Tag Archive: car


Nature inspired ultrasonic distance measurement

An animal that uses ultrasound is the bat, they use it to hunt at night. A lot of animals hunt in the dark, like cats and have special eyes to see in the dark. But because insects are too small to hunt even with that kind of eyes, the bat uses Ultrasound to locate insects to hunt on.

animal ecolocation
So he uses his ears to see (= echolocation). Not only bats use this method, also dolphins and whales. It’s even possible to do it as a human, Daniel Kish is blind from the age of 13 and has adapted to this, by learning himself echolocation.

human-echolocation-in-action

Not only nature uses echolocation, also submarines and cars use it, like you see on the first picture. Submarines can use sonar to check the depth of the sea or to see other objects in the neighborhood. Because we use ultrasound in our thesis I find it more appropriate to talk about the echolocation in cars.

example of park assist

Now a days every car has park assistance on it,  like you see on this picture there is already a lot of evolution in this sector.

evolution in ultrasound sensors

For the ones that don’t know how it works, the sensor transmits a burst and then he times how long it takes to receive the echo/reflection of the burst. Then he uses this time difference in combination with the velocity of sound to calculate the distance.

Because the sensors are used outdoor, they need to be waterproof. For this reason they opt for enclosed sensors, that can both transmit and receive. These types are normally less sensitive, but more robust.

An important factor, they need to choose in the application is at what frequency to transmit. Transmitting at a high frequency, makes your signal more directive, what is better to prevent interaction with the ground. For the same reason asymmetric types are used, sensors that have a bigger horizontal range than they have vertical.

directivity of higher frequencies

 

 

 

I hope you see that nature inspired this invention, you could see it as an example of biomimicry.

See you next time.

Detecting raindrops

I was driving in my car and it started to rain. My windscreen wipers automatically started to work and I was wondering how it works. So after searching I found a good blog post that explains how it works. Here you see a schematic representation of its internals:

01-rain-sensor-working-principle-reflection-of-infrared-light-electro-luminescent-diodeSo, on the left you have a LED that sends out a beam of light and depending on the amount of light that is received on the right side, the output gives a certain value. When a raindrop lies on top of the windscreen above the sensor, a portion of the LED light beam is deflected to the outside and therefore the receiver receives less light and this difference is visible at the output. This is then used to adjust the speed of the windscreen wipers.

So this can make the live of a driver easier. There can be a lot of possibilities to use this sensor for, like closing the roof of a convertible or turning on the lights during heavy rainfall.

Are there other possibilities to use the sensor for, that you can think of, which can ease the job a driver?

 

 

 

 

Extra! Extra! Read all about it!:
A new innovation in the automotive industry was recently announced, McLaren are going to use Ultrasonic waves to clear the windscreens of their super- and hypercars.

mclaren-ultrasonic-wipers

These Ultrasonic Waves have multiple advantages like, they don’t distract the driver and it is more aerodynamic than the standard windscreen wipers. The Sunday Times was the first to publish article about this topic so if you have an account I would certainly recommend you all to read it.

This new development shows another application of Ultrasonic waves than the distance measurement we do in our Thesis.