Saturday, May 19, 2018

Almost

Nina almost got a Flaka yesterday. She said that for the very first time, the board kept turning while she was sliding backwards. She probably finished the 360 degree rotation, and maybe even a bit more. But she did not realize she was done until afterwards, so she fell onto the sail. But still, that's big progress.

We sailed Lewis Bay in NE wind yesterday for the first time. In NE, we usually go to Duxbury, Chapin, or other spots, but the tide was too low yesterday morning for most of those, and the wind was predicted to drop early. Lewis Bay was a bit gusty, but otherwise quite nice. But there was a surprising amount of ferry and boat traffic.

I almost got to test my Raspberrry Pi Zero "plug and play" GPS while windsurfing for the first time yesterday. Here's what the setup looks like:
It's a Raspberry Pi Zero, a Stratux GPYes USB GPS dongle, a 2500 mAh USB battery pack, a USB cable, some vecro, a zip lock bag, and a waterproof back. The cost for the entire setup is about $50 - about 1/4th or 1/5th of a GW-60 GPS watch. I did wear this while windsurfing, but encountered one little problem: the battery had switched itself off! No test data this time, bummer.

I had noticed a few times before that the battery turned itself off, but was never quite able to figure out when that happens. When it happened before, I thought that I had forgotten to charge the battery, or that the battery was dying - but I was wrong. A little internet search yesterday showed that the "sleep" function is standard for USB battery packs. They are meant to charge phones, which usually happens at 0.5 amps or more. If the current drops below 0.1 A, they decide that the phone is sufficiently charged, and go to sleep. Lazy bastards!

I did a bit more testing with a USB tester today at home, and discovered why the sleep issue was so confusing. Using a variety of USB dongles and hub, I saw that the battery goes to sleep after about 30 seconds if the current is continuously below 0.1 A. It turns out that the Pi Zero uses just about 0.1 A when it's doing nothing. A USB GPS dongle needs about 20-40 mA, so when the dongle is plugged in, the current increases to about 0.13 A. Therefore, the battery always stays on when I test at home.

One of the things that needs current is WiFi. It's usually on when I'm at home, although the script that starts the logging turns if off when a GPS dongle is connected to extend the battery life; that drops the current by about 20-30 mA. When the dongle is pulled and the logging stops, the WiFi is automatically turned back on.

But what happens when WiFi is on, but no network is available (which is usually the case when windsurfing)? It turns out that not being connected to a network has about the same effect as turning WiFi off - the current drops to about 70 mA (with no GPS dongle connected). So that's what happened yesterday! I turned the Pi on before rigging, and connected the dongle about 15 minutes later ... without checking if the battery still was on. But the lazy thing had gone to sleep.

The little test failure just underscores that you can't see much when you're flying blind - the Pi GPS logger needs some kind of display. I've got a little 2.13 in e-paper hat that has exactly the same form factor as the Pi Zero, and got the demo programs to run. Getting it to work with the logger will require a bit of trickery, since there don't see to be any Java drivers for the display. For now, I'll probably go with some primitive form of inter-process communication between the logger and a Python or C program for the display, maybe through a file on a RAM disk. That's the easiest solution that comes to mind, and would make it quite easy to support other kinds of displays, too.

Saturday, April 28, 2018

Great Fun at the Nationals

We're at the US Nationals in Seaford, Virginia, and we're having a blast. How could you not at an event venue like this?
The venue .. before the crowds arrived
It's Dave Kashy's place, where we have raced several times before - the perfect place for a regatta. Even better is the organization, with race results posted online shortly after the races, and group dinners at great local restaurants. It's almost too easy to make new friends, and much more fun to race with friends than with strangers.

I'm in the Kona fleet, so I don't have the usual "bad gear" excuses for placing near the bottom of the fleet - it's all me. But I don't really care, it's lots of fun. It's great to see all these fantastic windsurfers on the water. 
Kona racing

Sunday, April 22, 2018

Hatteras Report

Sorry about the long gap between posts - it's been way too windy the last two weeks. We spent that time in Hatteras, and it was windy every single day. Both Nina and I had to take a day off in the middle because we were to exhausted. But we also wanted to be (somewhat) fit for OBX Wind week, where we both participated in the long distance race. Nina also did the freestyle clinic with Phil Soltysiak; I was signed up for the slalom races, which turned out to be very interesting.. more about that later.

