Ultrasonic interference

I am using multiple arduino nano controllers and each single ultrasonic sensor is connected with each arduino. My project is to attach different sensor modules on the storage racks to detect the picking of an objects. I want to make sure there would no interference between neighbouring sensors. So how do I avoid interference or crosstalk between sensors?

PS. I am using I2CXL Maxbotix sonar sensor.

You have to synchronize them so the echo from one has died out before the next one fires off.

Paul

Have a separate sensor that is used just to receive ultrasonic signals, a read only sensor. You know when your object sensor has fired, the read sensor can then be used to detect residual signals and when the residuals fall below a certain level fire the next sensor.

But the problem is each sensor modules are not connected with each other. They are seperate module with controllers and attached on the shelves. So all the modules must run at a same time. And it’s not possible to synchronise all the sensors because there are many independents modules and wirelessly attached. Basically, it’s a pick to light system.

Yasir002:
But the problem is each sensor modules are not connected with each other. They are seperate module with controllers and attached on the shelves. So all the modules must run at a same time. And it’s not possible to synchronise all the sensors because there are many independents modules and wirelessly attached. Basically, it’s a pick to light system.

No. The problem is in the design of the entire system.

Paul

I think you didn’t get my point. Actually it’s a pick to light system. In warehouse, there are multiple storage racks and on each shelf wireless sensor module is attached. Each module contains the led which guide the user to go to the particular rack according to the sequence provided by the server. When the user picks up the desired object from the rack, the ultrasonic sensor attached on the module will detect the hand motion that the user has successfully picked up the object and send a flag to server. Now the user wait for another sequence but this time it could be other rack with same operation. I just want to make sure that there is no interference between the neighboring ultrasonic sensors. As ther many storage racks in warehouse with modules attached.

I got you point just fine. I wonder how the system was tested before management gave approval to turn it on for production.

Paul

Actually it’s the part of my master thesis. Could you please guide me what should I do?

Yasir002:
Actually it’s the part of my master thesis. Could you please guide me what should I do?

Please help me. Is this a paper system project or is it real?

Paul

Actually it's the part of my master thesis.

I suggest that you ask your thesis advisor for guidance, and of course you will cite any help you get from on-line forums in the thesis.

It is paper system project right now but have designed a prototype model for testing. But it will be implemented by company in future if it works successfully.

Yasir002:
It is paper system project right now but have designed a prototype model for testing. But it will be implemented by company in future if it works successfully.

Then I suggest you think why you are designing a hobby system to be used in an industrial setting.

Paul

I would go for light rather than ultrasound. Have a break beam sensor at each position makes it much easier to prevent interference with one another.

Or an IR based proximity sensor at the back of the rack should also do really well.

By the way, you're not registering successful picking of products. You're registering visits to the specific positions which is not necessarily the same. You will have the requirement of more than one product from a specific position. You will have empty positions because someone miscounted when stocking.

Idahowalker:
Have a separate sensor that is used just to receive ultrasonic signals, a read only sensor. You know when your object sensor has fired, the read sensor can then be used to detect residual signals and when the residuals fall below a certain level fire the next sensor.

Doesn't work like that, individual reflections come back with no warning.

Wait long enough for all targets to be out of effective range, that's a time dependent on the range
of the sensor and the speed of sound.