleconferencing. They developed a jacket that enhances communication with the physical and emotional connection by allowing participants give encouraging pats to one another (Cha et al, 2009). Similarly, researchers at the National University of Singapore developed the Huggy Pajama wearable system, where the remote communication between parent and child is enabled through virtual hugs. This is possible by using a doll with embedded pressure sensors as input device and a haptic jacket as the actuator for the hug at the other end. The hug is reproduced by air pockets and the experience is further enhanced by adding a heating element to the device to mimic the

With the advent of smart phones, and other personal and portable devices such as MP3 players and tablets, which everyday include a richer set of sensory, processing, and memory capacities, videogames have finally make the jump from good old PCs and Consoles to the

traditional A,B,L and R buttons, along with a Z trigger button on its underside.

diamond formation.

**4.4 Haptic vests and jackets** 

warmth of a hug (Teh et al, 2008).

**5. Haptics in mobile gaming** 

mobile world. Smartphones and related devices are capable of rendering videogame graphics and sound in high definition, which aims at immersing the player in the game experience even with the limited size of the screen.

Because mobile video games are inherently restricted to small screens, game developers must rely on advanced user interface design to fulfill the input/output streams of media information necessary to play the game. Furthermore, most of the portable devices that serve as a platform for modern mobile games feature a touch screen as the main way of interaction with the device and its software interface. Most of the time such devices, either completely lack or, have very few physical buttons that the player can use to play the game. Even when physical buttons are present on the device, they are often located in places where using them as part of the game input controller makes it awkward for the player. In terms of haptic feedback, this is a limitation of such devices, since touch screens lack that physicality that players have grown used to with pc and other gaming consoles and their controllers.

To help with the lack of physical buttons and the sense of touch that they provide, mobile phones and devices are often capable of reproducing a vibration feeling. By controlling the moment, and duration of the vibration, to be synchronized with the touch of the screen, such mobile devices compensate the lack of hard buttons by giving a haptic feedback to the user whenever he/she presses a soft button on the touch screen. Although this is often good enough for common in-device tasks such as entering text on a virtual keyboard, from a gaming perspective the approach is very limited, as is the hardware available in most devices. Games require a higher degree of variation on the vibration to produce more rich and realistic experiences. Different levels of intensity, duration or even a specific vibration pattern must be applied for different events in the game play. The challenge in providing such degree of high definition on the haptic feedback is twofold. On one hand, hardware on the devices must be sufficiently advanced to permit the variation of intensity at which the internal motors will cause the vibration. And on the other the software must be sufficiently sophisticated to control the motors in such a way that a wide array of vibration effects can be rendered.

Research has been mostly focused in developing vibrotactile rendering techniques that can allow for a sophisticated touch feedback experience. Different algorithms have been tried to control the vibration motors and render the desired effects. Sang-Youn and others proposed a Traveling Vibrotactile Wave rendering technique which makes the effect of a traveliing sensation across the device display. It is based on controlling the vibrations of two motors, which permits to specify the location where the overlapping of two waves occurs. This control further allows the generation of a sensation of continuous flowing vibration by constantly changing the overlapping point, adjusting the timing of motor actuation. They tested their rendering technique with a ball rolling game (Sang-Youn, 2009). In another related work, they tested a miniaturized vibrotactile rendering system based on an eccentric vibration motor and a solenoid actuator, which generates vibrotactile information having a large bandwidth and amplitude. Their intention was to generate event-specific vibrotactile effects for a car racing game in a mobile device. The system could render human discernible effects for the events of collision, driving on a bump, and driving on a hard shoulder (Sang-Youn, 2006).

