Haptics in cars Juha Hjelm

University of Tampere Department of Computer Sciences Seminar “Haptic Communication and Interaction in Mobile Contexts” Fall 2008

Contents 1.Introduction....................................................................................................................1 2.Safety..............................................................................................................................1 3.Haptic devices.................................................................................................................2 3.1.Haptic steering wheel............................................................................................2 3.2.A pneumatic tactile alerting system for the driving environment...........................2 3.3.Haptic gas pedal....................................................................................................3 3.4.Nissan haptic gas pedal.........................................................................................4 3.5.Haptic car seat......................................................................................................4 3.6.Maplin massaging car seat....................................................................................4 3.7.Universal haptic control........................................................................................5 3.8.Immersion TouchSense PR-1000..........................................................................5 3.9.BMW iDrive.........................................................................................................6 4.Acceptance......................................................................................................................7 5.Summary........................................................................................................................8 References ........................................................................................................................9

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1. Introduction The driving environment can have a lot of distractions for the driver. Other cars, traffic lights, other passengers and phones can all distract the driver from focusing on driving. The most commonly used senses while driving, sight and hearing, can become overloaded. Critical messages have a better chance of reaching the driver, if you use another kind of stimuli, such as haptic feedback. In the past few years there has been researched and developed many haptic devices that can help the driver to focus on driving and that way increase safety and make driving more comfortable. You can use haptic feedback on several different parts of the car. In this paper the haptic devices have been divided to two groups, depending where they are located: haptic devices that are constantly in contact with the driver, and those that the driver must actively touch to feel the haptic feedback. The devices that are constantly in contact with the driver are located in the seat, the steering wheel or in the pedals. The other haptic devices can be anywhere in the car, but most commonly in the various buttons, knobs and levers. The safety issues are one of the critical issues when designing cars. There are basically two ways why haptic devices can increase safety. Haptic devices can be used actively by giving warnings to the driver or for example, by applying pressure upwards from gas pedal, in case of speeding. The other way is to make the devices the driver uses haptic. This way driver can concentrate on driving and use his sense of touch to operate the devices.

2. Safety It is often assumed, by the manufacturers, that adding more functionality to vehicles increases user satisfaction or pleasure. This maybe true, but adding too much functions and technology to the cars may start to distract the drivers and cause accidents. Studies have shown that cellular phones, navigation systems, voice e-mail systems can distract drivers significantly [6]. The driver’s attention is in many situations divided between many different things. The driver might be talking on the phone or using the navigator or a radio, while trying to drive safely. When the driver uses many of these devices he has to take his eyes off the road and often one or both of your hands off the steering wheel. Even simple voice-based systems can distract the driver. Part of the problem is that consumers demand for new features even though they might be a safety hazard [7]. It is clear that while driving the driver’s typical audio and visual methods of interface between the car and driver are already saturated. Haptic cues might offer a promising and relatively unexplored alternative to auditory warnings and other messages, which could speed response and reduce annoyance especially in event-driven and information-rich situations. [6]

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3. Haptic devices The haptic messages can come from different sources in the car. In this paper four different locations are studied: steering wheel, gas pedal, car seat and universal control. The first three are, more or less, in continuous contact with the driver, but the universal control is a device that must be deliberately touched by the driver to feel the haptic feedback. The first three give haptic feedback generally by vibrating. The vibration can be differenced by varying the frequency or location. They are also good at giving warnings to the driver, because they always are in contact with the driver. The universal control is different from other devices that it is not generally used to give warnings to the driver and that it allows also users input. The other devices generally give one-sided signals, but with the universal control the user can also influence the system with his actions.

3.1. Haptic steering wheel The steering wheel has certain advantages to have haptic feedback. The driver has continuous contact with the steering wheel and ideally has both hands on the wheel. This means that the steering wheel could be used to give directional information from a GPSnavigator. Also because the hands are quite sensitive to touch, you can give the driver varying signals and the driver can sense the difference. But still the biggest use for haptic feedback from the steering wheel is to alert the driver of driving hazards or for example of low fuel levels. The steering wheel also has disadvantages for haptic feedback. The driver might not have both hands on the wheel or that the driver might only have a light touch on the wheel, this might often be the case on longer trips. In these cases directional information or all information might be missed.

3.2. A pneumatic tactile alerting system for the driving environment Enriquez et al [1] have developed a steering wheel that uses a pneumatic pump to produce pulsations in different frequencies and in different places on the wheel. The steering wheel has inflatable pads that could be inflated and deflated rapidly, to convey information to the driver. The system could potentially be used to give directional information to the driver, but the main purpose for the project is to alert the driver of possible problems. The system was tested with multitasking tests and the test subjects reaction times were measured with different stimuli. For the tests a "mock" steering wheel was provided, but the tests were conducted inside with a computer and the steering wheel.

