How Solenoid and Haptic Actuators are Transforming Automotive Safety Technologies

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Most cars are driven purely mechanically, however drive-by-wire technology is starting to make its way into the automotive sector. Many drivers are resistant to the change, especially with non-traditional controls such as a joystick; however, similar technology has been used in airplanes since the 1990s.

What is Drive-By-Wire?

Drive-by-wire uses electrical wires to control the car’s normal activities such as the throttle, braking, and steering. The upside of drive-by-wire systems is that they are lighter, have the potential to last longer (since moving parts cause most vehicle degradation), and significantly reduce the number of moving parts.

Drive-by-wire also involves the possibility of designing cars that could be controlled entirely with the hands (useful for many disabled drivers, who currently require expensive after-market mods added to their cars). A traditional throttle pedal can be controlled electronically via sending signals to the car’s onboard computer, the engine management system.

The primary benefit, as already mentioned, is the loss of many moving parts and their associated weight. The major drawback is that drivers tend not to perceive drive-by-wire as safe. The most significant concern is that the computer might malfunction; leading the driver to, for example, think they were applying more pressure to the brake pedal than they were. Brake failure, however, can also occur with a mechanical system.

What is Haptic Technology?

The word “haptic” is generally defined as something pertaining to the sense of touch. Humans have an extremely developed sense of touch, so “haptic technology” is a technology that makes use of the sense of touch. Specifically, it provides feedback through a person’s sense of touch. One example of haptic technology we are all familiar with is the vibrator on a cell phone.

Why Add Haptic Technology to Cars?

Haptic feedback is useful to drivers because their cognitive channels are already heavily loaded for visual and audio information. Think about it – when you are driving you are trying to keep track of the road and the other vehicles around you visually, perhaps listening to a verbal GPS (or a passenger) telling you where to go, dealing with the noisy kids in the back seat, etc. Touch, however, is used only for feedback from the vehicle itself. This means that there is more room for your brain to receive touch signals, which allows you to perform actions without diverting focus. Here are some examples of how haptic technology might be useful:

1. To provide feedback on touch screens. This allows for improved entertainment controls that don’t require the driver to take their eyes off the road. Many cars have gone back to physical controls for entertainment systems for precisely this reason. Haptic touch screens mitigate this problem by allowing for touch feedback. This is good for people who are driving alone and relying on the radio or music to keep them focused and awake. Also, studies show that if you add slight vibrational feedback when touching a screen, you look at it for less time. Physical controls can click rather than turning smoothly – this is older haptic feedback, but still works.
2. To allow for the same kind of feedback through drive-by-wire systems that are obtained through mechanical systems. (e.g. a drive could feel how much brake pressure they are applying) Making the drive-by-wire experience similar to that of the mechanical system may help with its adoption.
3. Haptic feedback could also be added to buttons on the steering column, whether they are volume up and down or turning the headlights on and off. However, vibrations as feedback on the steering column need to be programmed carefully to avoid being confused with vibrations caused by the road. Road vibration can vary in random ways and might interfere with the signals from the steering column.
4. It could make it easier to park, especially perpendicular parking. Although auto-parking technology exists, drivers tend to be a bit wary of it. Haptic feedback can notify drivers when they have turned the steering wheel the correct amount. This is particularly useful when rear cameras are blocked by a passive trailer such as a stock trailer or caravan. The same kind of force feedback could be used in low visibility, by applying a bit of force on the wheel in the direction of the next curve. Similarly, that could be used for a haptic lane departure warning (kind of a built-in rumble strip).
5. Haptic feedback in navigation. Verbal GPS directions can have noise interference and be a distraction to drivers. A haptic system that provided vibration on the appropriate side of the wheel as a driver approached a turn reduced navigation errors significantly (and thus reduced risky maneuvers). Companies have also investigated navigation signals contained in the seat.
6. Haptic feedback to alert drivers. Examples of this might include controlling the reaction force in the accelerator pedal, which is useful for helping a driver control speed, using vibration to inform drivers when other vehicles hit certain proximity levels or give a pedal vibration at the perfect time to shift gear if driving manually. Rather than taking away control, as with self-driving technologies, these technologies promise to make driving more fun.

As drive-by-wire systems become more common, haptic systems may also. The space that is no longer being taken up by manual controls and hydraulics could be used to contain some of these advanced systems. The use of haptic actuators to improve the feedback provided by electronic driving controls could enhance drive-by-wire adoption and the applications mentioned above could all improve safety on the roads.

Johnson Electric sells premium quality solenoid and haptic actuators, for all-purpose as well as automotive needs. Contact us today to find out more about our seat and seat belt driver alert platforms, actuators for touch screen haptics, and similar products, available in varied sizes and acceleration profiles.