Hi,
please see photo below to understand what im talking about
Does anyone know what kind of sensor is being used to detect whether a basket has been scored on these machines (see photo in link)?
When I google motion sensing and arduino, it mostly comes up with PIR sensors and projects aimed at detecting the presence of people or animals. I would like to detect moving objects like in the example below.
I would like to detect objects smaller than a basketball but also moving at speed.
Essentially I want to detect when something has passed through a hoop. But something smaller than a basketball.
Thanks for any help
(ideally i would like to detect anything that passes through the hoop, from things 4cm across or smaller, to a full sized basketball.)
Would beam break detection work? i.e. facing the emitter and receiver in the same direction, facing away from the back board under the hoop, when something passes through, the beam will be reflected back, triggering the ir detector? Or using a photoresistor to detect sudden decreases in light as an object flies past it at close proximity?
obviously i only want the circuit to be triggered if something passes through the hoop and not by people walking past, as may be the case with the IR break beam set up.
Might ultrasonic work, i.e. could I use that to calibrate the distance at which a detection is considered a hit, and not someone walking by.
is there any chance of one or multiple of these working? : http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&item=131201356019&fromMakeTrack=true&ssPageName=VIP:watchlink:top:en
This is a light curtain application (meaning the requirements are similar regardless of the purpose) .
Google Omega Light Curtain
There's IR led transmitters and IR photo transistor detectors. They have to be mechanically aligned very accurately. The mounting
needs to be such that the angle can be adjusted. Once they're calibrated then they are very reliable.
Didn't you already post about this a few weeks ago, or was that some other person? The sensor in the first photo is an untrasonic distance sensor, also commonly called a "ping" sensor. It literally "chirps" an ultrasonic pulse out of one of the cans. In theory, the pulse echos off an obstruction and is received back to the other can. You typically count how long it takes for the pulse to come back, and from there it is a simple mathematical formula to calculate the distance. These are commonly used for robots to help with collision avoidance or for anything where you want to attempt to measure the distance from something. I've got some experience with them. I don't think they will be a good sensor for you to use on your hoop machine. First, they are prone to errors... The sound radiates outward and pulses can be echoed off a wide range of things... the further out the pulse goes, the bigger the chance the pulse will echo off something not directly in front. For example, I attempted to build a parking assistant for my garage. The pulses were constantly bouncing off other things in my garage causing false distances. Also, these don't work well if the surface they hit is curved or angled away. They work best with the object they hit is flat and directly facing the sensor. Case in point, my wife's car has a lot of curves on the front of it. I could never get the sensor to report correct distances with her car, yet it worked fine with my car.
As I mentioned in the other thread, the best way to do this is with an IR proximity detector or IR break beam. If you had it mounted just under the rim angled at a downward angle, this would probably eliminate false triggers. The idea is there is an IR emitter that shoots infrared light that gets reflected back only if a ball is in the way. Since the beam won't be reflected back until the ball is more than halfway in, you should be able to prove the ball is going through. You're probably going to have to adjust the angle until you get it right.
raschemmel:
This is a light curtain application (meaning the requirements are similar regardless of the purpose) .
Google Omega Light Curtain
There's IR led transmitters and IR photo transistor detectors. They have to be mechanically aligned very accurately. The mounting
needs to be such that the angle can be adjusted. Once they're calibrated then they are very reliable.
Would something like this work, if I mounted it on an adjustable mount like you say?
Xpendable:
Didn't you already post about this a few weeks ago, or was that some other person? The sensor in the first photo is an untrasonic distance sensor, also commonly called a "ping" sensor. It literally "chirps" an ultrasonic pulse out of one of the cans. In theory, the pulse echos off an obstruction and is received back to the other can. You typically count how long it takes for the pulse to come back, and from there it is a simple mathematical formula to calculate the distance. These are commonly used for robots to help with collision avoidance or for anything where you want to attempt to measure the distance from something. I've got some experience with them. I don't think they will be a good sensor for you to use on your hoop machine. First, they are prone to errors... The sound radiates outward and pulses can be echoed off a wide range of things... the further out the pulse goes, the bigger the chance the pulse will echo off something not directly in front. For example, I attempted to build a parking assistant for my garage. The pulses were constantly bouncing off other things in my garage causing false distances. Also, these don't work well if the surface they hit is curved or angled away. They work best with the object they hit is flat and directly facing the sensor. Case in point, my wife's car has a lot of curves on the front of it. I could never get the sensor to report correct distances with her car, yet it worked fine with my car.
As I mentioned in the other thread, the best way to do this is with an IR proximity detector or IR break beam. If you had it mounted just under the rim angled at a downward angle, this would probably eliminate false triggers. The idea is there is an IR emitter that shoots infrared light that gets reflected back only if a ball is in the way. Since the beam won't be reflected back until the ball is more than halfway in, you should be able to prove the ball is going through. You're probably going to have to adjust the angle until you get it right.
Hi,
Thanks for all the advice was a thorough and enlightening read. The ultrasonic sensors sound a bit dodgy then.
Il take a look at the break beam and ir proximity detectors. Il order a few different ones in and have a play around to see what I can get working.
Thanks again for taking the time to give this thorough advice.
Would something like this work, if I mounted it on an adjustable mount like you say?
yes, but you need to understand what I mean by "adjustable mount". The emitters are adjustable but the detectors are fixed.
By "adjustable" I mean there is a tiny pc board mounted on a pivot. There are screws that go in and out adjusting the pivot angle.
Would something like this work, if I mounted it on an adjustable mount like you say?
By "adjustable" I mean there is a tiny pc board mounted on a pivot. There are screws that go in and out adjusting the pivot angle.
Can you buys these ready made for purpose? Or will I have to create something myself?
Thanks again for all the help, just waiting for some parts to arrive at the moment and testing everything out.
The ones on this page are probably the only ones you can afford . There are probably industrial (as opposed to hobbyist) versions but they would cost more than you would be willing to spend.
The mounting hole is for a standoff. The standoff is mounted on a pivot with screws that allow you to adjust both axis a few mm.
You have to be creative.
