New project suggestions, automating a motor to run one a day for a curtain time.

Projects General Guidance
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Hi to anyone who can help.

I am looking to build an automated solution to my marine fish tank so I went into Maplin store in the UK and they me to check out your products. But had no idea how they work or what I would need.

If I can try and explain what I am trying to achieve then if any one can tell me what I would need then I can start to try and locate the information on how to make it work.

I wish to have a motor powered by batteries that can be activated to come on once a day and drive the motor for a set time to allow the motor to rotate enough times to do the job I want. Due being near water I want this system to be as small as possible but i also need the motor to have high torque to drive cloth that's water sodden.

This may seem easy but I have zero knowledge of anything technical so I'm very lost but believe this must be possible , so any help or suggestions on how I could do this would be hugely appreciated.

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This may seem easy but I have zero knowledge of anything technical so I'm very lost but believe this must be possible...

I'm not sure I'd recommend learning microcontrollers, electronics, and programming for a one-time project. It would be a good starter-project if you want to learn this stuff.

Can you handle the mechanics and hooking-up a motor? If you can do that, I'll recommend a few things to simplify the project -

The easiest sketch (Arduino program) is the [u]Blink LED Example[/u]. This is what people normally load & run to make sure the Arduino IDE software is running, everything is connected properly, the Arduino board is running, etc.

The example shows an external LED connected, but if you get a standard Arduino UNO, there is an LED mounted on the board and connected to pin 13. So you can just plug the Arduino into your USB port and get everything set-up without any wiring.

Now, if you can live without a real-time clock (time-of-day clock) and you just need to run the motor for some period of time every 24 hours, you can simply modify the blink sketch for a LOT longer "blink" time, and the software is done!

The delay() function needs to know the number of milliseconds. One millisecond is 1/1000th of a second, and I'll let you calculate how many milliseconds there are in 24 hours. And, you'll have to convert the motor run-time to milliseconds.

The timing won't be as accurate as a clock, but perhaps you can live with a little drift.

If you need to add a real-time clock (and display) that will complicate the electronics (hardware) and the programming (software). But still not too hard, and still a good "starter project" if you want to play with this stuff for a few months.

The Arduno puts-out 5 Volts at 40mA (or less depending on the load resistance/impedance). That's not enough to directly power a motor. The simplest solution is to use a [u]relay[/u]. A relay is an electrically controlled switch. The relay coil (an electromagnet) connects to the Arduino. The coil needs to be rated for exactly 5V, and 40mA or less. The relay contacts are wired in place of a switch. The relay contacts should be rated for the voltage and current of the motor or higher. (Almost any relay will handle a small battery powered motor.)

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DvdDoug , thanks for responding to my plea... Your answer has intrigued me to drive forward with my project I knew there must be a way to make this work.

Regarding the timer that that won't matter how accurate it is as long as the motor turns for the set seconds ever day..

Calculated 86,400,000 ms in a day 24hours so if the motor needs to run for 6 second I would set the delay() at 6,000ms

Before I rush out and buy the parts below, will this software run on a mac/OS I'm not a windows user.

Thanks again for answering I can't imagine what I noob I sounded but this is truly another language to me.

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Having an Arduino running 24 hours a day and driving motors against significant loads might not fit too well with it being battery powered. Have you looked into how big the batteries will need to be and how long they will last?

If you can arrange to have mains electricity available, you can simplify your project by using a domestic timer for the scheduling part. This leaves you just needing to run the motor for a fixed time whenever the Arduino is powered up.

If you can design your motor/drive mechanism so that it runs for a minute or so rather than just a few seconds the problem gets even easier, because it's easy to get a domestic timer with one minute resolution which would take care of the whole problem for you; now all you need is find a motor and matching power supply.