A good example on the latest advances in this direction is the MOTIV platform from Immersion. Their solution provides a TouchSense embedded controller technology to

The Role of Haptics in Games 229

A survey of strategies for making games accessible to the blind shows that audio is the most common used channel to either complement or substitute the visual channel (Yuan et al. 2010). AudioGames.net is an online community portal that has a repository of games whose interface is solely based on audio and the natural haptic interface of keyboard and mouse buttons (Audiogames, 2011). In terms of pure haptic games there are examples such as Haptic Sudoku for the blind, developed by Gutschmidt and others. In this technological solution they emulate visual perception completely by haptic perception. Players can feel the Sudoku board and scan the numbers by sense of touch using a haptic display, while audio cues alert the user of the outcome of their actions (Gutschmidt et al. 2010). Another example is Finger Dance, a sound based game for blind people. In FingerDance, user try to match musical rhythm patters to keystrokes in the keyboard. The game has no visual

The second approach is sensory substitution. In this case the cues that would normally come from the visual channel are replaced by haptic stimuli. This allows for the modification of currently existing games that were originally designed for non disabled individuals and

Blind Hero is a typical example of a game where sensory substitution has been applied to a very well known video game (Guitar Hero from Red Octane). Guitar Hero is a rhythm action game that is played by using a guitar shaped input device with colored buttons on it that must be pressed following the corresponding visual cues that appear on the screen at the peace of some rock tune. In the modified version, Yuan and Fomer replaced the visual cues with haptic stimuli coming from a haptic glove that has small pager motors that

VI-Tennis and VI-Bowling are another example of sensory substitution from their analogous version of the Wii Console (Wii Sports, 2011). In this case the haptic interface is based on a motion sensing controller enhanced with vibrotactile and audio cues that allows the players detect the key events in game play. In the case of VI-Tennis the controller would provide vibrotactile feedback to reflect the event of the ball bouncing and the timeframe at which the ball should be hit in return, while audio cues were left the same they ware on the original Wii Tennis game (Morelli et al., 2010a). For the VI-Bowling they implemented a technique called Tactile Dowsing where the Wii Remote is used to sense the direction to where the bowling ball should be thrown. With the Tactile Dowsing the player moves the remote left and right in a horizontal pattern. The receiver will detect the motion of the remote and the software prompts a vibrotactile feedback on the remote in a pulsing pattern. The delay between vibrotactile pulses is regulated so that the closer the player points to the optimal direction of the throw, the lower the delay and vice versa. This way the player can sense the direction the same way by trying to position the remote in a direction that has a near

In general, the term "Serious Games" refers to computer video games that are used with a purpose beyond or other than entertainment. However some discussion has been going on for some time about the formal definition and some other details about what may or may

feedback at all (Miller et al. 2007).

adapted to be played by the blind.

stimulate the tip of each finger (Yuan and Fomer, 2008).

continuous vibrotactile feedback (Morelli et al., 2010b).

**7. Haptics and serious games** 

not constitute a serious game.

enables a high degree of control over the vibration motors of the device. On the software side, they provide MOTIV Integrator for OEMs to include in their devices a vibration profile manager that leverages on TouchSense, and MOTIV Software Development Kit to enable developers to build third party applications and video games that also take advantage of the high definition vibration effects provided by their platform (Immersion, 2011).

Another approach has been taken by Senseg, a company based in Finland whose latest haptic rendering solution is a promise to revolutionize the way we perceive computer generated haptic feedback on touch screens and other real world surfaces. Their E-Sense Technology is based on biophysics; where instead of having the device's surface vibrate, they create a sensation of vibration directly in the finger's skin by using an ultra-low electrical current from an electrode to produce a small attractive force. The modulation of that force allows the production of any number of touch sensations that can range from vibrations, clicks, textured surfaces and more. A direct implementation of this technology is in the mobile device industry, and the provided software APIs would allow the development of video games with a sophisticated array of touch sensations (Senseg, 2011).

In terms of evaluation of the effectiveness of the haptic feedback on mobile gaming, Chui Yin Wong and peers tested the playability of a mobile game, using a vibrotactile feedback soft keypad, against playing the same game with a hard physical keypad. According to their findings, although players had higher scores using the soft keypad, they reported a preference on using the hard keypad in term of a better experience in the game play (Chui Yin Wong, 2010).
