Arduino Forum

Using Arduino => Sensors => Topic started by: Archelon on Jun 21, 2012, 12:06 pm

Title: Which Maxsonar rangefinder do you suggest?
Post by: Archelon on Jun 21, 2012, 12:06 pm
Hello I'm about to start with a robotproject, the robot will be able to scan a room in 2 dimensions with some kind of rangefinder and then do something with that data.
I've been looking for a while and it seems like the maxsonar LV-EZ series has the right price and abilities.
Now I wonder which one should I go for, the LV-EZ 0, 1, 2 or 4? I do not really understand where they specify the beam width in the datasheet so I have a hard time choosing between them.
thanks for your help!
Title: Re: Which Maxsonar rangefinder do you suggest?
Post by: AWOL on Jun 21, 2012, 12:53 pm
Quote
I do not really understand where they specify the beam width in the datasheet

What is it that you don't understand?

Generally, for mapping, I'd use the narrowest beam possible.
Title: Re: Which Maxsonar rangefinder do you suggest?
Post by: Archelon on Jun 21, 2012, 01:29 pm

Quote
I do not really understand where they specify the beam width in the datasheet

What is it that you don't understand?

Generally, for mapping, I'd use the narrowest beam possible.


excuse me, I just found the Beam width explanation file.. :P
seems like the ez4 is the one with the narrowest beam width so I'll go for that one :)
Title: Re: Which Maxsonar rangefinder do you suggest?
Post by: teckel on Jun 21, 2012, 02:52 pm

excuse me, I just found the Beam width explanation file.. :P
seems like the ez4 is the one with the narrowest beam width so I'll go for that one :)


The EZ4 also has the shortest range, keep that in mind if range is important.  I would suggest the EZ3, as it has about the same width beam but the range is much longer.

I have two problems with the Maxsonar sensors.  First, they can't detect objects closer than 6 inches, which in many cases is important.  Secondly, while it has a robust set of interface options (analog voltage, serial & pulse width), it's not compatible with most ultrasonic libraries and sketches.  This limits you to using their interface code/library or developing your own.

I've never used a Maxsonar sensor so I don't know if there's other issues (like ping speed) which could be important when used as a scanner.

Tim
Title: Re: Which Maxsonar rangefinder do you suggest?
Post by: jraskell on Jun 21, 2012, 11:30 pm
You should come at the problem from the other angle.  Ask yourself the following two questions:
What's the smallest object in the room you want your robot to be able to detect?
What's the maximum range you want to be able to detect that object at?

Once you have the answer to those two questions, look at the datasheets and find the rangefinder that most closely matches your criteria.

Just be forewarned, you may find that the one that most closely matches your criteria doesn't actually come close to matching it.