How to monitor external objects on a computer?

[SLewis]

Hi, my experience is in software and I do not really have much knowledge when it comes to hardware so apologies for my basic approach.

I am researching on behalf of an educational institute. A programme we have is to see how students interact with each other using objects, a typical scenario would be the group is given a series of objects such as blue cubes, yellow pyramids, green cylinders and so on and they are monitored on how they align/connect the objects.

Up until this point we have manually noted down how each student behaves but would like to look in to recording electronically, once we get the data stored electronically in a database we can extract it ourselves as we have the software experience in house to do so but we have never had any product of this nature before nor have we had anything similar manufactured so at present do not have the hardware expertise to create ourselves.

Our initial thought was to look for a game or learning aid which was already available but can't find anything, this could be because we do not know what it is called or that they just aren't that popular. We are in the process of talking to different electrical manufacturers and receiving quotes/briefs/estimations etc but would like to get advise to ensure we are not getting overcharged due to little knowledge and to ensure that the specifications match our requirements.

The product we envisage is a circuit board that is able to fit inside an object the size of a coin, the circuit board will have at least 2 ports/sockets/connectors (I am unsure of the actual terminology) which can be used to connect to other circuit boards, each circuit board will have a unique ID so we can monitor it. At set intervals or on request we can make a call (bluetooth/wifi would be best) which will fetch data to our database showing how the circuit boards are connected. We assume this would be two different items, the set of circuit boards which can connect together and then a main hub which connects to our computer which can receive the data and record to our database.

Please could you advise if anything like this already exists if not could you advise on the manufacturing process and what it is I am looking for?

Thanks

 

[sm625]

What I would do is embed a neodymium magnet into each of the objects. Then place hall effect sensors in the base that they plug into. As each object is successfully plugged into its proper hole, the hall effect sensor will trip. I would use a simple GPIO to USB (or RS232) board to send these signals to a PC, and write a program which monitors the GPIO and records the times each sensor was activated. I would use RS232 because I already have that hardware and low level software. But USB is obviously a bit more modern. I would avoid using anything wireless because you want something that works. (Yes I realize hall effect sensors are technically wireless, but what I mean is you want to avoid wireless communication of digital I/O signals to the PC).

It would take some testing to ensure that the neodymium could actually trip the hall effect sensor no matter which way the object was placed. This could be difficult if the objects are too large. In that case you would have to embed a magnet into each side of the object. You can seal the magnet in using colored epoxy and/or colored stickers.

 

[SLewis]

Hi, thank you for replying.

So the way you have set it up there would need to be a base to connect the objects to rather than each other? Would this work if the objects were connected to the base and the also on top of each other?

 

[EliteRetard]

I'd look into RFID/NFC as each tag can be unique.

 

[sm625]

Hi, thank you for replying.

So the way you have set it up there would need to be a base to connect the objects to rather than each other? Would this work if the objects were connected to the base and the also on top of each other?

You need some sort of base, and each sensor needs to interact directly with the base. Otherwise you're looking at a solution that is far more complex and far more expensive! You could design the objects so they can pass a signal through another and into the base. But that is still significantly more complicated.

When you initially described this project, I was not envisioning a "blue cube" plugging into a "yellow pyramid" or a "green cylinder". I was simply thinking of a blue cube plugging into a square hole in some sort of base. Likewise, the green cylinder would plug into a circular hole in the same base. If you want to plug the cube into the cylinder, and then plug that assembly into a base, you'd need to be able to transmit a signal through the cylinder and then into the base. Possible, but more complicated. I would suggest designing the system in such a way that all the objects can somehow interact directly with the base. In order to do that, you simply need all the sensors to be on the bottom half, and on the outside, of each assembly that plugs into the base.