1st project- design to turn a key, ard. linear actuator, via wireless remote

Hello all :),

I want to take on a remote electronic/robotics project. I am a noob. I have a generator that needs to be turned on (by key only) it feels a lot like an ignition key in a vehicle. The generator is in a safe/secure screened in housing garage structure, free from rain. The floor is cement so I will need to have this module stationary some how maybe just by weight alone.
I would like to build something to simulate a hand turning that key. About 90degrees release it retract and reset to do it all over again. It needs to work just like you would do it if you were present. And I would like this to be wireless remote for at least 2000 feet. Of course I want the remote switch on my person and be as small as possible (given the range needed for it to work)
Due to it having a moving turning motion I would want it to move the module away from it instead of actually turning the key.

As for power, I guess one pound of pressure/torque… I would prefer to use batteries just because I dont like cords, or having to go all the way down there to turn it on etc.

When it shuts off - does that automatically. It has a timer shut off

I would like a long range key turner. I don’t know of such a device I can buy to accomplish this. I figure I will just make one.

I live next to a big city and am concerned of RF interference - it getting switched on by accident. That would be bad, especially if I was not at home AND un aware…

I think this is possible.
I appreciate all suggestions and direction.

Actions is simple -
I hit a button on a remote, and that sends signal to turn the key.

2 small fixed bars that can slide up to each side of the key
once bars are surrounding the key, wrist motion of 90 degree hold for a second
90 degrees of motion (maybe 100 just to be) I will need a hard stop somewhere though.
And then retract and re-position for next start. Maybe use arduino linear actuator?
I don’t need an entire prefab arm with elbows, or tilt…(Also worth mentioning, I cannot open, rewire or alter the generator, this has to be created externally.) That’s why I am building this myself. My budget for this is $600.
So is this practical? Do-able right?

Thank you,
Charles

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Why can't the device be in contact with the key all that time? That would greatly simplify the mechanicals.

Is it not possible to use relays to complete the electrical circuits that the key closes?

Is it wise to automate this process - from a safety point of view? For example what if someone you could not see was touching the machine when you press the remote start? Or if some debris had fallen into the mechanism?

...R

An ignition switch usually only gives power to a few different spots. Usually first click is accessories ( just like a car) and second is ithe starter relay. You could bypass the mechanical portion that you are trying to build .

Is there a reason you want to build the physical mechanical key turning device. Is the generator a backup generator. With the arduino you don't even need wifi. You could have it monitor electricity with an amp probe or some other device and if it looses
That signal it could go through a start sequence automatically.

This could control 8 relays although you only need two.

Not trying to change your idea just food for thought.

Lol. Sorry I just now saw your relay idea but we are on the same page.

I agree with Reply#1. If you really do end up needing to physically turn the key, the most natural way to implement that IMO would be to use a suitably rated RC model servo. There are umpteen ways to control it remotely but the 2000' requirement limits your options. Unless you're willing to stump up for a mobile data connection you'll need to use a local radio solution. I haven't used them myself, but Ciseco do some Arduino compatible RF products and for the high powered transceivers they're talking of ranges up to tens of kilometers under ideal conditions. Obviously you can't count on ideal conditions but it seems likely to be enough for what you need.

1st reply Robin2

I suppose it could stay in contact. But just as an ignition of a vehicle, you know how you have to release it after it cranks? - It has to reset position so not to cause problems mechanically.
That's why I was thinking we need to retract.. So it can get away from it. I mean it could flow back for a 10th of a turn, its just that timing would be crucial. To test this once its built, I will have to tweak it and feel it out, if it feels the same. This will be a learning project for sure.

If you are talking about relays to change my wiring? No that cannot be opened or tampered with.

This is stored in a sheltered, steel cage, with screen, nothing is going in or out of this room. And no one but me has access. Nothing can interfere with it, under any other circumstance I would say no its not wise. But under the conditions I have, I cant see why not.

2nd reply Styler93gsx

I cannot alter the generator internally, too much to go through on that. Warranty, We have guys that maintain them.
I want to build the physical mechanical part for lots of reasons. I want the experience first and foremost. I feel to be the geek I want to be I need to make this!
It will save me time and effort of other things.
Its cool.
I would like to use this mechanism for other manual things, maybe Halloween prank, or maybe to pour a cold beer on an expansion mechanics that I get in to down the road.
This is something my son and I can learn and work on.
I dont know where to start, but this might as well be as good as any.

This is not a backup generator.
If this can control 8 relays, cool, I may expand one day in the future, maybe for a different
project altogether.

Reply 3 PeterH
Yes, this is a must build :slight_smile: - Physical turn! Remote style!
RC Model servo - Can that handle a pound of torque?

I thought of the mobile data plan.. its not really that important, I think i can work around distance to avoid data plan.

All of your Input is a great start..
Thank you folks! I will google all of this over the weekend here, and repost by Monday..

I was also thinking of using a servo. Some of them are very powerful and I imagine you could get one that could turn an ignition key. Look up (for example) the HobbyKing website.

I don't think the business of retracting the device from the key is logically any different from having a servo rotate "backwards" to release the key from the start position.

In either case how will you know that the engine has started?

Sometimes an engine starts within one turn of the crankshaft and at other times it may need a few revolutions. Then there are cases where it seems to start but then comes to a stop and needs to be started a second or third time.

Does the starter system have a clutch so that no harm arises if the starter remains engaged after the engine starts? Is there a limit to how long it is safe to have it in that condition?

Are there conditions to test before knowing the key can be turned without damage to the engine?

The human brain deals with all these situations and many more effortlessly and subconsciously. Software won't unless it is programmed for EVERY possibility.

