Heart rate 3

I wanted the heart rate monitor mostly to see what my heart does while I'm dancing, and I finally have a usable data set from my Bollywood class, with Shaira Bhan:



As you can see, my heart gets a lot to do during this class. 185 might be considered too high for me, but I don't notice it and I'm having fun. The 185 peak was during the sequence of jumps where you lift your knees and move your elbows towards the knees. As you can see there is also a very odd dip, at about 21 minutes in, where my heart rate went down to 115. Here we practiced jumping up from a sitting position while keeping your head down and moving it up in a "cool" fashion. As you can see, we didn't do very well, as it took several minutes before we started dancing again. The software that came with the monitor calculated I burned 1076 kCal during the dance session (I assume it uses my weight and my heart rate to calculate this).

I also gathered more data of me cycling, so I updated the script to allow comparison of two graphs. It now requires additional parameters url2 and offset. Here are two days of cycling, I tried to match up the peaks (which are overpasses).

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As you can see the second time (in red) I had to wait for the traffic light at the bottom of the US-101, which meant the peak isn't as high. Here is the same chart comparison for the way back:



Here there is a distinct difference in the beginning, which is easily explained. The red graph starts with me sitting in a chair at Google, working on my feature. The green graph starts with me leaving my Bollywood dancing class. This is also why the green graph is shorter: the dancing class is in a building that is closer to my house.

Heart rate monitoring 2

Here we have me resting:



It looks as if a lot is happening, but if you look at the scale you can tell it is actually quite low. I tried measuring myself while sleeping, but the problem with that is that the watch keeps beeping (despite me having beeps off) which wakes me up. You'd imagine my heart rate while resting and while bathing are very similar, but this is not the case:



while bathing my heart rate is much higher, even though I feel quite relaxed. Maybe this is because the water is hot? Finally, here is an actual exercise session, including 10 minutes cycling, followed by lots of walking and running on a treadmill. The peak, where my heart rate is 182, is when I'm going 8 miles/hour on a slope of setting 1.

Heart rate monitoring

I'm not sure if this should be posted as "Emerging Drake" or as "Occlusion Culling"... It fits in both categories. But since I might create more projects regarding heart rate monitoring, I decided to post it here.

My mother recently gave me a heart rate monitor, which has the option of uploading the data to a website. Fortunately there are various ways of retrieving the data yourself, and processing it. I wrote a little script, that, when provided with an url= parameter (try "cashimor.xml") plots the data from the file. I'm not sure if this is a generic file format, or whether it only applies to the Timex Ironman with data xchanger. Anyway, here is the first graph:



It shows me having breakfast (it seems reading books causes my heart rate to drop below 65) and then, about 14 minutes after the start of the measurements, carrying the bike downstairs and cycling to work. At 27 minutes in you can see the bridge over the US-85, causing my heart rate to go up to 135, and then down to 100 as I glide down the other side and wait for the traffic light. At 34 minutes in you see the bridge over the US-101, which is longer, steeper, and more scary (I need to cross a lane of traffic). It goes down more gradually because the light was green. Near the end you see me climbing into the parking lot of Google. Here is the second graph:



It shows the part after the cycling, where I sit in my chair and code. There's a small peak when I went for tea (13 minutes in). And here is the third graph:



Where I cycle back. Since the most resources claim my ideal heart rate for exercise is 127, this looks pretty good.

iDrake schematic, version 1

It seems most requests are for the iDrake with LCD display, so that is the first one I'll build. To make a PCB, I first need a comprehensive schematic. This isn't one, but it is the beginning of one. I'll work on it more tomorrow... Or the day after... Or whenever I'm not working on my novel.

iDrake™

Just in case Apple is going to move into the Drake space next, I present the iDrake™ in this blog post. The iDrake™ is now for sale for $49.99. You can Email me for more information. So far I have sold one. The specifications are very open, but should fall within the range of the other drakes presented here. There are optional add-ons (GPS, GSM, et cetera) that would make it more expensive. Feel free to discuss these things with me.

Adding a segment: the middle vertical bar

My first idea for a segment to add is the middle vertical bar. This will not be split in two, but instead will be the whole length. This makes some letters better (B, D, |) and other characters possible ($, +, T, M, W, w, m, x, X). As you can see, there is still a lot of room for improvement.

7 segment font

I've been playing with fonts for a while, and I've always wondered about the least number of bits that is needed to display a character set. One option is to use a 7 segment display, as shown in this picture. Sadly, it doesn't handle all characters, and a lot of them are messed up. On wikipedia there is a 14 segment display, which does handle most characters correctly, but 14 bits seems a bit excessive. I'll see if I can find some alternatives that use less segments, but still produce acceptable results. If you have ideas, please let me know.