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as seen from the Waterbot
Saturday, August 24 2019
location: Twenty Ninth Pond, Essex County, New York
During the night, I checked in on the progress of my import and found that it had, for the first time on this ridiculously large mass of data, successfully imported. Nothing fundamental had changed on my work-issued laptop (it still had just eight gigabytes of RAM and an AMD Ryzen 5 2500U processor), but, because the cabin has no internet, I only had a couple Chrome tabs open to things like the webpage of the wireless router I'd brought. Normally, I'd have several tabs with various YouTube clips paused in different places and Facebook and a couple other web sites built on top of huge Javascript frameworks that constantly ping servers and juggle complicated data objects. It was pretty clear that the import hadn't been able to complete in the office because my laptop didn't have enough spare resources to dedicate to it. This might even seem obvious now, but I don't actually have much experience with computers that can do something when lightly-utilized but completely fail when utilized at a moderate level.
At some point in the night, I moved to the cabin's living room and burrowed beneath a bunch of blankets due to the chill coming in through the open front door (it had to be open so the dogs could come and go as they wanted). Eventually Ramona joined me in my nest, while Neville got extra-snuggly under the covers with Gretchen in the bedroom.
There wasn't any coffee in the house, so after I got up, I made myself a cup of black tea and a hummus-with-tomato sandwich. I went down to the dock to eat it, and when I did, I saw a loon flying circles high above the pond. It was "Throckmorton," the title we give to any solo loon we see on Twenty Ninth Pond. By this point Gretchen was up, and she also got a glimpse of this you-have-to-see-it-or-you-weren't-in-the-Adirondacks sight.
I spent most of the day tinkering with my Waterbot on the table where I like to work, which is a table the middle of the front porch, overlooking the pond through the trees. I didn't have internet available to help me solve problems as they appeared, though I had downloaded some reference materials, and, when I eventually needed a reference for the L293D dual H-bridge, I was able to get it by walking to one of the cellphone spots. In this case, I went to the one where I'd parked the Prius last night because I wanted to use the Subaru's ODBII reader to find out what code was responsible for the Prius's check-engine light coming on (the first time I'd ever seen it). It was a 401 code, which suggested problems with an EGR valve, which doesn't look like anything I will need to worry about until next inspection.
To communicate between my work-issued laptop and the Raspberry Pi controlling the Waterbot (which all happened via either SSH or SFTP), I'd set up an old Linksys WRT-54G router (reflashed with DD-WRT of course) and then connected to it from both the laptop and the Raspberry Pi to form a local detached intranet (one completely disconnected from the Internet, which was hiding behind nearby hills). The internet connection was solid with this setup, but for some reason the Raspberry Pi kept spontaneously rebooting every two or three minutes, providing only a narrow window to test the various one-function Python scripts I was writing. I needed scripts to turn on and off (and reverse) the main propulsion motor and to also pull the rudder left and right. I suspect that the power fluctuations from driving such powerful motors was my problem, since I didn't include any circuitry to clean up power noise (and I was too far from my supplies to do it now). Another problem (which required lots of testing to confirm absolutely) was that one of the two motor controllers in the L293D dual H-bridge seemed damaged and incapable of going into reverse, probably from making it overheat in testing several days ago. Unfortunately, this was the H-bridge I'd picked to control the rudder. This meant that my Waterbot would only be able to turn left. But, since the Waterbot could also back up and turn off all propulsion, I could theoretically make it go anywhere even with this limitation; bigger things have been overcome on Mars rover missions.
As I worked, I'd periodically take breaks by going down to the dock, where Gretchen spent most of the day reading and hoping for the sun to break through the clouds. When it did, the dock was an idyllic place to be. But most of the time large Pangeas of supercontinental clouds blotted out the sun, and without it, the air was a bit colder than one would normally want. Eventually there was a sunny enough period for Gretchen to go for a swim. The water itself was fairly warm, but she wanted to emerge from the water into sunny conditions. In one respect, swimming conditions were significantly better this year than they had been in previous years: the invasive pond weed from last year had completely vanished. Last year, huge mats of it kept drifting up against the dock, and I'd have to fork it out of the water to free up open water for Gretchen to swim in. The weed had harbored leeches and perhaps other nasties, but it with all gone, so too were the leeches.
Once I had the Python scripts working as good as they were going to work, all that remained was to add some user interface controls to the Rasberry Pi's camera-viewing web page, which already included buttons to make the camera pan and tilt. I saved myself a bunch of work by copying the Disturbatron Javascript AJAX code and PHP backend code, which could already fire off Python scripts as needed. Doing this, I was able to build the entire user interface in about twenty minutes. The only bug it had was that the Reverse button actually made the boat go forward, whereas the Go button made it go in reverse. I was ready to test it in the water.
