Ultrasonic Sensor Capability

Projects General Guidance
1

Hello everyone,

I am wanting to get some advice on if a project I want to do seems feasible or not. I am wanting to hook up an Arduino to an ultrasonic sensor to detect the presence of a basketball. I'd like the sensor to be at the bottom of the net and pointing upward and have a cone area for detecting the ball. I'm not just interested in the makes, I want to know the misses also thus the reason for the cone area. So far I've tested an ultrasonic sensor and it can pick up a ball just fine. However, when I have the sensor looking up at the hoop it detects other things such as the rim or backboard. I read something about how there may be some sensors that can return all of the analog envelope output, perhaps allowing me to see the presence of a new object. However, I'm struggling to find a ultrasonic sensor that says it outputs something other than the flat distance of one object in the path. Does anyone have any thoughts on how I can detect multiple objects in the sensor path? Perhaps one that I can hook up to Arduino and it just lets me know if there is a large fast moving object in area, and ignore static objects like the hoop?

Please let me know if you think this is feasible or not with an ultrasonic. Thanks for your help.

2

I don't think this is feasible with the cheap sensors you can buy.

In order for it to work at all you will have to build your own system and analyse all the return echoes. Even then you will loose the ball when it is the same distance as the fixed objects like the hoop.

3

I use the little Parallax Doppler radar sensors for motion detection in a home security system. The one sold by Adafruit (I think) puts out a square wave pulse train when motion is detected. Those are quite pricey, so I buy the aw unit for about $4.00, and build my own amplifier/LPF with about 50 cents worth of parts. There is a schematic for an amplifier online. I don't know how you would use it to detect multiple objects, though.

4

Thank you for the replies, I will look into the Parallax Doppler radar. This is quite a tough one so I appreciate any feedback. Also thanks for your honest opinion Mike, I am trying to do this project on a budget so yes would like to avoid a costly system.