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What's the Coolest Thing You've Ever Built?
Josh Lindenmuth asks: "In high school I was involved in an engineering competition where we needed to create a machine that could move 100 lbs of groceries from a disabled person's car up and down a set of stairs, and then into their kitchen. It was probably the coolest thing I ever built (there were only 3 of us on the team), even though the wooden treads started splintering halfway up the stairs (we didn't have a metal shop, so it was made entirely out of wood, spare boat parts, and conveyor belts) and then it completely destroyed the stairs on its way down (it weighed over 300 lbs)." That's Josh's story, now he wants to know yours. Cool computers, cars, hovercraft, handheld devices, fusion reactors — what is the most interesting gadget, product, or device that you've ever built on your own?
Period!
I built a reality simulator. You're living in it right now. Neat, huh?!
There was that one time I built a machine that could propel cats to the moon. It almost worked, too.
One time I made a "Jump to Conclusions" mat. You see, it was this mat that you would put on the floor... and had different conclusions written on it that you could jump to.
I think many /. readers weigh >300lbs, period.
This message printed on 100% post-consumer recycled electrons.
My first semester at UW Madison my Introduction to Engineering class buit a BioDiesel Reactor. It was 18 freshman students who knew nothing about biodiesel, and by the end of the semester we designed and constructed the reactor. I was involved on the team that designed and executed a safety system that monitored the temperatures inside the reactor tank, if the temperatures exceeded 60 degrees celsius a relay shut off the heating element in the reactor. This was one section of a larger lecture, and all other projects pailed in comparison. We also had a $500 budget which we exceeded by $4500, the project was paid for by a department at a technical school in Madison.
Feet tend to distribute wait in a nice, convenient way. That, added to the fact that muscles allow us to slowly descend our feet to contact the step. A 300lbs robot composed of wood, probably does not have this feature. Plus, wood is much harder than flesh (duh). Get a 300lbs pirate with wooden pegs for legs and watch him fuck up your stairs in a few weeks.
With a friend I built and wrote an IM client that worked between two TRS-80 model I computers. We "networked" them together by connecting the tape drives between each other (needed an amplifier), and cross connected the "send" and "receive". Then we wrote software that accepted input, sent it across the tape drive, then listened for a message from the tape drive.
It worked well, but of course was very slow.
Then there's the joystick-controlled typewriter...but that wasn't as cool.
As a freshman in the danish "gymnasium" (which is senior year of high school + 2 years of college), we had
:-)
an project in physics class where we could write about anything we wanted to. As a group of three students
we chose to write about digital logic. In the beginning, we only planned to write about digital logic theory,
circuit design theory, and so on, but we soon realized we wanted to build an actual circuit design.
After spending days or even weeks designing the thing, we finally had our ÜberMachine - we called it the
DALO (Digital Arithmetic and Logic Unit). It was essentially an ALU with support for addition, subtraction,
logic "or", logic "and", and logic "not".
Now, in this day and age of computers, it would take most programmers just a few minutes to make such a program
in most programming languages. But this was done entirely in hardware, with no fancy integrated circuits! We
used about 15 simple chips (classic phillips 74xx-series), which only contains or, and, not and the occasional
full-adder.
For the input, we used manual flip-switches, connected directly to the input legs on the microchips.
For output we used a series of LEDs to output each of the 4 digits in the A-input, B-input and the result. At
the same time, we used a classic 7-segment display for each, driven by a 7-segment-decoder chip.
In the end, the things actually worked, which was quite amazing to see. We hadn't received any formal training
in digital logic, electronics, or circuit design - and yet it worked. The entire machine was soldered with more
wires than I ever wish to see again, and it took a lot of blood, sweat and... time - but we did it!
Some years later, I was employed as a teaching assistant at the university. One of my classes were in machine
architecture, a course which most students couldn't see as relating to reality very much, because they didn't
believe anybody except large companies could build computers or circuits. On the day of my last class, just a
few days prior to the exam, I brought our high school project with me, and showed them how it was built.
Several of them were amazed by it, and it really seemed to make a difference. Computers were no longer magical
devices crafted by dwarven builders, they were simply complex machines, free for anybody to build.