3 From the tests they found that tactile feedback from the steering wheel lowered reaction times and also that different frequencies of the vibration can provide extra information to the driver. With the system, stimulus could be localized to a specific area on the steering wheel. Because of this you can have multiple stimuli on the wheel, but it can also cause problems if the driver isn't driving with both hands on the wheel.

3.3. Haptic gas pedal The gas pedal may be used to provide haptic signals for the driver. The signals have been designed to warn the driver about the distance to the car ahead, low fuel levels or when is the optimum time to change gears. The most interesting ways to use haptic gas pedals though is to use it to keep driver from going too fast by pushing the gas pedal up. You could use it to prevent the driver from speeding or slowing the car down because of other traffic. The problem is that it might be difficult to convince the drivers to use a system that might take away some of the control of the car. Also in some situations this kind of system might become dangerous, if the car would slow down in the freeway, because of sensor malfunction. The gas pedal is also not the optimum place to give haptic feedback, because the feet are not as sensitive to touch as for example hands. The feedback given in the pedals is potentially more limited than can be given in other locations. Cruise control, that many cars have, also potentially can cause problems. Many newer cars already have cruise control, so drivers can drive their cars in many situations so that they don’t have to touch the pedals at all. In these situations the haptic feedback has to be given in another manner.

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3.4. Nissan haptic gas pedal Haptic gas pedal was researched by Nissan in 2002 [2] to explore the possibilities of developing a support system for drivers for car-following. Sensors would monitor the distance for the car driving ahead and if the distance would fall to potentially dangerous; the gas pedal would push upwards so that the car would lose speed. The driver would not only see the separation between cars change, but would also feel it. This would allow the distance between the cars to remain constant. The information gained from prototype tests proved that the drivers did give way to the force from the gas pedal. Also they found that haptic feedback was good enough to replace the visual feedback temporarily.

3.5. Haptic car seat A car seat can be also used to give the driver haptic messages. It shares most of the advantages that the steering wheel and the gas pedal has. Unlike the steering wheel and the gas pedal it is something that is guaranteed to be in contact with the driver continuously. This makes it an ideal place to warn the driver of potential threats. The seat can also differentiate the messages by having them on different places. You can place the messages on the lower or the upper parts or on the left or the right. Although it must be remembered that the back isn’t the best place to give subtle messages, so the messages given must be strong enough to be clear. If used fairly rarely the messages will certainly get the drivers attention.

3.6. Maplin massaging car seat Maplin [8] has an inexpensive heated massaging seat that is places on top of the normal car seat. The seat has several massage programs and can isolate the massaging vibration to a specific location. The massaging seat is not really a haptic device, but the device shows how easy it would be to make a haptic car seat. You would only have to make it give meaningful messages, such as from a navigator or warning messages.

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3.7. Universal haptic control Various controls in cars can have haptic properties, so that a single control can be used for controlling several different things. Force-feedback control can emulate the feel of many different conventional controls. The control can have detents, limits stops and friction, but can also have new effects, like vibration, scrolling and free spin. With a single haptic control, the driver can access all the cars functions from a single place. The knob acts different according to what function the driver is trying to use. When all the cars functions can be controlled with one haptic control, the driver doesn't have to search for the right button or look at the control when using it. This adds to safety of driving, because the driver can keep his eyes on the road and it can also be faster to use different controls. But because of the limitations of sense of touch, there also has to be another medium of conveying information to the driver. Sound or vision has to be used to inform the driver on what function is being currently used.

3.8. Immersion TouchSense PR-1000 The Immersions device [5] can be used to make a universal control. It can produce the “feel” of several different controls.

Barrier. Sensation of hitting a hard stop. Barrier effects restrict the user’s motion and are useful for indicating first and last items, minimum and maximum, or the edge of an area.

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Compound. Two or more effects such as barriers and detents. A compound effect, like small detents with a deeper center detent and barriers on both sides, would be appropriate for a balance control, for example. Compound effects help designers closely match tactile sensations to operational steps, which can enhance usability.

Constant Force. Continuous force independent of position. Constant force can be used to simulate dynamics such as gravity, friction, or momentum.

Detent. Notches associated with selection position. Used to mark fine or coarse increments or selections, detents can be customized in size, shape, and number to suit context-sensitive requirements.

