Parts Needed for Event Recorder

Projects General Guidance
1

Hi,

Like the previous poster, I think I can figure out the programming aspect, though I'm completely 100% new to hardware. I want to build something that sounds simple - would you guys help me pick out the hardware?

I want to build an event recorder like this:

  • I press a button, and it logs the current date & time
  • It can store many such events at once (say, 1000)
  • It has a battery and doesn't need to stay connected to the computer, can be carried around
  • The time is sent either wirelessly by internet to a server when it's in range of a wireless signal it knows (ideal) or, alternatively, by connecting to a computer (okay for now if this is much easier)
  • The whole thing is as small as possible

If it's not much more complex, I'd like to do this with 7 buttons (recording 7 different events).

What parts do I need here? Thank you! :slight_smile:

2

What parts do I need here?

I think you've figured that out, haven't you.

  • I press a button

Then, you need something to press. I'd suggest a switch, rather than a button. You press my buttons and I get upset.

and it logs the current date & time

Then, you need an it (whatever that is, presumably an Arduino) and some way to know the current date and time (an RTC is good).

  • It can store many such events at once (say, 1000)

There is not enough EEPROM to store that much data, so an SD card reader/writer would be needed.

  • It has a battery

Then you need a battery.

and doesn't need to stay connected to the computer, can be carried around

OK.

  • The time is sent either wirelessly by internet to a server when it's in range of a wireless signal it knows

This requires some complex programming and some expensive hardware. Oops, there goes your battery life.

or, alternatively, by connecting to a computer (okay for now if this is much easier)

Simply remove the SD card and plug it into the computer. What you do with the data on the PC is up to you.

  • The whole thing is as small as possible

An Arduino, SD reader, and battery pack can be relatively small. When you get a module doing what you want, you can build your own PCB board with just the AtMega chip, crystal, caps, regulators, and SD reader. But, that's a ways down the road.

If it's not much more complex, I'd like to do this with 7 buttons (recording 7 different events).

6 extra switches; very little extra code.

3

All of these are within the power of Arduino. I suspect before worrying about it being as small as possible, get it to work. Then once you have it working, get it small.

As others have said, you want a SD or micro-SD card to record the results, and a real-time clock to know about the time and date. It may make sense to find a shield that combines some of the features, rather than adding them piecemeal, such as this Adafruit data logger shield with SD card, real time clock, light and temperture sensors: Light and temperature data-logger pack : ID 249 : $27.50 : Adafruit Industries, Unique & fun DIY electronics and kits. You will need to be able to solder to use this, and you would need to buy an Arduino, such as an Uno as well. You would just add some buttons. If you want seven buttons, it may make sense to use a rotary encoder (switch that gives a different value based on how you rotate it) to select which event to record, and then a button to record the information other than firing. Initially, communicating the results via wifi or bluetooth, will add to the complication. I would say do it first without the network, using the SD card to move the data, and then move it to the computer physically. Over time you can add the bells and whistles, and if you need to get it smaller, you can move it to a custom chip.

However that being said, if you are not looking to learn by building the recorder, and you just want to record the data, if you are carrying a smart phone around (apple or android), I would say just use the phone to record the data. You would need to look around the respective app stores for some app that allows you to push a button on screen, and have it record data/time, and then syncs up with the network.

[edit]
BTW, when I was scanning the other forums, I noticed this logger that was first announced in April, but somebody had a question about it today: http://arduino.cc/forum/index.php/topic,100539.0.html.

4

Thanks, Paul & Michael! :slight_smile:

5

You could also write an app for a smart phone that does all the things you enumerated. (Draw the 7 buttons on the touch screen.)