Magnetic Field Sensors and Soccer Balls

There are "light curtain" devices sometimes used for guarding machinery. An arrangement of mirrors makes a beam of light pass in parallel paths across an opening. Interruption of the light, as by putting a hand through, shuts down the machine.

In your case, the goalie or other players might interrupt the beam, generating a false positive. Some kind of computer program might be able to sort out the difference.

This is just one idea among many that might be possible. Interesting project--best wishes of success!

There is a US patent for a similar application for hockey pucks- I remembered it from some time ago and found it on Google :

Electromagnetic transmitting hockey puck - Patent 5564698

An electromagnetic transmitting hockey puck according to claim 1, wherein said electromagnetic transmitter includes a shock sensor which turns on said ...
www.freepatentsonline.com/5564698.html -

Edmund from NJ

thanks for the link

according to me the soccer ball that i have to use should have an electromagnetic transmitter... and the referee (in this case) would be having the receiver..

i am still not clear how to link the goal line with this soccer ball.. am i supposed to use an antenna whose radiation pattern covers only the goal area?? this antenna will radiated em waves.. which can be detected by the ball ...

correct me if i am wrong here..

one way to detect if the soccer ball has crossed a line is as follows:

1--locate information on RFID radio frequency identification devices.these come in all kinds of formats ,with or without a battery, They are similar to the sensor strips used to protect valuable items from being taken such as fur coats etc from a stiore or other thing s.

2----The ball has a thread inside it going from one e nd to another and through its center where the RFID is located,you will have to bury a wire as the antenna to receive the signal...this again is similar to the pet collar that is known as the invisible fence

hatim carim,

I'm afraid that will also create false positives, due to proximity, as in the case of a ball hitting the post, but bouncing outside of the goal.

OP needs something that confirms that the ball has passed the post into the net.

cameras posted directly overhead the goals would easily confirm a goal, but you'll need an instant replay, in slo-mo to do that. perhaps a program can be written for that, as well, similar to boxing's COMPUBOX. if that software can record the number of punches thrown and landed, surely it can count oftentimes less than a handful of goals that occur in an hour or so.

thanks for your advice..

i am clear with the role of the RFID(distinguish soccer ball from other external objects using RF) in this case.

i believe that i will be able to understand how to physically represent RFID and the antenna in my soccer ball only when i purchase them.

i have some doubts with the working of the antenna and hence the exact working of my model.

i know that this whole detection process is going to use radiowave frequency and the antennas are going to be used for transmission and detection. The antenna will operate at RF.

my question is that... how exactly is this transmission/reception going to take place

is there another antenna near the goal line set in such a manner that its radation spectrum just covers the entire goal area.. and it synchronises with the soccer ball antenna frequency when the ball crosses the goal line.. and hence detection is done?

please correct me if i am wrong here..

please bear with me since i am a bit new to this..

regards

Hello, rama_ynwa, and welcome to CR4.

It seems to me that the best way to do this would be with geo-location. The soccer ball would have a GPS-type transmitter in it, similar to what some transportation companies use to track their vehicles. Rather than using satellites for positioning, however, a local RF source (master) could be set on the sideline. A modified GPS software package could then continuously track the position of the ball relative to the master. With such a short distance to the master, I suspect you could get very good positioning data in 3 dimensions.

Before the match, the exact location and extent of each goal plane would need to be identified to the software. Then, if the ball crossed the plane within the goal boundaries, the software would send a signal to a small receiver carried by the official (or perhaps a large air horn for rabid fans?).

With digital encoding of the RF signals, you could place several of these units on adjacent fields without interference. I'm thinking of the youth tournaments in my area, which have as many as 40 playing fields side-by-side.