That's the greatest thing I have ever built. Now, if we were talking about programming, that would be
another matter...
With great numbers come great responsibility!
A few months ago, I started learning electronics. My first project is (electronically) complete - it just needs some finishing off to the housing.
It's a Nixie tube display, with 7 nixie tubes. I built an RS-232 reciever/sender out of 4000-series logic ICs (not a CPU or microcontroller in sight) - mostly counters and registers, and a few AND gates and inverters.
Pictures of the project's progress are at http://www.alioth.net/pics/nixies/nixies.html (two pages of photos - the working project is on page 2). I've also kept a journal of building and learning in my Slashdot journal.
The hardest part of it was probably getting the 170 volt switch mode power supply to work correctly (mainly getting it to regulate) and not put so much noise back into the 5 volt supply to cause latches and registers to lose their values. Some help from the NEONIXIE-L group on Yahoo was invaluable here, and I now have a decent 170 volt supply.
I'm now learning how to make things with microprocessors, and once I've done some breadboard experimentation, my next project is to build a logging weather station for the glider club, using a Z80 processor, a flash EPROM, some RAM and probably compact flash for mass storage (not that it'll use a lot of it!), and a small graphics LCD module for display. Currently, I'm at the stage where I've breadboarded a very basic Z80 system that can output values on a crude output device. But it works!
Oolite: Elite-like game. For Mac, Linux and Windows
I don't know, but I'm thinking he'd view his project as much more of a success if he simply re-defined it. Machine for carrying groceries up stairs? No! Automatic Staircase Destroyer? Hell yes!
The enemies of Democracy are
It's designed for use on Amateur Radio frequencies, specifically between 3700-4000 Khz and uses basically the same technology as broadcast transmitters from the early days up to the 1960's.
1 46.htm
Here's a Coral link to it:
http://www.mymorninglight.org.nyud.net:8080/ham/6
The best part about it, is that I built it entirely from stuff that was headed to the scrap heap!
There are other interesting or unusual things I've built, which can be seen by following the links. In one especially unusual project, I used the analog circuits from a fried SoundBlaster card, and a CD drive as a modulator for a tube-based, low-power AM transmitter. Combining 2000's technology with 1950's. It worked, too!
Willie...
Been working on a list of my biggest inventions and intellectual property items that flopped in a big, big way. My coolest inventions and IP flops are:
But my all time coolest thing I have built, and my biggest tech flop, is one I called an abtaser:
Abtaser
Doctors destroy health, lawyers destroy justice, universities destroy knowledge, religion destroys spirituality
I think the coolest thing I ever built (or designed and programmed) was a self-contained turntable system for an automated monorail part transport system. The thing had multiple stop points that could be programmed, automatic homing, and built-in accel/decel ramping. Used a mini handheld pendant to program the stop points - you could literally walk under the thing and see the alignment as you made your adjustments.
To the best of my knowledge, it is still in production at Caterpillar today. It was designed and built in 1998.
The second best coolest thing I ever built was some software for interfacing a Linux based PC to an Allen Bradley ControlLogix PLC. The real cool bit is knowing that this software is being used in multiple production facilities around the world from making baby formula in Canada to being used in a mix simulator for the AirBorne Laser program.
Ron Gage - Westland, MI
I built a 2 tap Kegerator with a tile counter and a computer to weigh the kegs and tell how much beer is left in each keg. Check it out here http://photos.yahoo.com/melendez_21 I also installed a glass door to keep liquor cold with a black light.
I've built a few things I really liked:
1. Building an airplane (200+mph 4 seater version of a Burt Rutan design)
2. Flamethrowers (the response time of the Culver City police department to 40+ foot flame mushroom clouds is 5 minutes)
3. TankCams - I've explored the crawlspace under my house from the comfort of my living room via teleoperation.
4. A couple of neat costumes, this year I was written up on slashdot about my Aliens walking forklift costume.
5. An inertially coupled autopilot for R/C planes I built years ago as a cheap UAV so I could send a plane someplace, take pictures, then have it fly itself back, all without crashing.
