Friday, June 9, 2017

StuntMIP

Hello blog! Longtime no see. Sorry to leave you lying fallow for so long, but it's been a busy couple years and I'm only now catching up. In the meantime, I've been to grad school, got my master's, worked a few different jobs in and out of my field, and got a couple dogs.

Leading off with the primary thing I've built in the meantime, let me introduce you to StuntMIP. Based off of the UCSD Coordinated Robotics Lab's proven MIP design, I worked to get it ready for the challenge of doing a loop-de-loop. Past getting it to balance, the primary design challenges were now to get it moving fast enough to sustain contact with a track, and to go in a straight line on its own at high speed.



In order to achieve high speed travel, I first had to find some way to make sure the robot could travel in a straight line. It seems like an easy problem, especially when you've got encoders on the wheels, but dead reckoning by wheel rotations wasn't precise enough, so it needed to be able to reference its outside environment. I opted to use line following, given that it's a pretty robust system, with plenty of work done on it over the years. While most line-following robots work on a binary principle of being either on or off the line, I needed something more granular and continuous. So I mounted 4 reflectance sensors on the base of the robot, and implemented a weighted centroid algorithm. Each of the sensors read a reflectance off the underlying surface, which after calibration was mapped between 0 & 1024.

Most line following robots work a fixed distance from the ground, which results in the algorithm moving the perceived location of the line to the middle of the robot. The algorithm works on the difference between the highest and lowest readings, with the general assumption being that the sensors not on the line will return a reading of 0. I rewrote the sensor code to subtract the lowest reading all of them before implementing the algorithm, which resulted in the algorithm returning a more accurate result.

The next major problem was getting the robot to accelerate smoothly up to a high speed. It would accelerate up to a point, and then it would wobble a bit and fall down. It turns out that the control gains for the MIP were heavily weighted to keep the robot upright, which makes sense, since falling down is a failure condition. As the MIP accelerates, it leans over, and the faster it accelerates, the more it leans. So when I was feeding in a reference to encourage it to accelerate, the controller was only willing to go so far before trying to come back upright. After playing around with the control gains, I wound up going with a significantly looser set of control gains. StuntMIP would roll back and forth a bit while trying to stay in place, but was able to achieve much higher speeds.

StuntMIP was a really fun project, and while it didn't manage to do a loop-de-loop, that journey is left to some other adventurous student.

Sunday, May 28, 2017

Optimism about Discovery

By which I mean, the new Star Trek series. I've been waiting for this for a long time, and I was really excited to see the first trailer.



I've been seeing a lot of complaints across the internet about this, which I understand is in accordance with the prophecy that Star Trek fans (Trekkies or Trekkers, depending on your own personal taste) will heap hate on any new series or movie until they wind up arguing about how it's truly the best part of the whole franchise. Still, because if I don't write these counter-arguments down they'll just stay in my head and bug me, here they are!

Take #1: It looks too futuristic! Why doesn't it look like "The Cage" (the original Star Trek pilot) which took place at a similar point in the timeline? What about continuity?

I'm all for the nostalgia of revisiting early Trek. One of my favorite things to come out of the internet in the past few years has been the proliferation of Star Trek fan films expanding on the original series. Star Trek New Voyages, Star Trek Continues, Prelude to Axanar, Starship Farragut, these have all been a lot of fun to watch in lieu of having official new Trek, and I can't commend them enough. All of these productions do a marvelous job of recreating the look and feel of the original series, and building onto it in exciting ways. But they're still fundamentally tied to art direction decisions that were made 50 plus years ago, and it's entirely unreasonable to expect that a modern, high budget television production is going to try to paint inside the same lines. Plus, we've already seen a modern take on those uniforms and ships in the Kelvin timeline movies, so this show has to distinguish itself in some way.

