Battery powered servo motor push button

Thread Starter

ikeevens

Joined Nov 23, 2016
17
I know nothing about any of this but curious how difficult and what would needed to create a battery powered 90 degree servo motor with push button to activate. Need it to rotate 90 cw the 90 ccw.

For my project the arm attached to the motor would lay under a paddle and would be used to rotate the paddle back to an up right position after being knocked over and falling on the push button. The weight of the paddle is roughly a half pound.

Thanks for any suggestions.
 

KeithWalker

Joined Jul 10, 2017
2,354
The first step with a project like this is to design the mechanical hardware.
What will you need to locate and lift the paddle and then keep it out of the way so that the paddle can fall again?
How will you ensure that the paddle will always fall on the switch?
Do you really need a R/C type servo to do this or would a linear actuator or geared motor with limit switches make the overall project more cost effective?
Remember; the simpler the solution, the less there is to go wrong.
Give us some details of your progress and let us know when you need help.
 

MisterBill2

Joined Jan 23, 2018
11,888
Very valid and important questions posed in post #2. From the weight of the paddle stated, I am guessing it to be a "table-tennis" paddle, total length about a foot. So if we presume that the rotation will be about the very base of the handle then we have 8 ounces at 6 inches, and 48 inch-ounces of torque required. But we still have no hint about what sort of pivot or hinge the paddle rotates about, nor any words about the surrounding surface, or how fast the paddle needs to move. Also no clue as to what is to keep the paddle in a vertical position until the next time falling event. So there are quite a few questions.
And I am wondering if there is an RC type of servo package even able to provide 48 inch-ounces of torque,
 

Thread Starter

ikeevens

Joined Nov 23, 2016
17
I’ve attached a diagram of what I’ve created.

It’s a knockdown airgun target. Currently using string to pull the reset arm up with a spring attached to the reset arm to pull it back down. I would like the servo motor to replace the string and spring. The paddles are made from EVA form and a hobby stick attached to a hinge and rest against the front panel in the upright position. I would put the push button under one of the paddles which always falls back to the same spot.
I’m trying to replicate this. No sound needed.
https://www.gatewaytoairguns.org/GTA/index.php?topic=143205.msg156272855#msg156272855
kdtd2.png
kdtd1.png
 
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MisterBill2

Joined Jan 23, 2018
11,888
OK, so the target is much different from what I was thinking, and the greatest effort will be at the start of the motion, as the target is flat. So the more efficient lifting mechanism will have it's greatest mechanical advantage at the start of the move, and the greatest velocity towards the end of the move, and then continue moving until it returns to the stowed position. That describes a motor driven gearbox with a crank arm pulling up a "bail" to lift all three targets back into place. The bail pivot would be at the same height as the target pivots, as far back as the sharp bend in the bail side view. The axis of the arm rotation will be parallel to the hinge and bail axis, and far enough above the surface so that the arm will not crash into the surface as it rotates. The link between the arm and the bail must be able to pivot at both ends. The motor/gear train will drive the arm one revolution and then stop. revolution will push the bail far enough up to push the target arms back into place. I have not worked out the rest of the mechanical details yet. Electrically, all targets being down will close a contact to start the motor running, as soon as the arm moves a bit, a contact will be closed by the shaft turning to keep the motor running for the rest of the revolution.
That is about as simple as I can make it.
 

Thread Starter

ikeevens

Joined Nov 23, 2016
17
I appreciate your reply but that has me even more confused.
I saw the video below and thought it may be an easy project but it seems much more complicated. Pull string may be the answer.

 

MisterBill2

Joined Jan 23, 2018
11,888
My solution offered is not complicated, except for my explanation. And that video is exactly why I am so very critical of throwing a processor board at every function. It is so very "Nuts and Volts" that it could have their name on it. And how can needing a processor board with it's power supply and connecting to a packaged RC servo assembly possibly be simple, when it needs a whole lot of code created and loaded to make it do anything at all?? And that system still uses a motor and gearbox and an arm, Small gearboxes are available from a number of suppliers, and many are far more rugged than an all plastic package as shown.
In addition, the video never showed the electrical circuit, only plugging in the pieces that you would buy from them.
Besides that. the system in the video will still need all ofthe hardwareI described to reset the target.
 