There are lots of cool things to do out there, I'll be dead when I stop working on them. Instead of being a "remember that time back when I was held the football record at Polk High" thread, I hope this thread focusses not just on past accomplishments, but also mentions things people are still actively doing, otherwise it'll be terribly depressing.
While I was a Junior/Senior at Everett High School, (Lansing, Michigan), I built a tunneling scanning electron microscope. We originally followed/used a kit from the University of Muenster in Germany that I had learned about from Slashdot. Unfortunately, the documentation sucked, the circuit board was etched incorrectly and there was a design error. Furthermore, the control software was written is visual basic and was nothing more then a toy.
;)) to support accelerated Nanotechnology development and commercialization while also encouraging applied and basic research. Michigan State University and the surrounding universities are home to world class researchers and students working on Nanotechnology and Nano-Biotechnology. It has been decided that it is time the state began to leverage that asset to create a bright 21st century future for our citizens.
With the help of a electrical engineering group at Michigan State University we overcame the problems and I decided to modify the original design to use GXSM, a powerful open source electron microscope software package that is Linux only. This required adding a sranger digital signal processing board and stepping up the input/output voltages for the piezo crystals. Amazingly, almost all the work was done by myself or fellow students, MSU only guided us in understanding the circuit diagrams, making small adjustments, fixing the errors in the plans and designing/building the stepping circuits for my modifications.
I have some really great memories, spending all day in the basement lab I had set up, eating pizza while skipping all my classes with permission from the principal, "accidentally" burning my long time enemy with the soldering iron, ripping a chunk of my finger off jumping a network wiring cage to connect the main computer to the internet.
Working with the electronics and science was very interesting, but the most valuable experience came from lobbying for the funding from local government, assembling a team of fellow students to work on the project and starting a Nanotechnology elective class to actually use the damn thing. Eventually, former State Senator Virg Bernero (now Mayor of Lansing, Michigan) convinced BioPort (the company that makes the Anthrax vaccine) to provide the majority of the funds.
The project eventually inspired local university and government leaders (I wouldn't stop bugging them
I'm 19 years old, and thanks to the Slashdot article "build your own electron microscope" I've actually become something I'm proud of. I've built a tunneling scanning electron microscope, lobbied for funding and government support, founded a Nanotechnology class at Everett High School with help from a amazing science teacher who now is inspiring the class to even greater things while developing a soon to be accredited curriculum, hired as a contract consultant by a company in silicon valley, been sent overseas, all expenses paid to a nanotube conference in Japan by the same company and I now work at M.S.U. as the only employee in a new Nanotechnology supporting office at the college of Engineering. (There is also some other stuff I'm not allowed to speak of.)
I've met very important people from NASA's JPL, IBM, Oxford, Harvard and founders/pioneers of Nanotechnology.
In my free time, I lobby for the creation of a Michigan Institute of Nanotechnology, which will become the center of Nanotechnology in the state, facilitating the cooperation of private industry, research, academia and government to create jobs, businesses, breakthroughs and secure a portion of the world economy for ourselves. It already has a extremely wide and powerful base of support.
Not bad for someone who graduated with a 2.5 GPA.
A couple of years ago I built an air cannon for the purpose of launching mountain lion scat at prey species, as part of my study of prey responses to cues of predation risk. My first test-firing of my dog's turd (using a foam coffee cup sabot) launched it's payload >200 m towards a house on the next street (I hid rather than verify the point of dookie impact). Imagine, if you will, the joy of recreating the primal thrill of monkeys hurling their excrement through the bars -all under the guise of science, of course. Alas, the seals in the sprinkler valves blew out after a dozen firings and I reverted to the low-tech slingshit to complete my experiment. Now if I would just finish writing the Ph.D. instead of posting to slashdot...
Throughout high school, I was forced to do Science Fair projects. I picked MagLev's. I did experiments, wound my own coils, did a bunch of different tests and moved my project along in different phases during freshman to junior years. Senior year I was able to get a mini grant and order from Scientific American for some rare earth magnets. It was not as automated as I liked, but I had built stepping logic and used my own coils to at least show things are possible. If you've been to Epcot there is a demo which was very close to what I built in my senior year. I can't say they were equivalent. I was very depressed once I saw it, but then again I was only 15, and it was Disney, they had all the toys.
