Hi,

New to the site but here goes!

I am looking to create a system that can indicate the position of a desired item using an X Y Z Coordninate principle. Still in the dark.....So am I.

To elaborate, I have been trying to find a method of showing were an desied item is in a 2m x 0.5m square. I first though of attaching a transmitter to the item and then putting a pair of recievers in each axis ( X Y and Z ). It would then be a case of scaling the output of all 6 recievers. My thought process behind this is that the readings at each reciever will never be the same as you move further towards and/or away from each reciever. Is this a correct way of thinking about this?

If anybody can advise if I am on the right track and/or just wasting my time I would be much obliged.

Thanks

 

GPS is an X/Y Z system where it takes four satellites to determine all the desired coordinates.

 

You could make a mini GPS setup. That would be pretty interesting to see.

 

Come on guys..... GPS for a 2m x 0.5m area is going to be one very expensive piece of equipment.

I would suggest maybe ultrasonics or IR LEDS. You could have a matrix of LEDS.

 

Hi,

New to the site but here goes!

I am looking to create a system that can indicate the position of a desired item using an X Y Z Coordninate principle. Still in the dark.....So am I.

To elaborate, I have been trying to find a method of showing were an desied item is in a 2m x 0.5m square. I first though of attaching a transmitter to the item and then putting a pair of recievers in each axis ( X Y and Z ). It would then be a case of scaling the output of all 6 recievers. My thought process behind this is that the readings at each reciever will never be the same as you move further towards and/or away from each reciever. Is this a correct way of thinking about this?

If anybody can advise if I am on the right track and/or just wasting my time I would be much obliged.

Thanks

You could use ultrasonic sensors as suggested, have a receiver setup in each corner of the square, and have the transmitter on the object (Just as you had thought off) and do some TOF (Time of flight) calculations to figure out which receiver it is closest to, etc.

Or use an IR LED as the transmitter, and use photodiodes as receivers, but this way may be a little more complex than doing TOF calculations since you would have to use analog inputs for the sensors and read the varying analog input depending on how far the transmitter LED is....


B. Morse

 

What degree of precision do you need? If you can use a magnet in the object, Hall effect sensing might work very well - http://www.analog.com/en/sensors/hall-effect-sensors/ad22151g/products/product.html

 

Come on guys..... GPS for a 2m x 0.5m area is going to be one very expensive piece of equipment.

The GPS comment was to see the positioning theory, not necessarily use GPS as the source. Besides, GPS isn't that good of a system for the area of interest.

 

You could use ultrasonic sensors as suggested, have a receiver setup in each corner of the square, and have the transmitter on the object (Just as you had thought off) and do some TOF (Time of flight) calculations to figure out which receiver it is closest to, etc.

Or use an IR LED as the transmitter, and use photodiodes as receivers, but this way may be a little more complex than doing TOF calculations since you would have to use analog inputs for the sensors and read the varying analog input depending on how far the transmitter LED is....


B. Morse

Thanks very much for the info.

I was interested when you mentioned ultrasonics as I have only seen large versions ( Microsonic I think ) and the item that I want to attach it is about 20mm x 40mm x 20mm. Can you elaborate further on the 2 principles that you mentioned on your reply?

I have also never heard the term TOF but have a limited understanding of scaling analog inputs ( Distance measurement using a PLC input card )

Once again thanks for your replys

 

TOF is time of flight. You send a pulse and measure the 'time of flight'. That is the time it takes for the signal to leave the transducer hit the object and return to the receiver.

Wikipedia probably has a much better explanation of time of flight.



I was right, they do:

http://en.wikipedia.org/wiki/Time-of-flight