50 years ago, the bridge of the Enterprise looked sleek and futuristic, today it looks like something from an Buck Rogers adventure serial. Which is cool! It's just a product of its time, much like this show will be. And for those who'd complain that this ship seems too dark, and the uniforms too military, it's worth noting that one of the primary creative forces behind this is Nick Meyer. His first contribution to Star Trek was Star Trek II, and he's the reason why the bridge was darker, the uniforms went from bright tunics to maroon jackets, and the interior of the ship looking more like a submarine than a promenade.

As for continuity, I really hope they hire Bruce Greenwood and Zachary Quinto to do a single scene on the bridge from the Nu-Trek movies as Pike and Spock in the Prime universe, dressed in the same uniforms as the Discovery/Shenzhou crew, just to clearly state "this is how it looks now". They can just answer a hail, say they're going to Delta Vega, and then we'd never see them again.

Take #2: A species "determined to detect the coming of death" sounds dumb!

Well, it's not any less dumb than telepathy, telekinesis, dream-invading, or spontaneously evolving into a being of pure energy, all of which has happened at some point or another in Trek. Let's see how this plays out! Plus, Lieutenant Saru is played by Doug Jones, who is pretty great.

Take #3: They've ruined the Klingons! Look at them!


Let's look at the evolution of Klingons through the history of Star Trek.


The last one there is the new Klingon that has been generating so much controversy. It's different from the others, sure, but there's clearly been a whole lot of variance in the appearance of Klingons through the years. We might be looking at a big change in the visual design, but it's nowhere near as big as the jump from the original series to the first movie.

Take #4: Seth McFarlane's new show, The Orville, looks way more like Star Trek than Discovery!

Well, yeah. It does! It seems to be drawing a lot of its visual inspiration directly from TNG, so it'll look very much like that. I'm excited about the idea of functionally having two Star Trek series this coming fall, even if one is a goof on the premise. From watching the trailer, it seems like the comedy will largely hinge on the bumbling main character, which I'm a little tired of as an organizing premise.

Star Trek can be hilarious, but it's usually a character-driven humor, putting well-established characters into situations in which they're uncomfortable. I'm mostly thinking of Picard trying to deal with children, which was always a hoot to watch.

Take #5: Bryan Fuller left the show! All is ruined/lost!

I'm super stoked that Bryan Fuller was involved in Discovery, but it was unlikely that he was going to be able to run both American Gods & Star Trek Discovery. Given that they originally both had release dates in May, it was almost impossible that Starz was going to let their prize showrunner off to produce another network's flagship product at the expense of their own. We're getting a show for which Bryan Fuller wrote the core outline, and the first couple episodes in their entirety, which sounds like a pretty great show to me. It's a bummer that he isn't involved with the show going forward, but I'll take a show he had a hand in creating with no complaint.

It's worth mentioning there's been a response to the trailer which has run something like 'where are the white dudes? Why aren't they in charge? The SJWs are ruining my Star Trek, arghbarghlarghargh!' To these people, I recommend they watch Star Trek again. I think they'll find it means something different than they thought.

Tuesday, October 9, 2012

Tournament Report: San Diego 3 Weapon Open

This past Sunday I went up to Cathedral Catholic High School in San Diego and fenced in the local three weapon open. Well, it was a really small tournament, and thus short, which is good, as I pulled dead last. If I'm gonna do horribly, I'd at least like to do so in a timely fashion.

With eight people total participating, we had a full pool of all the competitors, and I went two and five. I don't feel great about how I fenced a couple of those, there were a couple where I was simply caught flat footed repeatedly, and others where I didn't adapt quickly enough. I felt okay about how I was moving, it's my tactics that are getting me in trouble. Anyway, another two weeks 'til the next tournament, I've got some stuff to work on.

Friday, October 5, 2012

What's Making Me Happy This Week, Pt. 2

A few weeks ago I was ruminating over how to connect my Xbox to the internet, as it didn't have a wireless adapter and the modem was in my room. I mentioned the idea of running an ethernet cable through the house to my roommate, and he proposed using the cable splitter that was right in front of the TV and the Xbox to set the modem and router up there. And lo, it was done. Why is this important, you may ask? Because, once again, I have Netflix streaming through my Xbox to my TV, and it is glorious.

