# I want to build an automatic button pusher

#### mauricev

Joined Feb 18, 2007
3
I have a Homestar Pro planetarium (see http://www.audiocubes.com/product/Segatoys_HomeStar_Pro_21st_Century_Home_Planetarium.html), which is a cool device. To make the device go, after it is plugged in, the unit must be turned on by sliding the power switch to the left and also pressing the "move" button. After 3 hours, the unit stops moving and displaying stars. At that point, the powering sequence must be re-executed. Of course, I'd like to have the unit to run continuously. Unplugging and replugging the power cord does not bypass the powering sequence. It must be done manually each time.

The unit also has separate timer buttons for 15, 30, and 60 minutes. It appears that pressing these buttons while the unit is timing down resets the timer. So I think what I'm looking to do is to make a gizmo that automatically press the timer button at least every 14 minutes. (It might even be possible to press another button such as the moving stars button once every 179 minutes to reset the timer. I'm not certain about that.)

So the question is what can I do to build an "automatic button pusher"? I found a circuit diagram online that might do the job, which is attached to this post.

The first question is whether I'm missing something simpler than this. It seems to hard to believe that in the entire world of hobby robotics, that there not automatic button pushers all over the place.

If indeed there are not, then could this circuit do the job? For one thing, it's not clear to me whether a solenoid is capable of pushing and then letting go automatically (pulling back) or whether that has to be be programmed into the circuit.

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#### hgmjr

Joined Jan 28, 2005
9,029
The picture in the link you provided lacks detail so I have a couple of questions.

Where are these pushbuttons located? Are they on the Planetarium sphere or on the power supply?

hgmjr

#### mauricev

Joined Feb 18, 2007
3
The picture is not mine. It is just a schematic of someone's circuit that I found on the Internet appears that it can be used to push buttons using a solenoid.
The buttons are on the planetarium itself. If you look closely at the planetarium picture in the first link, you'll see the row of buttons. The one I want to push is round, about 3 mm wide. I would have to somehow mount the solenoid to something to match up to where one of the buttons and secure both, so the force doesn't push them apart.

I'm attaching a better picture of the planetarium, showing the buttons more clearly.

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#### beenthere

Joined Apr 20, 2004
15,819
In order to avoid the inconvience of mounting a soleniod which will interfere with the normal use of the keypad, why not use a relay in parallel with the pushbutton switch to make the closure every several minutes? You'll have to do some disassembly for this, but the solution is more elegant.

#### hgmjr

Joined Jan 28, 2005
9,029
Maybe before you get too involved in a significant effort to work around the timeout limitation, you may want to contact the device's manufacturer and see if there is some way to put the device into a continuous operation.

hgmjr

#### mauricev

Joined Feb 18, 2007
3
There is not; the company even warned me the warranty is void once I start messing with the insides.

So then, the relay sounds like a good idea. So if I understand it right, if I put a wire for a really short time across the two terminals of one of the buttons, then that should have the same effect as pressing the button. Does the gauge of the wire matter? The unit has a 12 V DC input.

If that works, my next step would be to see if wiring up a relay to the two terminals would do the same thing.

Then connect the relay to a timer circuit. It seems there might some relay+timer kits out there might fulfill that role.

#### BazsoDombiAndras

Joined Apr 26, 2015
65
I'm looking for the same kind of button pusher.

There is a commercially available device name Microbot Push, but it costs 49$(+99$ for a control center if you wish to control it over Wifi). See here: https://prota.info/

I'd rather make something at home, though, Microbot Push is nice and elegant, but just too expensive, especially if you need more than just a few...

#### TheButtonThief

Joined Feb 26, 2011
237
It seems to hard to believe that in the entire world of hobby robotics, that there not automatic button pushers all over the place.
This is because such a product would have to be bespoke to a specific need and a specific button on a specific appliance. There are just too many environmental and ergonomic variables to consider when attempting to design such a thing.

There is not; the company even warned me the warranty is void once I start messing with the insides.
You may as well face it, if you want someone else's product to function in a manner which it wasn't designed too, you're going to have to modify it, the warranty is something you're just going to have to sacrifice if you want the added functionality.

