Hey guys, I need a sensor or module that can help me determine the distance between user and an object. I'm using arduino uno. As the distance decreases, I want the buzzer to increase frequency. Kinda like a metal detector. The coding is no problem but I do not know what modules could get it done. It will be used indoors, it is to guide a person to a certain item via sound. I thought about using GPS but I wouldn't know which libraries to use or which module to get. Please help.
Use the magnifier symbol up to the right in this window and do some search. There are a number of such requests every week and the answers are nearly always negative.
Gps has an accurazy of some 10 - 100 meters. I have recieved plots from a stationary GPS receiver that points "all over the place" during the day.
There is a way, if needed additional GPS transmitters exist in the neighbourhood, You can pay for this special services. Than the accurazy could be like one meter. How the repeatability is, I can't say.
This is for a school project, I do not need it to be that accurate. I just need it to be able to demonstrate the idea in front of my professors. If it had an accuracy of 1 km, that is fine.
I disagree with Railroader.
I think you should use the magnifier symbol up to the right and do some search. See that many people suggest that the Posyx system provides exactly what you are asking for. Then go see the price of the Posyx system and scream.
Assuming OP has a budget like NASA Your reply might be of use…….
I think Vince explained it adequately in the final sentence. 
In short, there is a way to do it, essentially only one way, and you must seriously want to do it where "serious" is measured in $ units. 
What actual distance are you looking for? Indoor/outdoor?
Indoor. But like I said, I am gonna present it to a school board and I don't need it to be accurate or anything, I just want it to be able to tell that the object is getting close. Like in a 2 m radius.
enginefreak:
Indoor. But like I said, I am gonna present it to a school board and I don't need it to be accurate or anything, I just want it to be able to tell that the object is getting close. Like in a 2 m radius.
Maybe this.....
You can do quite accurate ranging with a combination of sound pulse and radio pulse. Emit them at the same time, measure when it arrives by the other object, time difference gives the distance.
What is the 'object'?