nobody else saw, not even me when reacquainted with the pulses of the everyday world.</p><p id="9c95">It may have been wandering, or boredom, or self-destructive behavior that led me into the bathroom at the blue level of Madison Square Garden with Keegan, a friend from boarding school. I was getting ready to drop two windowpanes of a four-way hit. Whatever I was seeking, I knew that, at the very least, this dose would provide a counter-irritant to douse the peat-fire of boredom and wanting burning in my guts.</p><p id="4657">Keegan asked me how many panes I wanted to take.</p><p id="c93a">I asked, “how many are you going to take”?</p><p id="9068">He said, “two”.</p><p id="46ca">I said, “I’ll take two, then.”</p><p id="b8c7">Soon after I took them he told me that he had dosed on this same acid two days before, which would mean that he had some resistance to the batch and was doubling his intake to make sure he got high. What it meant for me was that if the acid was any good I was going to get very high, and the acid was good.</p><p id="a94e">Whether what Keegan had done was “mean”, “unfair”, “stupid”, “dangerous”, “funny”, or “not a big deal”, wasn’t a question I asked at the time. It was two decades before I began to realize that some of my “friends” were not my friends. It may be of no surprise to people older than fifty that many of the people I once called “friends” were really transactional acquaintances forged in a furnace of boredom and need. At some point in my life (like, about age forty) there was the awful realization that some of the people I referred to as “friends” were simply people that let me hang out with them. They didn’t actively humiliate or shun me, and so, to my adolescent pollywog brain, they were “friends”, even if there was no reciprocity in our relationship.</p><p id="ba48">Keegan was not someone I hung onto. In the brutal pecking order of boarding school hierarchy he and I were roughly equal, though we shouldn’t have been. Keegan was smart and funny, but he was also overweight, messy, and occasionally obstinate, in the kind of peevish way that eventually stops making sense. In a milieu where sports, good looks, and emotional control counted in the calculation of your social credit score, I could fairly count Keegan as an “equal” despite the fact that he was a more compelling, charismatic, and engaging character than I was.</p><p id="9ded">Keegan had another strike against him that may be hard to explain nowadays. His parents were divorced and he was being raised by a single mother. Why that information reflected poorly on him is a topic for another serving of dreck, but there is no question that my dysfunctional, alcohol-soaked, “in-tact” nuclear family gave me a lift. Keegan’s mother, who was smart but stranded economically (though not so stranded that she couldn’t afford boarding school for her son) came to parent’s day alone, or didn’t come at all. While that information seems like it would be the last thing that teenage boys would care about, somehow it factored into the equation, and, in ways that confuse both logic and analysis, made it easier for us to take Keegan himself less seriously.</p><p id="6a81">As I look back at it, I don’t think Keegan was being a dick when he gave me the double dose. We can explain it away by using the euphemism, “he was being mischievous”. He saw it as a prank. Had he not died of a drug overdose when we were in our twenties, I am certain that today he would be willing to either apologize or explain to me why he didn’t need to apologize. I’m sorry he can’t do that.</p><h2 id="ba57">Part II: The Trip</h2><p id="4aa8">After dropping the acid in the bathroom, a metallic flush began on my tongue and filled my entire mouth while we were walking on the concourse towards our seats. I was seeing vivid color trails before any music started. When the Grateful Dead came out, I couldn’t quite fathom what was happening. All I saw was Gerry Garcia’s great gray set of hair mushrooming and breathing as he took the stage. His hair kept expanding until it filled more than a third of the Garden. Then then band began to play.</p><p id="6d9d">Here is the a recording in the concert. There is a crash at the beginning of the opening number, <i>Mississippi Half-Step</i>, which I clearly remember, though at the time, I couldn’t make any sense of it.</p>
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<iframe class="" src="https://cdn.embedly.com/widgets/media.html?src=https%3A%2F%2Fwww.youtube.com%2Fembed%2Fs_PakceAHxs%3Ffeature%3Doembed&display_name=YouTube&url=https%3A%2F%2Fwww.youtube.com%2Fwatch%3Fv%3Ds_PakceAHxs&image=https%3A%2F%2Fi.ytimg.com%2Fvi%2Fs_PakceAHxs%2Fhqdefault.jpg&key=a19fcc184b9711e1b4764040d3dc5c07&type=text%2Fhtml&schema=youtube" allowfullscreen="" frameborder="0" height="480" width="854">