Seeing more than 200 windsurfers compete in the long distance race was amazing - check the picture below:
OBX Wind long distance race. Photo by Donald Ferguson
We did a total of three long distance races, one on Wednesday in wind around 15-20 mph, and two on Thursday in 25-35 mph wind. Each race was out to the reef and back twice, which was about 13 km (8 miles). Even though the wind dropped during or right before two of the races, leaving many competitors slogging, there were lots of happy faces and high-fives after the races. Almost everyone played nicely, but a few racers regarded their placing in the race as much more important than adhering to basic safety or right-of-way rules. Both women in our house who competed had incidents where a racer either forced them to get of the board to avoid a crash, or passed dangerously close (in the middle of the course, with plenty of space to spread out). It is quite unlikely that they will compete in future OBX Wind long distance races. 

Nina did quite well in the long distance race, placing second in the Women's Open division (which had 8 women competing), and leaving all 18 women in the freeride division, as well as more than 100 male windsurfers, behind. I accomplished my goal of finishing all races without breaking anything. On day two, that required switching to freeride gear (Tabou 3S 96 and North Ice 4.7), since there was no way I would have made it through the course with any semblance of control on a race sail and/or slalom board. Since I can actually go faster on this gear than I would have been on slalom gear in the conditions, I managed to squeeze into the top-25 overall, which I am quite happy with.

The slalom racing was quite interesting. From the very first day on, I had realized that the "chop" at the Corpus Christi and SPI spots had seriously spoiled me. The chop in Avon in 20 mph wind (according to the highest nearby wind meters) was much higher and more chaotic than the chop at Grassy Point in 30 mph wind. I (re-)discovered that I really don't like to sail slalom gear in these conditions. After a week of trying and adjusting things, I got somewhat more comfortable, managed to keep most of my jibes dry, and even plane through one occasionally ... but then, the slalom races started. In the second race, I managed to come in in the top third of the ~20 racers, but it quickly went downhill from there. With all the chop around the marks and the distractions from other sailors, I blew most of my jibes. Since I did not wand to be run over (and since my starts sucked, anyway), I decided to let most of the field go ahead before getting to speed. That turned out to not be a smart decision - I had the pleasure of sailing through everyones chop, and then had to avoid all the others who had fallen in their jibes. More dropped jibes, even less confidence ... not a good feedback loop! The final straw was the guy who absolutely had to improve his rank from third-last to second-last by first passing me upwind, with about a foot distance between our boards, and then again passed me fully planing about 2 inches from my head when I was down at the mark. Really? You're at the tail end of the field, but you're such a great sailor that passing someone this closely is safe? So that you can come in 13th instead of 14th? At that point, I decided that slalom racing was definitely not for me, and went in. I could have come to that conclusion earlier, considering that I usually sail way upwind, downwind, outside, or otherwise away from the crowds; but I had previously participated in one slalom series (and several longboard races) where the testosterone-level seemed a lot lower, and everyone sailed more considerate. It just gave me the wrong idea that that's typical.

Nina's choice of doing the freestyle camp was a much smarter one. She learned a lot, and made progress on several moves she worked on. Compared to many racers who displayed the attitude "get out of my way or else", the freestylers were a much friendlier crowd - several high-level freestylers stopped by and gave her tips when they saw the moves she was working on, or demonstrated the moves for her. The freestyle competition was also absolutely awesome, with great moves by top PWA pros Youp Smit and Phil Soltysiak, East Coast freestylers like Mike Burns, Chachi, Max Robinson, and others.
Youp Smit freestyling
We left Hatteras to go to Seaford, VA, where the US Nationals will take place in a few days. I'll be in the Kona category, where I have sailed in before and loved it. We got lucky and scored a really nice AirBnB close to the event - here's a picture from today's sunrise, taken from our apartment:


Tuesday, April 3, 2018

For Pi Players


A couple of people have expressed interest in also playing around with Raspberry Pi-based GPS loggers, so I have posted some very brief instructions and a ZIP file with the code I use at http://www.ecwindfest.org/GPS/. If you want to play along, you'll have to figure out all the Pi things on your own - Google is your friend! I'll entertain any suggestions for improvement, but can't make any promises - I hope to windsurf a lot in the next few weeks, and spend the rest of the time talking about windsurfing, drinking beer, and sitting in the hot tub :-).