Hi guys, I need to know what I need to achieve a small project. I need to activate a stepper motor by a push of a button from a RC Remote, the stepper motor needs to move for example like a clock, push button it moves to 1, push button and moves to 2 and so on. I probably could go arduino but that might be overkill for that task.
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A step/direction stepper motor controller will do this with a push button interface. Hardwire the Direction input to the direction you want the stepper to turn, and then use a momentary push button switch to pulse the Step input and the motor will step once. The switch will likely need some debounce circuitry to ensure only one pulse per press.
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Hi Michael,
Welcome to the forum!
Depending on the remote that you have you might need a microcontroller as a middle man to interpret the signal. Do you have a picture or link to the device you are using?
Making sure it returns to the same spot is a bit harder - you’d be after some closed-loop type of control.
Still very achievable though!
Hi Jeff,
That is such an elegant solution, a simple button driving a stepper.
Liam
This is an example of the type of device that could be used to provide that button-press for the controller:
rcd3003.pdf (flashrc.com)
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My remote will deliver a standard PWM signal so to convert that do I need a arduino or can a standard motor controller do it?
An Arduino can be programmed to detect a PWM signal, but a device like the one I referenced above is a better option. Here is another example:
That delivers an on/off signal rather than a pulse, but there are ways to handle that.
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Hi Michael
What is a “standard” PWM signal ?/
Cheers Bob
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So I just go from my signal wires to your rc switch - arduino - stepper driver or bridge - stepper motor. Then learn how to code it, is that pretty much it?
My suggestion is that you don’t use the Arduino at all.
The devices I linked are designed to plug into a spare channel of the RC receiver unit. I assume that your RC controller has a button that you will use. This button should be linked to a channel in the transmitter (probably configurable) and there will be a corresponding channel in the receiver. That’s where you plug one of those devices. Then, when you press the button on the remote the device responds according to its type - a pulse on one output for that first item, and an on or off for that second item.
The advantage of that first one is that it is specifically designed to provide a single pulse, so it doesn’t matter whether that is created by a button or a slider on the transmitter, and switch bounce problems are unlikely. The disadvantage is that it cycles through multiple outputs. The advantage of the second one is that the controller can control the on/off sequence, but that might be clumsy to operate if the controller only has a slide or joystick available for the spare channel. Also switch bounce might be a problem, although it does have +/- 64us of hysteresis. If neither of these is suitable then there are probably other devices available that might suit better. You could search on “RC PWM Switch” or similar.
The output of whatever device you choose is then connected directly to the Step input of the stepper controller.
When you press the button on the RC controller a PWM signal is sent to the receiver on the channel assigned to that button. It is received at the receiver and directed to the receiver output for that channel. That output activates the device connected to that channel, then either (1) the pulse is sent to the stepper controller to step the motor, or (2) the signal is turned on then turned off when you release the button, which should also function as a pulse for the stepper controller. No Arduino and no programming is needed.
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If I don’t use a controller like arduino how can I tell the stepper motor to move a set distance it won’t necessarily be a single step. It would be around 36 degrees at each button press. Sorry if I sound stupid, electronics is nit my thing.
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You can’t. I assumed that 1 meant 1 step and 2 meant 2 step, like a clock. If the distance of each step is not one step of the stepper then you will need something to control the number of steps, and an Arduino (eg, Nano) would be one way to do that. You can choose to use a device like I mentioned to trigger the Arduino (in which case the CORE product would be preferable) or do the PWM decoding with code. Which option you choose might be dictated by space and power options, but you could start by trying the code route and see if you can do reliable decoding, and go the hardware route if that fails.
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Hi All
Firstly I have a feeling this is an extension of another post involving the fitting of a similar device to a Drone. Might be wrong but I have a suspicious nature. No matter.
Here is a little circuit you could try. Does not use any Arduino or stepper. Just a geared brushed DC motor. If you did not want gears slow it down some other way like a belt drive or something.
I am assuming you wish to rotate a disk. Cut some slots or drill holes around the edge of the disk and arrange to mount a photo interruptor (Jaycar ZD1901 or similar) so the disk passes through the aperture.
This works on a characteristic of Mosfets that they will remain ON until the Gate capacitor is discharged (even when power is removed). So once turned ON it will remain ON until the disk gets to a slot and the interrupter discharges this cap and turns it OFF. When the Mosfet is pulsed ON again the process repeats. The only proviso here is the ON pulse must be long enough for the disk to move the hole past the interrupter.
There is a possibility you may have a problem with over run. That is why I suggest gearing down in some way. I think the higher the gear ratio the less likely over run will be a problem. I think this depends on too many factors and only experiment will be the deciding factor. If over run is a problem we will have to devise a way to stop the motor pretty much instantly.
Cheers Bob
PS I haven’t tried or tested this circuit but I don’t see why it would not work.
If a Hall Effect switch would suit your purpose better this could replace the photo interrupter and would still operate the same.
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