soccer ball detection and positioning

soccer ball detection

i am doing a project in which i need to detect whether a soccer ball has crossed the goal line or not.
i was just thinking if this is possible.
placing a receiver(s) near the goal post and a transmitter inside the ball.
i will need an IC which can be used for transmitting purposes , since inside the ball , complicated circuits are to be avoided.
using RFID technology inside the ball along with the transmitter, we can detect whether the ball has crossed the line or not.
i believe the detection is similar to the one used to prevent shoplifting.. i.e a person walks through a particular path (ball crossing the goal-line in this case)... and a signal can be transmitted from the ball to the receiver as soon as the ball crosses the line.. and i can flash an LED or something to show detection.
if this is possible, i need some guidance on the IC to be used for transmission purposes in this case.

Re: soccer ball detection

You might not be able use a simple RFID approach, as the goal line is very long, and the antenna would have to be very close to it for the RFID to be activated.

A concern is: just how accurate do you want the system to be. What if the ball were very close to the goal line, say 1 cm away, but does not actually cross. Can you stand a false alarm, or do you neet more accuracy than that?

Re: soccer ball detection

regarding the accuracy, i dont think 1cm error will be of much concern.
since i am new to all this, i feel that.. at this stage, the simpler the project, the better.
right now,i would be satisfied if i am able to do the detection (with 1cm error). and later on i would try to improve it and make further advancements .

Re: soccer ball detection

I don't think you understood. 1 cm accuracy would be phenomenally good, and hard to do. 1 meter accuracy would be very easy to do. What do you need?

soccer ball detection

Hi,
I think thes is a very courageous project!
For me is a problem with the transponder as first!
1,
How are you thinking to fix/place it in the ball pls?
It must be central in ball and has very strong stresses by all shoes &blows...
2,
the goal/gate has a standard width of 7.32m, these must be the data for your coils length, can be (as goal line) exact 12 cm wide_nice measures!
3,
The energy for the reader coil & hes sensing distance?
If Im right, & assumed it will work in HF band, it will sens (theoretically) from ca. 7-10meter, I think you dont need it-or?
K.

Re: soccer ball detection

The soccer rules require the ball passing with the entire circumference the goal line, to be considered a valid goal.

So, your circuit must be very accurate, otherwise the players (and not only) get upset.

In my opinion a radio circuit cannot be such accurate unless you are using a microwave transponders (f >10GHz).

On the other hand the weight of the soccer ball must be between 410 grams and 450 grams, so you have less than 40 grams allocated for the weight of your circuit.

https://en.wikipedia.org/wiki/Football_(ball)

Re: soccer ball detection

@biff44
okay.. i got it now.
1 meter seems too much... i would like it to be much more accurate(max 2-3 cm error) but simple..
@karesz
i did some research regarding fixing the circuit inside the ball.. adidas had written it somewhere that after the stitching is opened , if the circuit is placed in the centre, the flight and speed of the ball will not be affected.
regarding the receivers and transmitters ICs to be used.. i need to do some research on that.. i am still not sure about them..

Added after 5 minutes:

@vphone
in order to not exceed the weight limits, apart from the transmitter IC , only a detector will be used inside the ball..
after this detector detects that its a goal, signal would be transmitted to the receiver near the goal post.
this is what my plan is..plz correct me if i m going wrong..

Re: soccer ball detection

Well, it is obviously a difficult problem, but certainly is technically solvable. I have done position location systems at 6 GHz with 2mm accuracy over a 2 meter cube, for instance. THAT was with an active transponder in the moving object, though.

I would list all the requirements down as a start. G forces, shock, etc.
I would probably use microwave frequencies. Would probably harvest the kinetic energy of the soccer ball to power the circuitry (so you would not need the weight of a battery). Would make the whole thing very small/lightweight---like a single transponder chip with a fabric antenna near the outside skin of the ball. You would have to sense the position/orientation of the ball to actually calculate if the center of the ball went over the goal line. You will need LOTS of antennas on the actual goal post, and some pretty high speed processing circuitry doing parallel computations.

You can use the fact that you do not need to do the computations in real time. i.e. if you get the result that the ball crossed the goal line say 5 seconds later...that is still ok. You can stop the game and call the goal.

Rich


Added after 5 minutes:

btw, the traditional methods of doing such a project are
1) stereoscopic camera spotting a recognizable thing, like super-reflective dots painted on the ball skin
2) low frequency magnetic grid detection
3) microwave position locating

Other methods, like zigbee coding position locating engine, usually are not fast or accurate enough.

Re: soccer ball detection

rama_ynwa said:

...regarding the receivers and transmitters ICs to be used.. i need to do some research on that.. i am still not sure about them...

Click to expand...

Past time I was involved in some atypical RFID projects, I think thes is as Idea good, but I cannot see a chance to realize it:-(...

... only a detector will be used inside the ball...after this detector detects that its a goal, signal would be transmitted to the receiver near the goal post.
this is what my plan is..plz correct me if i m going wrong..

Click to expand...

These is me clear, the only real solution is in the ball a "passive TP" (TransPonder) solution.
I can belief that a SAW-system is real good for that!
You can have some components from telemetry deliverers & at 900MHz their are realized on the mart!
A SAW is absolute passive-a resonator only. Here is "The Trick" by an good idea for some antenna solution (installed onto/into the gate construct), that can power it so that your balls detection is only over the "Goal-line" possible (these is the 12 cm broad line)... If you has a good idea for that; I think its to patent!
K.

i went through some other methods of doing this project..
i have decided to use active rfid tag (transponder) inside the ball..
i would be happy if someone could help me on the circuit diag. of an active rfid tag ...
i am unable to find it ...
thanks in advance