# popping actuator

Discussion in 'Sensors and Actuators' started by qfire320, Jul 29, 2014.

1. ### qfire320

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Jul 29, 2014
I am looking for a linear actuator that will give me a quick pop type motion to pop a tennis ball up about 4 foot

can any one point me in the right direction

2. ### (*steve*)¡sǝpodᴉʇuɐ ǝɥʇ ɹɐǝɥdModerator

25,497
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Jan 21, 2010
A solenoid perhaps?

3. ### qfire320

3
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Jul 29, 2014
Yes where.can I find one that would operate in a pop type motion?

4. ### (*steve*)¡sǝpodᴉʇuɐ ǝɥʇ ɹɐǝɥdModerator

25,497
2,839
Jan 21, 2010
A push type solenoid will (if it operates with sufficient force) accelerate the ball. Whether it does it enough to make it jump a metre or more in the air would be determined by the speed of operation of the solenoid, and its throw.

If the solenoid has sufficient power, bit insufficient speed or throw, then perhaps it can operate a lever with the ball placed further from the fulcrum than the solenoid. This will work with either a push or a pull type solenoid.

5. ### KrisBlueNZSadly passed away in 2015

8,393
1,271
Nov 28, 2011
Try Google. You have the magic keyword, "solenoid". Also, try electronic component e-tailers and robotics component e-tailers.

6. ### Terry Gould

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Jul 31, 2014
If full automation is not required you could get a solenoid strong enough just to hold a spring compressed. Then it doesn't matter how fast the solenoid is, it'll be the spring popping the ball.

7. ### JimW

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Oct 22, 2010
IMHO, you are going to have trouble doing this with a solenoid. Too much energy to transfer to make a standard tennis ball jump 4 feet straight up. With a big enough electromagnetic coil, big enough low-ESR capacitor bank and the right circuitry, you might get it to go. I think you would be sourcing some pretty expensive items and it still would be marginal to succeed.

I have a simple one built that pops a 1.5" diameter toy ball up a few feet. It is an old loud speaker (8" or so) that has a large pulse driving the coil. Slow charge to a high energy capacitor bank that is driven as a shaped pulse into the loudspeaker coil. Small ball and low height, and not really a linear actuator.

If the requirement for a linear actuator is flexible, I would think a better approach would be a motor spinning around an arm that hits the ball upwards. A single spin and use the energy of the arm to pop the ball upwards.

Otherwise, I like Terry's idea of compressing a spring and letting it explode out of compression to generate the energy to pup the ball up. But I think a geared motor to compress the spring.

Jim

8. ### BobK

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1,688
Jan 5, 2010
If it doesn't have to repeat more than once every several seconds, I think a good approach would be to use a gear motor to compress a spring, then a solenoid to release it for a nice pop.

Bob

9. ### shumifan50

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Jan 16, 2014
Just a thought: how about the solenoid off the starter of a car. They are quite powerful, engage rapidly and run off 12V and could be had quite cheaply from a breaker yard. They already have a pivot point to add a lever to amplify the acceleration of the motion.

10. ### qfire320

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Jul 29, 2014

Yes I have thought of this gonna go pick one up tomorrow I hope

11. ### shumifan50

578
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Jan 16, 2014
Just bear in mind these draw quite a bit of current, so you will need a substantial battery and a switch that can handle the current - most likely best to use a relay.