Make:

Ah, the joys of applied robotics. Quite an intelligent dog there.

Version 2.0 should have a randomizer to add some challenge, looks like Jerry has mastered that one already.

This is one cool dog !

Obviously my human does not love me, because I do not have one of these. When she gets home from work I will eat her cell phone again, in retaliation.

every time the dog put the ball in the launcher, then had second thoughts, I winced, thinking about it getting its ear ran over by the sling roller or getting a paw smooshed by the machine, and with the little kid started playing with it too UGGH! It scared me, its a nice machine, but I prefer to throw it myself and avoid the risk of hurting someone, and instead hurt windows and other breakable objects :)

The robot looks like it has a few safety interlocks and sensors, though probably a few places a finger or paw could get pinched or slapped. Maybe it has additional cowling by now. Regardless, it was both the coolest and cutest thing I've seen for a while.

I don't want to alarm anyone, but I think something happened to Jerry the dog in the second to last scene of the video. He looks like he had some kind of altercation with the ball thrower, perhaps over degree or velocity of pitch.

I think this is overly complex. I can think of doing this with a simple microcontoller, a car air compressor, 2 relays, some pvc, a switch, a pressure sensor (hell, even a switch hacked onto a pressure gauge), and two solenoids. Pneumonic ball (potatoe) cannon, so no moving parts.

The air compressor is connected to a relay, so a micro controller can turn it on. It is also connected to a 12v solenoid. Both of these are connected to the same relay (When the Compressor is on, the solenoid is open. When off, the solenoid is closed.) The other side of the solenoid is the ammo reservoir made of pvc. Connected to this is a pressure gauge that somehow connects to the Microcontroller. This reservoir is filled to a predetermined psi. The other side is another 12v solenoid. This is the trigger solenoid (Normally held open). When triggered, it allows the compressed air to escape, launching the ball. The cannon/muzzle is another pvc pipe. Inside this pipe is a push button switch and a stopping wall.

Connected to the micro-controller is the two relays, a pressure gauge, and the trigger push button switch. When the push button switch is closed, the micro-controller closes the trigger solenoid (it is left open as a safety measure) and enables the first relay, thereby opening the first solenoid and turning on the compressor. The compressor fills the reservoir to a predetermined psi, which triggers the pressure gauge and signals the microcontroller to turn off the first relay, closing the solenoid and turning off the compressor. The trigger solenoid is then opened, launching the ball.

Depending on the compressor (if it has a builtin gauge and if it has a way to prevent pressure from leaving backwards when turned off) the first solenoid and the separate pressure gauge is not needed.

Hell, I can even think of a way to do this without a micro-controller, with just some complicated switch placement.

Way too complicated... How about a simple wheel spinning inside of a toriodal chamber? The ball would be fed through a funnel, to fall between the spinning wheel and the inside of the toroid, and launched.

Obviously the person in this video wanted a robotic solution. Mine would be too simple.

Cool. The proper use of technology is to make people and other small animals happy. Jerry is obviously very happy with his toy.

Of course it is too complicated. The simple answer is to throw the ball. The dog is happy, the kid loves it too. I don't know what this is but it I think it has the heart and soul of what Make guys are going for.

From elsewhere:

"I built the ball machine because I thought my dog Jerry, might like it and that it would be something fun for me to build. So after two years of on and off work, with many safety features such as IR proximity sensors to protect Jerry and my son from the machine, I finally complete."

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