I'm using this newfound access to catch up with a show I heard about a year and change ago that was supposed to be rather excellent, and I can now confirm that is true. 'Terriers' is based in San Diego and follows two down on their luck, unlicensed private investigators through their various misadventures. It's smartly written, well acted, and in the first two episodes it hasn't made a misstep, which I feel is rare. There aren't a lot of shows that don't have terrible pilots, but they came out swinging, which is just as well because there's only half a season of it. I'm usually leery of getting into TV series, as I'm a completionist and want to watch every episode of something (which is terrible for my time management). An unintimidating thirteen episodes is just about right to hook me, and hopefully it'll leave me wanting more.


The second thing making me happy this week is rediscovering a game called Braid. It's essentially Super Mario, in that you play a small fellow who stomps on goomba-creatures and defeats bosses in order to find and rescue a princess, who is perpetually in another castle. However, it is so much more than that. In addition to your usual running and jumping, in Braid you can reverse the flow of time. In each stage of the game, this works differently, and results in some very fun, occasionally frustrating puzzles. The story is great, the music is amazing, the art is astonishingly beautiful, and it's challenging. You can't ask for much more than that. And it's cheap! You can grab it for $10 off the Mac App Store or on Steam.


Thursday, October 4, 2012

Brewing Mead

For a while now, I've been fascinated with the idea of brewing up a mead, which is essentially fermented honey water. I looked up some instructions, and what struck me was how simple it was. In short:

Take 10-18 pounds of honey (depending on how dry or sweet you want your mead to be), and then mix in about 4 gallons of water. I grabbed 10 pounds from Mikolich Honey at the Little Italy Farmer's Market the day before.


Bring the entire concoction to about 190º farenheit and leave it there for at least twenty minutes to pasteurize it. While that's happening, skim off the foam that forms on top, as this is full of nasty junk you don't want in your mead.


Cool your must (the word for unfermented mead. Cue the 'more you know' rainbow!) down to 70-75º so that you can pitch the yeast. Then move the must to the sanitiized carboy. If you look carefully, you might see a wild, bearded 'Groth' assisting with this part of the operation.


Pitch the yeast! Then store in an appropriately cool spot (70º for this particular yeast) for a month before racking to a secondary fermenter. Some folks have suggested racking to a tertiary fermenter after another two months, and then aging it for a year. We'll see if we follow that particular plan, as it seems to be rather a long time to wait for a tasty beverage.

Special thanks to Groth and Ashok for being the brew crew for this one!

Thursday, September 27, 2012

Comic Con 2012

Okay, so my annual Comic-Con post is tragically late. I beg your forgiveness! Oh wait, no one reads this. Crisis averted.

Anyhoo, this was a weird year at Con for me. I didn't get a four day pass, I actually didn't get any passes in the first couple of sales. I got very lucky in that I have a great friend (Rey Guerrero, who is a mensch, a champ, and a lifesaver) who happened to be in possession of a guest pass that he was happy to give to me. Which, as I've said, makes him a mensch of the highest order.

So I went out to preview night with my good buddy Peter, and walking into the convention hall felt a lot like coming home. The dull roar of the convention floor, the sights of all the cosplayers and exhibits, it's a different combination every time, but it's still familiar. This was my sixth con, and each time I find more and more to discover. For the second time at Comic-Con, on Preview Night, I ran headlong into Mr. TJ Tallie, which mostly served to remind me that for an event with about a hundred thousand people in attendance, you can still just run into people you know.

On Thursday I went down to catch W00tstock 4.0 with my friends Dave and Katherine, which as ever was about the funniest five hours of my con. Featuring the usual cast of ne'er do-wells, it featured a couple new faces that I hadn't seen before, and who were ludicrously entertaining. One of these new faces was Joseph Scrimshaw, who made me laugh so hard my abs hurt the next day.