To take the "button Pusher" approach, you're going to have to figure out a way to mechanically hold the solenoid above the button without interfering with the device's functions and without tampering with the hardware (you now see why there isn't any universal button pushers on the market) all for the sake of not voiding the precious warranty.

A far simpler approach would be to open the appliance, locate the terminals on the push switch and solder in some little wires, connect the other end of those wires to the NO contacts of a relay and either build or buy a timing circuit to control the relay. Take a look at this Velleman kit if you'd prefer the modular approach.

#### BazsoDombiAndras

Joined Apr 26, 2015
65
You may as well face it, if you want someone else's product to function in a manner which it wasn't designed too, you're going to have to modify it, the warranty is something you're just going to have to sacrifice if you want the added functionality.
That's exactly what needs to be avoided. We're talking here about appliances worth many hundreds of dollars, so loosing the warranty is not an option. A mechanical button pusher is the solution, even if it's hard to make.

#### TheButtonThief

Joined Feb 26, 2011
237
That's exactly what needs to be avoided. We're talking here about appliances worth many hundreds of dollars, so loosing the warranty is not an option.
Then you have to ask yourself; what's worth more, the warranty or the added functionality?

If the warranty is so valuable to you, maybe should have went with a product that already does what you want. If such a thing doesn't exist, either make your own or buy the closest match to your needs and modify it. This is what our species has been doing for thousands of years.

#### BazsoDombiAndras

Joined Apr 26, 2015
65
That's nice in theory but does not work in practice...

Take my case for example. I have an air purifier device which is one of the best out there. I can't replicate an air purifier, I'm no hardware designer, producer and I have no knowledge in that field whatsoever. So all I can do is buy a good air purifier. There are lots and lots of reasons why I chose this exact model, so I don't want another one instead just because I can't remote-control it.

However, I want to turn on the air purifier remotely (and automatically) whenever my solar panels are producing excess energy, so that I can utilize that energy for a useful purpose instead of letting it go to waste (it's an off-grid system). But I can't turn on the air purifier remotely and automatically. that's not because it doesn't have this feature. I could get around that with a remote controlled wall plug. The problem is that the air purifier doesn't remember its last state after a power cut, so when I turn the wall plug back on, the air purifier does not turn on again. I need to somehow remote-push its on/off button.

Needless to mention that the purifier cost me a ton of money and that I have 2 years of warranty left... so that leaves me with a single choice: a remote controlled mechanical button pusher. And there are many cases out there with people who have very similar use cases and need very similar solutions. I agree with our friend mauricev (the original poster), it's unbelievable that there are so very few commercial solutions available for this (I only know one: the Microbot Push). Yes, the buttons are very varied and generic solutions won't be able to push all possible buttons, but I'm sure you can make a generic button pusher which would be able to handle at least 80-90% of the buttons that exist in practice. most devices sold today have simple push switches or toggle switches...

#### shortbus

Joined Sep 30, 2009
8,691
Is it possible to "tape the button down"? Keeping it on permanently and then use the remote control wall plug to turn the power on and off.

#### BazsoDombiAndras

Joined Apr 26, 2015
65
I did think of that But it starts on speed 1 and I need at least speed 4, so after tapping the power button I still need to tap the speed button at least 3 times. The relay suggestion is very simple and elegant, but unfortunately it requires disassembling the unit, so I'd rather go with a mechanical solution. Thanks!

#### GopherT

Joined Nov 23, 2012
8,012

#### BazsoDombiAndras

Joined Apr 26, 2015
65
Yeah, I've seen it... there's even an Instructables tutorial for it... but I don't need a timer-based solution, rather a WiFi-connected solution to automate it. And this one in the video is too bulky...

#### Externet

Joined Nov 29, 2005
1,625
Ask the manufacturer service center if they can modify it to your wishes. Cannot be a difficult thing when they know its circuitry, and ask to include a technician handwritten note inside the unit for warranty purposes.

#### GopherT

Joined Nov 23, 2012
8,012
I need one of these - it can automatically undo the changes that my neighbor, Bob, tries to make to the audio system every time we have a neighborhood party.