MisterBill2

Joined Jan 23, 2018
11,888
The devices in the videos are cute and certainly a bit more entertaining..
Now I have a thought: How about hanging the target from above? It would be obvious when it was hit, and it will reset withno external power except gravity. And you could add a bit of counter weight on top so that it might even spin around once befor resetting. Cheap and easy and no electrical anything, and no string needed. I have even seen some that spin for a while when they are hit. AND it would be very simple to implement with what you already have.
 

shortbus

Joined Sep 30, 2009
9,372
It’s a knockdown airgun target.

The paddles are made from EVA form and a hobby stick
Reading those statements makes me think your "airgun" is actually an "air soft" gun, is that what your talking about here? Or are you meaning a real air gun, or pellet gun?

I can't imagine that EVA foam targets would last long from a real air gun. I have one of these, and it has the targets made from 1/8" thick steel, and works good and saves many steps when shooting my pellet rifles.
https://www.ebay.com/itm/163062071406?hash=item25f741c06e:g:CfsAAOSw94tdeGy-
 

Thread Starter

ikeevens

Joined Nov 23, 2016
17
Reading those statements makes me think your "airgun" is actually an "air soft" gun, is that what your talking about here? Or are you meaning a real air gun, or pellet gun?

I can't imagine that EVA foam targets would last long from a real air gun. I have one of these, and it has the targets made from 1/8" thick steel, and works good and saves many steps when shooting my pellet rifles.
https://www.ebay.com/itm/163062071406?hash=item25f741c06e:g:CfsAAOSw94tdeGy-
No toys real airguns low powered BB guns to high power pcp .25 caliber pellet guns. I have several of the targets you suggested. However, I have a 35 foot shooting rage in my basement so shooting steel is out of the question. The foam last longer than you would think and is inexpensive to replace.
 

Thread Starter

ikeevens

Joined Nov 23, 2016
17
The devices in the videos are cute and certainly a bit more entertaining..
Now I have a thought: How about hanging the target from above? It would be obvious when it was hit, and it will reset withno external power except gravity. And you could add a bit of counter weight on top so that it might even spin around once befor resetting. Cheap and easy and no electrical anything, and no string needed. I have even seen some that spin for a while when they are hit. AND it would be very simple to implement with what you already have.
I think the one attached to the field target is more than cute. Small, compact and heavy duty! I have several of the spinning targets you suggested and all work great. I’ve been airgunning for years and have just about every target imaginable. Just trying to think out side of the box a bit. Again, thanks for all of your suggestions.
 

LesJones

Joined Jan 8, 2017
3,707
I was thinking of the same suggestion the MisterBill2 gave in post #5. I think a windscreen wiper motor could be made to work. It has the cam and contact for it to do one revolution when pulsed past the contact open position.

Les.
 

Thread Starter

ikeevens

Joined Nov 23, 2016
17
I was thinking of the same suggestion the MisterBill2 gave in post #5. I think a windscreen wiper motor could be made to work. It has the cam and contact for it to do one revolution when pulsed past the contact open position.

Les.
Maybe, although, the wiper blade motor may be a bit big. It looks that the motor on the field target reset seems like it would be much smaller.
1645656030861.jpeg
 

LesJones

Joined Jan 8, 2017
3,707
The suggestion was to avoid having to build something. You could build a device using a geared motor with a disk and a crank mounted on it's shaft. The disk would have a notch on it's edge and a micro switch would be positioned so it was activated when it's roller was against the edge of the disk but when the notch was positioned at the position of the micro switch roller it would not be operated. The micro switch contacts that were open when the notch was in line with the micro switch roller would be connected in series with the motor. This would make the motor rotate until the notch was in line with the roller. A push button would be connected in parallel with the contacts on the micro switch. When the push button was pressed for a moment the notch would move away from the roller. The motor would then continue to rotate until the notch lined up with the roller on the micro switch.
This is what MisterBill2 was describing in post #5.

Les.
 
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