What Bats Have to Do With Your Car’s Parking Sensor

Parallel parking has long been one of the more frustrating aspects of driving a car. With the advent of parking sensors in the early 2000s, however, the job got a lot easier. No longer are drivers forced to twist their necks and make an educated guess at the distance between them and the car or wall behind them.

Countless bumpers have been saved over the last decade and a half since the parking sensor went mainstream, but how do they work?


The answer has something to do with bats.

The Ultrasonic Parking Sensor



It is common for engineers to look to nature for inspiration. Velcro, for example, was invented when a Swiss engineer took a closer look at the seeds of a burdock plant, known around our way as “hitchhikers.” He noticed the hook structure and then replicated it using nylon to create what we know today as Velcro.

So, when engineers were trying to develop a system that would help drivers locate something they can’t see, like the front bumper of a car behind them, they looked to an animal that needs to navigate without the benefit of sight–the bat.

Bats use a system called echolocation to navigate their worlds, since they are effectively blind and often move around in the dark. They emit high-frequency sounds and then use the time it takes to reverberate back into their ears to determine how far away they are from an obstacle.

Ultrasonic parking sensors work in almost exactly the same way. They emit high-frequency sound waves which are inaudible to the human ear. Then, a sensor detects how quickly those waves take to get back to the car. It also detects any changes in the sound wave. The sensor then triggers an audible alarm to alert the driver to the distance.

The Electromagnetic Parking Sensor


More and more, manufacturers are moving to electromagnetic parking sensors. They are not dissimilar to ultrasonic sensors, but they emit electromagnetic waves rather than sound waves. This has an advantage over ultrasonic sensors in that they can better moving objects–an important feature for backing out of parking spaces in bigger lots where cars may suddenly appear behind you.

What Does the Future Hold?



The future of parking–and really of all driving–is full automation. Already vehicles like BMW’s i3 feature fully-automated parking, with 360-degree cameras, sensors, and even lasers that guide the vehicle into a parking space.

As we move towards self-driving cars, however, parking will become fully automated. Beyond that, it may become a thing of the past altogether. Some futurists believe that once cars become fully automated we may move away from private ownership and towards an on-demand model. Imagine that all cars were Ubers and far less expensive. Since they would continually drive around picking up passengers and taking them to their destination, there would be no need to park at all except to refuel or recharge. So many exciting possibilities.

For more car knowledge, stay tuned to the Strutmasters blog.