Running Diary - Entry 3

20 minutes of 40 seconds run, 80 seconds walk. Was fine, and so was Amy. In fact, I found it a bit easy, so I did an extra sprint at the end.
What I mostly wanted to write about though was iterative design.
Before the first session, I wrote a little program for my phone. Basically, it allowed you to enter two numbers, one for run duration and one for walk duration, and then it would play a sound alternately after the run duration and the walk duration. Exactly what I needed.
However, after the second time out, I discovered that I don't always hear the sound (what with moving my arms about when I run). When this happened, there was no easy way to get back in synch, as there was no easy way to tell when the sound meant run and when the sound mean walk.
So, for the second iteration, I've changed it, so there are two distinct noises. The run sound is an octave higher than the walk sound. Also, just to be extra sure, my phone now vibrates at the end of each period.
The second version is a great improvement, I didn't miss a single alert, and I still just have a simple program that alerts me after the run and walk times.
I don't think I would have guessed about making the phone vibrate if I hadn't have been out a few times. This is the power of iterative design. I made something, I tried it out, and then I improved it. I'll keep doing this too. One idea I have is to make it so I only have to enter the run duration, and then it will work out the walk time ( given that it's a two minute cycle ), but this isn't a big deal at the moment, the alert thing was.
Perhaps, when I can run for the full 20 minutes, I'll need to make a new program that alerts me halfway through a run, so I can turn round and head homewards, and then at the end, so I know when to stop. I'll probably get a wrist watch with a timer on it for this though...