How to know if device is returned?

Good day everyone, we are currently making a receiver device for our thesis. This device is portable and be carried by the user. What is the best method to do to know if the device is returned to our cabinet? we are using an arduino nano and a gsm module. We plan to use the usb port of the arduino to know if the device is returned. What sensors or program can be used to know if the device is plugged back in? Thanks in advance and more power.

Hi,
Can you put an RFID tag on the "device" and RFID reader in the cabinet?

Hope it helps..

Tom.. :slight_smile:

ram_vb:
We plan to use the usb port of the arduino to know if the device is returned.

That seems a strange statement when you have no idea if it can work. I certainly don't know how to make that work without there being a conversation between the device and the PC it is connected to.

What about each device having a designated space and putting a microswitch on the base of the space so the switch is pressed when the device is in place.

...R

You could put a Serial.write("device returned") line to run in your code every few seconds...

then when plugged into your cabinet connected to eg realterm on a pc, you'll know it's home...

regards

Allan

You could put a sign-out sign-in procedure in place and put that responsibility on the user.

When the device is plugged in to the cabinet USB, can it communicate it's presence and ID occasionally? The USB isn't just for power (a charger) is it?

Measuring the USB current will tell you that some kind of device is plugged in, although not necessarily the device you were expecting. You could try characterising the current draw as a kind of fingerprint unique to your device.

Robin2:
That seems a strange statement when you have no idea if it can work. I certainly don't know how to make that work without there being a conversation between the device and the PC it is connected to.

What about each device having a designated space and putting a microswitch on the base of the space so the switch is pressed when the device is in place.

...R

at first we had planned to do this but we need to charge the battery of the device so we need to connect the device in order for the battery to be charged after using.

GoForSmoke:
When the device is plugged in to the cabinet USB, can it communicate it's presence and ID occasionally? The USB isn't just for power (a charger) is it?

yup the usb is not just for charging. it must charge the battery inside and detect that the device is returned as well. any idea? thanks

ram_vb:
yup the usb is not just for charging. it must charge the battery inside and detect that the device is returned as well. any idea? thanks

If that means that you plan to plug the device onto a USB cable connected to a PC then you could have a program running on the PC that listens for a message from the device. That could be a simple message such as Serial.println("Device XYZ is here"); included in setup()

...R

Robin2:
If that means that you plan to plug the device onto a USB cable connected to a PC then you could have a program running on the PC that listens for a message from the device. That could be a simple message such as Serial.println("Device XYZ is here"); included in setup()

...R

oh okay,but is it possible to do something like if the device is returned something will happen like opening of a lock. we have 3 devices and have 3 locks. thanks

Hi,

oh okay,but is it possible to do something like if the device is returned something will happen like opening of a lock. we have 3 devices and have 3 locks. thanks

So want to unlock the door to where the device is to be stored/recharged?
So you need to sense the device before it is plugged in?

RFID....

Tom... :slight_smile:

ram_vb:
oh okay,but is it possible to do something like if the device is returned something will happen like opening of a lock. we have 3 devices and have 3 locks. thanks

If you connect the device to the PC and if the PC detects it then your PC program could send a signal to another Arduino that controls the locks.

What is the purpose of the locks?

This idea of yours seems to change every time anyone suggests something to you. Why don't you lay out the entire requirement for us if you want useful advice.

...R

First figure out how to detect when the device is taken away.
Then the return part will be easy.

ram_vb:
oh okay,but is it possible to do something like if the device is returned something will happen like opening of a lock. we have 3 devices and have 3 locks. thanks

What operates the locks?

Device can identify itself to the PC every second if needed.

Why do you want to do something clearly beyond your capabilities to plan?

Does 'any ideas' mean 'give me the design and code'?

Robin2:
If you connect the device to the PC and if the PC detects it then your PC program could send a signal to another Arduino that controls the locks.

What is the purpose of the locks?

This idea of yours seems to change every time anyone suggests something to you. Why don't you lay out the entire requirement for us if you want useful advice.

...R

the purpose of the locks is for the cabinet where the devices will be stored

Robin2:
If you connect the device to the PC and if the PC detects it then your PC program could send a signal to another Arduino that controls the locks.

What is the purpose of the locks?

This idea of yours seems to change every time anyone suggests something to you. Why don't you lay out the entire requirement for us if you want useful advice.

...R

Sorry for the inconvenience. The thesis that we are making is a modification of the current charging station. The thing that is new about this charging station is that it will alert the user once the paid time is finished. We will use a gsm receiver, buzzer, arduino nano and battery to build the notification device. A coin slot will be used as the device for the payment. Magnetic locks will be used to secure the devices that will be charged. There will be 3 slots for charging and 3 slots where the notification device will be placed. If a user wants to charge his phone, the notification device must be taken by the customer in order for him to be notified later on. Our main concern is in the process of returning our notification device. We want the customers to return our notification device properly before the machine will release the phone. The agreed way to do this is that the notification device must be plugged in to the usb cable attached to a computer in order for the program to detect if the notification device was returned and at the same time charge the battery inside. The user interface was built through Visual Basic. The magnetic locks will be controlled by a relay that is controlled by an arduino. The main problem is that how does the visual basic detect if the device is returned. This is the complete details of the project. Everything is already done except for the detection part. Thanks and more power

You could have saved a great deal of time if you had provided that explanation in your Original Post rather than in Reply #16.

Will the notification device be based on an Arduino?

Rather than connecting the notification device directly to a PC through a USB cable why not connect it to another Arduino that can interrogate it and send suitable messages to your PC.

I suspect you could design some mechanical system that would only allow you to remove the notification device if a phone was inserted in one slot and would only allow the phone to be removed if the notification device was inserted in its slot. Steel sliding doors etc.

…R
PS you must be planning to have a very high price for charging a phone if it is to be worth all this much trouble :slight_smile: Why not just let them charge for free - or for a small payment that provides power for N minutes.

Robin2:
You could have saved a great deal of time if you had provided that explanation in your Original Post rather than in Reply #16.

Will the notification device be based on an Arduino?

Rather than connecting the notification device directly to a PC through a USB cable why not connect it to another Arduino that can interrogate it and send suitable messages to your PC.

I suspect you could design some mechanical system that would only allow you to remove the notification device if a phone was inserted in one slot and would only allow the phone to be removed if the notification device was inserted in its slot. Steel sliding doors etc.

...R
PS you must be planning to have a very high price for charging a phone if it is to be worth all this much trouble :slight_smile: Why not just let them charge for free - or for a small payment that provides power for N minutes.

yeah the notification device will be arduino based. The thesis requirement is that there must be something new. But thanks for the advice, will consider your opinion. Thanks again :smiley:

This just gets "better and better". A coin-op personal device charger that lets you carry a pager around the mall to tell you when to come back and get your device by returning the pager. That won't get hacked or vandalized and Trump will never win the pres... oh.. wait..

Where would such a thing be needed where people have coin enough to make it worth installing and need to leave their own device? What will happen when something fails and the customer can't get their phone back for any one of many possible reasons including vandalism?

Hey as long as the thesis requirements don't include "It must be practical." then what the heck, right?

Oh btw, I hope they don't make you actually build anything. That would teach students to waste.