Collecting accelerometer data for analysis

Unity Engine
,
1

Hi - I want to collect a bunch of data from the iPhone accelerometer for analysis back on my desktop machine.

Is there a simple way for a Unity application to collect and transfer that kind of information back to my machine?

I am thinking that writing to a file would be the easiest way, but cant find any file writing APIs.

2

File writing can be found in the dot net System.IO classes.

Transferring back to your desktop machine will be the tricky part. You might want to use a web server with HTTP file upload as the middleman. Though if you’re doing this as a one-off, you can probably hard code your desktop’s IP address and open a listening socket on some random high port, and have the Unity app send to that.

3

I don’t really want to set up a webserver for this

Any other ways of doing it? How do I get a file off the iPhone?

4

Unless you jailbreak the phone, there’s no easy way to get a file off it.

If you’re doing this as a one-off (i.e. an experiment you are doing, not as part of a game you are distributing) just run a socket server on your desktop PC, and send the data over a socket to it.

You can make a simple socket server using tools you probably have around the house. Perl makes it pretty easily (IO:Socket makes it easy, see here: http://www.perlfect.com/articles/sockets.shtml or here: http://perl.active-venture.com/pod/perlipc-tcpserver.html for a socket server in under 20 lines).

In your Unity app, connect to that socket server using the System.Net.Sockets.Socket. A sample of that is here: System.Net.Sockets.Socket Class

However, if you jailbreak the phone, you can use the “Disk for iPhone” FUSE module to mount your iPhone to the desktop as a USB file device, and browse to your app’s /Documents directory, and copy the file from there.

5

For those without the pro version of Unity, heres a basic webserver:

            HttpListener listener = new HttpListener();
            listener.Prefixes.Add("http://*:8080/");

            listener.Start();
            Console.WriteLine("Listening...");

            byte[] ok = System.Text.Encoding.UTF8.GetBytes("OK");

            while (true)
            {
                HttpListenerContext context = listener.GetContext();

                Console.WriteLine(context.Request.Url);

                byte[] buf = new byte[1024];
                MemoryStream ms = new MemoryStream();

                int len = context.Request.InputStream.Read(buf, 0, buf.Length);
                while (len > 0)
                {
                    ms.Write(buf, 0, len);
                    len = context.Request.InputStream.Read(buf, 0, buf.Length);
                }

                buf = ms.ToArray();

                Console.WriteLine(System.Text.Encoding.ASCII.GetString(buf, 0, buf.Length));

                context.Response.StatusCode = 200;
                context.Response.OutputStream.Write(ok, 0, 2);
                context.Response.Close();
            }
            listener.Stop();

Use WWWForm and WWW to submit to the server.

I am running the code above from Visual Studio, but it should also work under Mono