...R

Actually it is just like this - YouTube

The only difference is - my turn range is exactly 90 degrees. Once turned the hold duration is 1 second.
So I am thinking 1 pound of torque to be on the safe side.
I think you are right on the 'no need for retracting as long as it can reverse/go backwards to medium running state.'
And I think I dont even need a grip claw if I can get it seated in the right position and its just going to stay in place.
After a while (hours) I will go back to the generator, and manually pull the device away from it, and shut it down manually. Once there I dont need a shut down process.

All of these servos is very overwhelming.
Hobby King is a nice layout of a site - for sure.

By the sounds of your writing and this is only and assumption (please don't take this the wrong way) A switch (ignition switch) or relay do the exact same thing. They make an wire that connect to another wire. One uses a physical key and the other can use a pin from an Arduino. And by all means you can change the time period for how long the key (relay) is turned to the start position. Its as easy as blinking an LED. After you get the led to blink only (1 number has to be changed to adjust the cranking time)

const int ignition = 2;     // just like turning the key but with using a button
const int ignitionSwitch =  13;      // the wire that starts the motor(connects to relay(to high of amp for arduino)

// variables will change:
int ignition = 0;         // variable for reading the pushbutton status(ignition switch)

void setup() {
  // initialize the ignitionSwitch pin as an output this goes to starter
  pinMode(ignitionSwitch, OUTPUT);      
  // initialize the pushbutton pin as an input this comes from the battery, through the switch (virtual switch)
  pinMode(ignition, INPUT);     
}

void loop(){
  // read the state of the pushbutton value:
  ignition = digitalRead(buttonPin);

  // check if the pushbutton is pressed.
  // if it is, the buttonState is HIGH:
  if (ignition == HIGH) {     
    // turn LED on:    
    digitalWrite(ignitionSwitch, HIGH);  
  } 
  else {
    // turn LED off:
    digitalWrite(ignition, LOW); 
  }
}

Robin2:
I was also thinking of using a servo. Some of them are very powerful and I imagine you could get one that could turn an ignition key. Look up (for example) the HobbyKing website.

I don't think the business of retracting the device from the key is logically any different from having a servo rotate "backwards" to release the key from the start position.

In either case how will you know that the engine has started?

Sometimes an engine starts within one turn of the crankshaft and at other times it may need a few revolutions. Then there are cases where it seems to start but then comes to a stop and needs to be started a second or third time.

Does the starter system have a clutch so that no harm arises if the starter remains engaged after the engine starts? Is there a limit to how long it is safe to have it in that condition?

Are there conditions to test before knowing the key can be turned without damage to the engine?

The human brain deals with all these situations and many more effortlessly and subconsciously. Software won't unless it is programmed for EVERY possibility.

...R

If you microcontroller had a sensor added to measure amperage or senso RPM (maybe some sort of hall sensor) added it would know it was running. If it wasn't running you could put it through another start sequence). If motors are in good running condition then the starting conditions are usually pretty reliable. As far as starter being engaged yes, the starter has whats called a Bendix gear. This gear engages the flywheel during starting and pulls off afterwards. If your your motor usually starts withing 3 seconds your can write a program to turn the motor for 3.5. Do some testing heck you could add a servo for a choke and add an engine temperature sensor to either have it engaged or not engaged.

Have fun.

Interrupts are killing me right now. Its like your problem of starting a motor but I'm trying to count the rotations of a motor spinning 20-30k rpm and have it stop at a specific count.

styler93gsx:
As far as starter being engaged yes, the starter has whats called a Bendix gear. This gear engages the flywheel during starting and pulls off afterwards.

I didn't write my comment because I did not know how starter motors work. I wrote my comment because I don't know whether the motor being used by @crown808 might be damaged if the starter motor is not disengaged immediately the engine fires.

I stil don't know. And my comment remains relevant.

...R

It won't hurt the starter to stay engaged for second or so after the motor has started running.

styler93gsx:
It won't hurt the starter to stay engaged for second or so after the motor has started running.

Is it definitely an inertia reel starter rather than a solenoid starter? If it's using a solenoid, you'd need to be concerned about overspeeding the motor.

styler93gsx:
It won't hurt the starter to stay engaged for second or so after the motor has started running.

And how do you know when, exactly, it starts running?

...R

It is solenoid and it takes 1 second then I would release it, It then goes to a middle position (from the initial 90 degree twist)
This is the state it remains while running.
From Here, I would let it run and then manually turn it off. Turning off is no bigdeal, I can stop by on my way home or on my way out.. either way. I just need the start portion to be covered. I can remove our device and manually take over.

Run position is the position where the key sits while running. Start position is the position it sits when the starter is engaged. I've been a master mechanic since I was 21 and building motor since I was 8 years old. The bendix gear is just a gear that is on a shaft that is dis engaged by a spring. If you don't believe me go out and try to start your generator and after it starts hold it for a second or two longer after the motor has fired. after the flywheel starts turning faster that the bendix the gear pulls back. Its kind of like a one way bearing. So long as you don't trying to re engage the gear when the flywheel is turning it won't make the grinding sound. If you stay with it everything sounds smooth. Thats the one way bearing. But if you try to start it while the motor is already running or the motor is winding down you get a crunch noise. You won't get the crunch noise if you stay with it because the bendix is already up to speed. Its when you try and start, stop, let off and try to re start that you get the crunch sound.

crown808:
It is solenoid and it takes 1 second then I would release it,

How will you deal with the situation when it needs 5 or 10secs of starter before it fires?

Of course one way is just to be content that it won't start on that day.

...R

A previous response already suggested that you sense the current and/or voltage from the generator to detect a failed start. If it didn't start, you'll know it didn't start and can reattempt X number of times.