Hi
What options do I have if I want to use Ultrasonic or IR sensors that have huge ranges. About 500m would be optimal.
In terms of cost, what would that turn out to be?
Thank you in advance.
place as many as necessary to cover the area.
Edit
Maybe there are some microwave PIRs
Hi friend,
it depends on the uses, WHY you need that Ultrasonic sensor,I mean for what kind of project? haven't seen 500m ranged Ultrasonic or IR sensor yet, unless you mean 500cm=5M
About costs they are cheap,($20~$50) and even more than $50 sometimes as for what uses you need it and what company you buy it from.. on my side am using parallax ones... about the range you don have to worry as all distance sensors are simply programmable by Most Arduino boards (e.g The Arduino Uno/R3) to ANY ranges according to your project needs..
Hope it helped!!!
About 500m would be optimal.
Imagine how loud you'd need to shout to be heard 500m away.
Now imagine how loud you'd have to shout and how sensitive your ear would have to be to hear a reflection of your shout after a round-trip of 1km.
Also think of how wide the "beam" of your shout would be at 500m range, and all the objects it could bounce off along the way.
@LarryD, What do you mean by "place as many to cover the area"?
@sijabaraka, I mean 500m. This is a project that is for a science fair, and I am going to need to install it on a vehicle, hence the large range.
Are there no options then? Cost is not a big issue, but still...
If that is the case and you are going to install it on a vehicle, you will need to apply 'DOPPLER EFFECT' theories,,,On your case this will work,, To such a distance range normal Ultrasonic Ping Sensors and PIRs face difficulties as the whole work is going to be SO complex and INACCURATE at all..
check out DOPPLER EFFECT.
If you are trying to measure distance, over 500 meters - ultrasonic/IR sensors won't cut it. You are going to need either radar or LIDAR. Neither of these will be cheap for the distance needed (radar won't be cheap because you are going to need very high speed for such a short distance; LIDAR won't be cheap because 500 meters is a large distance for most LIDAR sensors - which aren't typically cheap to begin with).
There are low-cost, single point LIDAR sensors out there, but most are limited to 100 meters or less. 2D LIDAR systems that are anywhere near close to "affordable" (on the used market at least) - are only good out to about 50 - 80 meters. 3D LIDAR - well, forget it - you likely can't afford it, unless you have a large budget at hand, or are willing to sacrifice scan speed.
Would it work out any cheaper if I just needed the distance measurement? I just need to know the distance of the obstacle from the source. I do not need the more sophisticated functions.
Initially, I thought ultrasonic sensors send out waves in a straight line, all the way to a reflecting substance (if any) and the waves get reflected in the same line back to the receiver. But I am not sure of this. If not this, do they send out a wave which gradually becomes wider, and then gets reflected if it encounters an obstruction?
Do any of the available distance sensors send waves in straight lines, to the reflecting substance and back?
What about using sensors with a 100 m range instead? Would that work out more cost-effective?
I thought ultrasonic sensors send out waves in a straight line,
They send out sound in a conical beam, spreading wider all the way to the target . . . and back.
As the beam spreads, it weakens.
If you're lucky, it will strike a hard object square-on and a tiny fraction of the transmitted energy will head back towards the receiver.
If you're unlucky, the outgoing beam will strike a hard object at an angle, and the reflected energy will reflect away from the receiver, or the beam will strike a soft object (bush, human, animal . . .) and an even tinier amount of energy will be reflected back, or scattered.
Tell us what you're trying to do, not how you think it ought to be done.
I was going to use an ultrasonic sensor for my project where I needed to know the exact distance of an obstruction in the path of a moving body (to which the sensor is attached). But I needed a large range (because the sensor will be used in vehicles like trains) and read that ultrasonic waves won't be able to detect the obstruction at a large distance quite as well. Because they spread out, there might be some disturbances (unwanted elements being detected). So I thought I'd ask if there were alternatives to ultrasonic sensors that still have the large range, or if the ultrasonic sensor itself can have a large range, and detect only the obstructions (if any) that lie more or less on the path of the waves (so they would be straight in front of the source of the waves; the moving body).