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</figure></iframe></div></div></figure><p id="06c9">Throughout the concert Keegan and I stayed in our seats. At one point a Deadhead “twirler” came up to our tier and spent what seemed like hours Grateful Dead dancing.</p>
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<iframe class="" src="https://cdn.embedly.com/widgets/media.html?src=https%3A%2F%2Fwww.youtube.com%2Fembed%2FtmBIgvOYfLw&display_name=YouTube&url=https%3A%2F%2Fwww.youtube.com%2Fwatch%3Fv%3DtmBIgvOYfLw&image=http%3A%2F%2Fi.ytimg.com%2Fvi%2FtmBIgvOYfLw%2Fhqdefault.jpg&key=a19fcc184b9711e1b4764040d3dc5c07&type=text%2Fhtml&schema=youtube" allowfullscreen="" frameborder="0" height="480" width="854">
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</figure></iframe></div></div></figure><p id="ef40">I must have been smoking. I didn’t really smoke much as a kid, but I didn’t “not smoke” and since almost everyone in the world smoked, I sometimes did. Two girls came up to our seats and asked to bum a cigarette from me. I ha
Let’s make a Maze Solving Robot? A robot traversing a labyrinth \o/
In this post, we will make Tribot v1.0 travels along the right wall through a maze. Boxes, piles of books, or large MDF wood work well for the maze walls. You could even build a maze out of Lego blocks!
We need to make Tribot v 1.0 respond correctly when it’s following the wall to its right then runs into a wall in front of it.
When the Tribot v 1.0 runs into the wall, the Touch Sensor will be pressed, at which point we can make the Tribot v 1.0 back up, make a quarter-turn to the left, and follow the wall it just ran into with the help of IR Sensor.
Here is our maze bravado ;)
The challenge is to always follow the right side of the wall. See an example of a maze gif solution.
We are using EV3’s IR and Touch Sensors. See this link for constructing your own robot.
And here is our video lab:
In robotics autonomy conventionally refers to the degree to which a robot is able to make its own decisions about which actions to takenext. Thus a fully autonomous robot would be capable of carrying out its entire mission or function without human control or intervention.
However, at first, our robot is only a semi-autonomous. It really has a degree of autonomy but require some human supervision ;)
Our R_Follower_Robot v1 code must pass these 10 Maze Test; to test the code you need a wall with a corner and an opening, or you can use a full maze (which is a little more fun:)
Here is our first solution approach, graphically (thanks to my friend Pompermaier for the idea:)
Now here are some guidelines for you to use or adapt the previous code:
Step-by-step:
1º Step: if none of the sensors are activated, we will take care of the navigation in a range of 5–12 cm off-the-right-wall;
Code like this:
2º Step: If we hit one of the walls, stop, return and take the left direction;
Code like this:
3º Step: if we find a gap large enough, stop, advance a little, take the right 90º turn and advance a bit; If nothing happens, return navigation in the first Step and repeat the cycle again :b
Code like this:
Maybe you should shift some values on your benchwork. You can improve the program even more by adjusting the Steering parameter to control the sharpness of the Tribot v1.0's turns. But anyway, I think you’ve got the idea, right?
Here are some Tips'N Tricks:
. Give Tribot v 1.0 enough room to turn whenit gets to a corner;
. Makeuse extensively of EV3’s Port View;
. Slowing the Tribot v 1.0 down should help a lot;
. If Tribot v 1.0backs up or spins a little too far try few values for distance and rotations;
. Before moving ontothe next section ofthe program, retest the code from earlier to make sure it still works as expected;
. When IR Sensor faces an opening, it will suddenly reada much greater distance than it did when following the wall; spent some time tinkering with this value; even the presence of your body is influential for this settings; mark the distance ata point of90º's corner;
. When you're done testing, you can use Sound Blocks for debugging; but be sure to test the program again after removing them to make sure that it still works;
. When you are sure thatthe program fulfills its requirements, see how it works in other situations; For example, adjust the spacing ofthe walls (make corridors narrower or wider) to see how that influences the Tribot v 1.0’s behavior;
. You can also trysome curved or slanted walls to see how the Tribot v 1.0 responds; even though the program wasn't designed to handle these situations, it might work just fine; ifnot, think about how you might adjust the program to make it more versatile ;)
I think this pretty much does it on our first attempt to solve this maze using LMS :)
Let me know if you guys have any specific questions or anything and I’ll try to address in the comments section below or at my youtube channel — click here;