On Friday I milled about downtown for a while, checking out a lot of what I call 'con-adjacent' events. A particularly fun one was the exhibition of all the Batmobiles over by the Hilton. These ran the gamut from Adam West's jalopy to Christian Bale's tumbler, and it was pretty awesome.


Later that day, I wandered up the street and right into the middle of a zombie walk. A mile long parade of zombies, striding down 5th avenue. It literally did not end, I kept trying to go against the tide of made-up, blood smeared people. Some of them were very well done, some of them were, well, less so. It was still an impressively sized spectacle. And I was also struck by how in-character some people were. A little too convincing, sometimes.

I then proceeded to the Nerdist Podcast Live for the second year running, and got to watch my favorite podcast crew riff, drink, and be incredibly profane. As much as I love the usual cast of Chris Hardwick, Jonah Ray and Matt Mira, their guest, John Barrowman, really stole the show. Mostly by telling the dirtiest stories, drinking like a fish, and molesting the cast and several members of the audience. So, in essence, a great show, which you can hear the podcast of, if you're so inclined.

On Saturday, I headed downtown to soak in more con-adjacent stuff, one of which was the superhero art exhibit at Michael J. Wolf Fine Art Gallery. Every year they have some manner of superhero art up, but they had some pretty excellent art up this year, including this Batman portrait.


Later on I wound up linking up with my roommates Lucky and Debra to check out 'The Walking Dead: The Escape' event at Petco Park. Essentially an obstacle race through the park, but with ZOMBIES! It was a lot of fun to watch, the zombies were really committed to being scary, grotesque and didn't lumber too much, but picked some strategic 'choke points' and managed to tag almost everyone who went through.


Following that, I actually headed back to my house and then walked over to the Ruby Room, a local bar/venue to catch a nerdcore hip hop show featuring MC Frontalot. It was pretty excellent, for a couple of reasons. One, I've been a fan of his for about 5 years now and have never seen him live. Then, during an opening act I'm leaning against a pool table, having a beer, and glance back at the guy who just leaned against it a few feet away and it's MC FRONTALOT. DUDE. I mean, I didn't say anything to him or anything, 'cause I don't want to fanboy, but that was awesome. The music was awesome, it was great to see him perform live after listening to his albums so many times. The second reason it was exceedingly awesome was the interstitial performances between musicians being Star Wars themed burlesque dancers. Sexy Boba Fett, Sexy Stormtrooper, and of course, Sexy Slave Leia. So, you know, that was pretty excellent.

Sunday I went back to Comic-Con proper, the exhibit floor. I actually saw no panels this time around, I literally just walked around and tried to soak in as much of the cosplay and booth fun as possible. One of my favorite booth displays was Geek Chic's, as it featured fine, handcrafted wooden furniture & faux weapons, with an eye towards gaming tables and paraphernalia, which I would totally get if I had several thousand extra dollars lying around. The cosplay was also excellent, as you can see below. The lady Dr. Who cosplayers are really becoming a staple at Comic-Con!


All in all, it was a great con. It was my Nerd Christmas, and now I just have to wait and try to stay on the good list until next July.

Sunday, September 23, 2012

Tournament Report: Orange Coast 3 Weapon Open

I just got back from the tournament, after getting knocked out in the round of 32. Despite that, I'm actually feeling pretty good about it. I fenced well in pools, going 4-2, a pretty decent improvement over last time. Then in direct elimination, I pulled a guy I'd fenced in pools in the round of 64, and beat him pretty handily. Then I pulled my coach in the round of 32. Tedd and I had a pretty decent bout, 15-9, and he went on to take second. So while I found myself out earlier than I planned, I feel like I fenced well, better than I did at the last tournament. So, out of 54 fencers, I took 21st overall, which isn't a bad day at all. And then I got to go home and have a 'funky monkey' from a local coffee shop to ease the heat. Good day!