Hill. A plateau style of wide detent. A hill effect could be used for menu wraparound, letting the user know they have moved from last to first menu item. A hill can also be used to indicate a return from a submenu back to the main menu or to signal the crossing of a boundary. 3.9. BMW iDrive The BMW iDrive [3] controller is situated in the central panel of many of the newer BMW-models. With the controller the driver or the front seat passenger can control many functions, all from one place. This includes information from the on-board computer, the settings for the sound system or directions given by the navigation system. The information is shown on the control display as the information is cycled through with the controller. The information can also be projected to the windscreen so that the driver can keep his

7 eyes on the road. The controller gives haptic feedback so that the driver can focus on driving. The haptic controller is made with Immersion TouchSense. Unfortunately the iDrive hasn’t garnered very glowing reviews. The system idea is great but the realization didn’t work as well. Jakob Nielsen [4] writes about the biggest problems, which include: • Slow response times •

Clumsy task flows.

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Misleading mapping

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Obscure abbreviations.

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Lack of situational awareness.

4. Acceptance It might be difficult to get user acceptance for haptic interfaces. As with all new devices, use of haptic interfaces can lead to frustration if the function doesn’t work as the user wants or expects it to work. So you must use caution when designing haptic interfaces, especially when designing the first commercial systems. This was especially notable with the BMW’s iDrive system. [4?] The system was non-intuitive and didn’t work as well as advertised. Drivers are not used to getting haptic feedback and it could be seen as annoying, so it might be a good idea if the users could determine themselves the level of haptic feedback they want. Haptic cues can also be seen as intrusive, as all messages are conveyed immediately and most people do not have natural reactions to vibratory cues. Drivers, who are not aware how dangerous their current driving style is, could also react negatively to the vehicle showing them a safer driving style. Special care must be taken when designing a haptic warning system. The chosen warning (haptic, visual, audio) must suit the situation. If the warning is not properly designed the driver might respond to the situation incorrectly, such as ignoring it and

8 causing a dangerous situation. An inappropriate response to a warning could be as bad as no warning at all. Thus the warning system should promote appropriate reaction. It should also be noted that sometimes haptic messages can also divert the driver’s attention from where it is actually needed. [1] [6] [7] Two things affect whether the users are willing to accept a warning system. 1. How disturbing the warnings are 2. How common false or trivial warnings are Frequent disturbing warnings will decrease driver acceptance and trust to the system. Ultimately success of warning systems depends how well the interface suits the situation and to the driver’s capabilities.

5. Summary The driving environment can have a lot of distractions for the driver, so safety issues are the most important research area for haptic devices in cars. Haptic devices seem to be a natural way to inform the driver of hazards, because touching someone results in an immediate reaction. As a result most of the haptic devices researched are designed to increase safety while driving. In this paper the haptic devices are divided to two groups: devices that the driver has continuous contact with and devices that the driver must actively touch. The first group has the steering wheel, gas pedal and the seat. And the second group involves all the different buttons and levers. The devices in the first group are good at giving warnings to the driver, but the haptic controls allow the driver to concentrate on driving and use his sense of touch to operate the devices. Haptic devices have many advantages. They attract attention immediately, they use a sense not commonly used and they can give different messages by varying the location and the frequency. There are also some disadvantages. The user can become numb to the messages, the user has to learn what the messages mean and the messages can seem annoying to the user. The haptic devices described in this paper can have a major impact in increasing driver safety and comfort. Acceptance and gaining trust of the users for haptic systems might be a big issue, especially acceptance of haptic warning systems.

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References [1] Mario Enriquez, Oleg Afonin, Brent Yager, Karon Maclean, A Pneumatic Tactile Alerting System for the Driving Environment, 2001 [2] David A. Abbink, Neuromuscular Analysis of Haptic Feedback during Car Following, 2002 [3] BMW iDrive http://www.bmw.com/com/en/insights/technology/technology_guide/articles/idrive.h tml checked 15.12.2008 [4] Review on iDrive http://www.useit.com/alertbox/20040315.html checked 15.12.2008 [5] Haptic control knob http://www.mp3car.com/vbulletin/input-devices/95509new-product-force-feedback-haptic-encoder.html checked 15.12.2008 [6] John D. Lee, Joshua D. Hoffman and Elizabeth Hayes, Collision Warning Design to Mitigate Driver Distraction. Proceedings of the SIGCHI conference on

Human factors in computing systems. ACM Press, 2004, 65-72. [7] Steve J. Summerskill, J. Mark Porter and Gary E. Burnett, Feeling your way home: The use of haptic interfaces within cars to make safety pleasurable. 3rd

International conference on 'Design and Emotion'. 2004. [8] Massaging car seat http://www.maplin.co.uk/Module.aspx?ModuleNo=98894&source=1