The nearest source of 120 volt power to the pond was an outlet on the front porch, so that was where I left my wireless router, and I soon determined that it had a range suitable for connecting with the Waterbot near the dock less than 100 feet away (no surprise there). So, while Gretchen went paddleboarding around the pond using the cabin's new paddleboard, I launched the Waterbot. Initially I was nervous to give it power and just watched its camera feed. I didn't know if the motor would be powerful enough to launch it into a distant shore before I could hit the kill button. But I shouldn't've worried; with that big NiCad impact driver battery, the boat had a lot inertia, and could only get up to a walking speed at best. It also tended to drive in loops, the result of the failure of the H-bridge to fully control the rudder. But otherwise, the test was a success; I could push buttons on a web page to make a distant device do different things. I've been wanting to be able to do this for years. Even Gretchen (when she returned from paddleboarding) seemed delighted, even though these sorts of pursuits don't interest her at all.
Later I cracked open a Lagunitas IPA and went up to the nearby cellphone spot (the one up the hill north of the cabin) with my laptop and phone and, using the phone as a USB tether, ceremonially added some files to a new Waterbot repo on Github. The dogs came with me and suddenly ran off somewhere whimpering with excitement, making me fear they might chase somethning for miles and get lost (like Ramona did last year), but they came back within a few minutes.
This evening, Gretchen and I sat in front of a small (but delightful) bonfire eating a meal of leftovers from her past week. She'd mostly been living on trays of prepared food she'd bought at the Honest Weight Co-op in Albany, things like their tempeh "chicken" salad, which now comes in a biggie-size. Tonight I ate a couple samosas spiced up with my own homegrown peppers. Then I transitioned to whiskey.
Our last pond activity was a post-sunset paddle clockwise around most of it in the canoe with both dogs. Ramona is always up for a ride in kayak, on a paddleboard, or in a canoe, but Neville requires encouragement.
I would be spending one more night, but Gretchen had to work at the bookstore tomorrow, so she'd be leaving tonight. After doing some cleaning and packing up most of our stuff in the Subaru, she and I and the dogs walked to the Prius up on the hill. She said goodbye, climbed into the car, and drove very slowly down the hill. As she did, I held both dogs so they wouldn't go running after her. I continued holding them until all of the visible light from the Prius had vanished. This must've been a sad thing for the dogs to see; on some deep, sub-cerebral way it was sad to me as well, even knowing we'd all be seeing each other again tomorrow.
We walked back to the house, I poured myself another whiskey, ate a xanax, climbed into bed, and started rewatching Extract, the only movie on my work-issued laptop. About an hour after Gretchen had left, the old cabin telephone started ringing. It's one of those original Ma Bell phones, complete with a rotary dial. When it rings, the thing you're hearing is an electromagnetically-hammered bell. I answered with a feeling of dread; Gretchen wouldn't be calling unless she was experiencing an emergency. Happily, the emergency was just that she'd forgotten her wallet (which was probably in the Subaru). She wanted me to give her the numbers from one of my credit cards so she could buy some gas.
Gretchen called again 20 minutes later to tell me how things had gone. Apparently there are anti-fraud rules at most gas stations preventing people without physical cards from buying anything. But some poor working class woman at the station took pity on Gretchen and gave her the $4 worth of gas she figured she would need to make it home. Gretchen had no money, but she had several ears of organic sweet corn and a tub of unopened hummus, both of which she insisted the cashier take in exchange for this kindness.
I hadn't known this, but the "black tea" I'd been drinking all day had been decaffeinated, meaning I hadn't had any significant amount of caffeine at all today. Somehow I hadn't even noticed, probably because at some point this afternoon I took a recreational 90 milligram dose of pseudoephedrine. It's a stimulant, but it's different enough from caffeine to have failed as a substitute in a number of crucial biochemical ways.
Neville and Gretchen on the dock today. Note that Gretchen is wearing a warm shirt.
Neville, Gretchen and Ramona on the dock.
Neville with the slope down to the dock behind him.
Neville on the cabin porch.
Ramona on the porch.
The Waterbot on Twenty Ninth Pond.
Shoreline plants. Photo taken from the Waterbot. Click to enlarge.
Gretchen paddleboarding. Photo taken from the Waterbot. Click to enlarge.
Me and Ramona on the paddleboard.
For linking purposes this article's URL is:
http://asecular.com/blog.php?190824 feedback
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