Fast forward to college. Senior project and after taking all the courses in logic, programming, processors, etc I then found out what I could use to make my toy work. So, I spoke to my advisor, he loved the idea. I spent that summer winding coils with 26 gauge wire. I made a length of track two feet long and I it used 48 coils. I used sewing machine bobbins as the sizing. I cut a 3/4" pvc pipe so that I could slide in each coil and get to the leads. This gave me four sections of track, each with 12 coils. The coils were wired in series so that we had a pattern ABCABCABCABC. The logic I built would pulse the A group at 12v, the B group at 9v and the C group at 6v. This created a "wave" that would "push" the train in the desired direction. To go the other direction, all you had to do was flip a DPDT relay and switch A with C.
The brains were provided by a Parallax Stamp 2. This thing was great. I could have multiple inputs and outputs to make everything work. I used som buffers to make sure I didnt kill the chip with draw and I used logic to drive transistors that tripped 12v relays for the juice. When working, the train could go one direction or the other, depending on how the coils were energized. Since the track was only 24" long, I used optical led sets to detect where the car was. These inputs were fed into the stamp. Based on direction and track section the car was on, the group of 12 coils were the car left was turned off, and the section the train was about to enter was turned on. Of course, there were always two sections on so if the train was in section 2 going to section 3, then the stamp knew to switch off 1 and turn on 3, leaving 2 running. The car was pulsed slow, so it had time. Was not as smooth as I liked.
Had to use a huge power supply, 12v 30a, tho I think it only used between 8 and 10. I still have it on a shelf behind me. Maybe one day I'll dust it off and see how I can improve on it. It blew away everyone else's project. Once I started the car rolling, it would happily go back and forth all day long. It was stable (temperature wise) and if you ignored the clacking relays, it was fun to watch.
It is not the coolest thing I've ever worked on or designed, but in terms of what I put into it and the fact it was my brainchild, I'm totally thrilled with it to this day.
So there.
Your self are living in one of my own collection of home built reality simulators. I'll give you credit for being the only one of my simulated worlds to develop a reality simulator inside your simulation.
Greetings,
Your Lord and Creator.
P.S. If you think that's strange you should see the 4D Holo-presentation I got the other day attatched to a subspace mail message. It's from a giant lizard like creature who claims that I am living on a planet in a miniature universe he carries in a little marble on his keychain....
Only to idiots, are orders laws.
-- Henning von Tresckow
You work for Microsoft, don't you?
Swedish plasma phys. PhD student; MSc EE; knows maths, programming, electronics; finance interest; seeks opportunities
You missed the major factor - contact surface area. If you've got a polished wood floor, a 120lb woman can very easily damage it in high heels if the surface area of the heel is small. I imagine a 300lb geek dressed as a pirate in high heels would go right through to his parent's basement.
In high school my junior year ('65) I built a system that displayed electromagnetic radiation from lightning strokes on a CRT. I had little money so built it from old TV and surplus parts. Three foot loop antennas oriented N-S and E-W picked up the signals and displayed them on a scope tube. The whole thing was vacuum tubes, I think around 8 or so. That was pretty cool but not all I wanted. The next year, I contacted IBM, who helped me with schematics of flip flops and other logic implemented with transistors (wow!) and I made a recorder that would write the signals on paper charts so I could correlate them with the next day's newspaper reports of distant storms. The recorders were constructed of old speakers with the cones removed but the voice coils still in place, recording pens on long arms that magnified the motion of the voice coil, and a coffee can driven by a clock radio movement that moved a sheet of paper under the pens every 12 hours. I ran it a whole year and tracked storms as far away as Lousiana from my house in Minnesota by the lightning they produced. It was pretty neat. I also tracked some tornadoes that I recognized by the almost continuous lightning they produced. It was lots of fun and I won some awards at the science fair.
It also got me a college scholarship to get into a physics program, which I wouldn't have gotten any other way. So, now you know how I came to be spending my Saturday afternoon typing into Slashdot.
Back in high school I made a really huge bong out of 1 liter soda bottles and aquarium tubing.
You are so boring that when I see you my feet go to sleep.
Like many kids in the 1960s, the coolest thing we could get our hands on was Estes model rocket engines. I particularly loved to make "boost gliders" which were devilishly difficult to build right. They were complex because they had a large rotatable wing. During the boost phase the wing was retracted parallel to the main tube, but after the rocket burned out, the propellant module ejected and the wing would rotate out to a configuration like an aircraft. The idea was that the rocket would shoot upright to maximum altitude, then the wing would deploy and it would fly in a flat spiral, then land close to the launch site. If you did it wrong, it would go up and then fly off in a straight line off to the horizon, never to be seen again.
The best rocket I ever made was a scale model of the BOMARC, one of the first cruise missiles in the US arsenal. I spent weeks making sure every detail was perfect, it looked beautiful, even the paint job was polished to mirror-like perfection (very difficult for a 12 year old kid like me to achieve). The aerodynamics looked good, although scale model kits were notorious for poor flight qualities since sacrifices were made for the sake of accurate design. But I managed to static test the rocket until it worked right, this was done by attaching a long piece of string to the rocket's center of gravity, then whirling it around at the end of 20 feet of string, watching its flight dynamics until you puked from dizziness. A little trim balancing here, a little added weight there, and everything was perfect.
In fact, so perfect I didn't want to launch it. I hung the rocket from my bedroom ceiling, where I fondly gazed at it every night as I lay in bed. Eventually I decided I had to see it fly. But to minimize the risk, the first flight would be a small rocket engine, I didn't want to shoot it up 2000 feet and maybe never see it again, a small 200ft flight would be sufficient. Whenever I set up my launch pad, all the neighborhood kids would suddenly show up to watch the launch. 3..2..1.. blastoff! It popped up, the engine ejected, and the BOMARC flew in a perfect spiral about one block in diameter. All the kids started chasing after it, back and forth, as it lazily spiraled around up out of their reach, I laughed and laughed. I stood right by the launch pad as the rocket started coming down, it looked like it would land almost at my feet.. and it DID! And then one of the kids chasing it STOMPED right on top of it, smashing my beautiful rocket to bits! Dammit!
I think I gave up building rockets after that, my heart wasn't in it anymore.
Oh yeah.. I do recall building one cool rocket, once I was an adult. I found out that ultra high performance engines had come on the market, I think this was the late 1970s. No more wimpy Estes D engines, these were E, F and G engines. I heard there was a 2 stage rocket kit that would break the sound barrier, so I ordered one. IIRC, it was a G engine with a D on top of it. No sense in buying more than one set of engines, this kit would go up thousands of feet and come down miles away, I'd never see it again. The fins were made of composite balsa plywood, regular plywood would just break apart when it hit the sound barrier. The fins had to be epoxied carefully to the body tube with perfect fillets, construction details were crucial, the kit instructions said that the slightest flaw would cause the rocket to break up and smash INTO the sound barrier, rather than through it. It also recommended not painting the rocket as the least imbalance (i.e. more paint on one side than the other) would have an adverse effect.
So I built the rocket, and my friends got together so we could launch it. We had to find a big field because you were supposed to stand at a specific distance away (~250 ft IIRC) so you'd be in the right spot to hear the faint sonic boom. We brought a long tape measure to mark off the distance precisely. I only had 20 feet of wire to run to the electronic igniter, so we drew straws on who would launch, the poor sap who pressed the button woul
That reminds me of a joke:
A scientist goes to God and says, "We don't need you anymore. I can create a human from nothing more than a handful of dust."
"Alright then, let's see," God replies.
"No problem," says the scientist, and he bends over to scoop up some dust.
"Hold on," God interrupts. "Get your own dust."
This space intentionally left blank.
When I was in high school, I built some parts for the temperature regulation system of the AMSAT Phase 3D satellite. 288 tiny aluminum parts, each about 2cm long, and 0.1mm tolerance on all measurements. We used the school's CNC milling machine, but I had to hand-write the CNC code to do the parts in four passes, because the CAD/CAM software wasn't up to it. We then we hand-polished the parts to get them within tolerance where possible. The satellite is still in orbit, it shows up in J-Track as Oscar 40, but apparently it doesn't work anymore.