8 replies to this topic

[Zero Talent]

Well, for my application to the University of British Columbia's Mechatronics (Electromechanical Engineering) program, I was asked to compile a portfolio of any and all relevant design experience. Any of you here who know me well may also know that I have little electronic aptitude, and thus I had to rely on past mechanical designs. I'm sure they don't expect too much from us; A lot of my peers only have website design and the odd lark to display.
So -- you guessed it -- I had to fall back on Nerf. I tried to sort of expand on the fact that I've been designing silly systems like this for almost 8 years now:

http://www.geocities.../EYlauncher.txtHee hee...

And followed up with airguns and such that I've built. [Tried to sort of downplay the leitmotif of "guns," though it was quite, quite challenging. ]
I can only hope this helps me... My grades are less than fantastic, and this program is pretty much why I applied to UBC..

However, this can't be a topic about me. Rather, I'd like to ask you guys if your experience with Nerf ever lead to anything externally useful. Sure, there's always the garnered knowledge from applied design, but anything related to your official education/career?

Or, better yet, has the reverse happened? I'll refer to Boltsniper as an archetype, though it can encompass any kind of involvement.

[Ice Nine]

I'm not really sure what that drawing is...

... But right now Bobert and I plan to make a soap-box derby car from PVC, with an RF20 in the fron that you can fire by pressing a button. And has holsters to hold other guns. Yes, I know how to make the RF20 fire at the push of a button.

Yeah, I have everything written up in my math work somewhere, so when that's done, I'll alert everyone.

<edit> Ah, a snowball gun it is! Interesting, interesting, although I live in L.A. and only see snow twice a year. Seems cool. </edit>

Edited by Ice Nine, 31 March 2004 - 09:21 AM.

[boltsniper]

Zero Talent, on Mar 30 2004, 08:26 AM, said:

I'll refer to Boltsniper as an archetype...

Heh heh...

I`m not sure if I know what that is a drawing of either to be honest. Looks like some kind of snowball launcher ot something of that order.

Zero, you should offer as much info about everything you do in you personal life that pertains to engineering towards your admission to college. The display of knowledge and the ability to apply it can far exceed grades and test scores in recruiteres eyes.

When I applied to Virginia Tech I created a portfolio, so to speak, of the personal projects I had done through high school. These includedmy experience with R/C aircraft with which I had built and flew a couple of my own design. I wish I had some pictures of hese on hand to show you. One was a conventional design while the other was a pretty radical canard design with the canard being forward swept and overlapped the aft swept wing. It was sweet looking and I miss it greatly. It flew like a dream but it took a fatal nose dive into the ground after a battery failure. I was so pissed. I also built an audio amplifier from scratch in high school. You can see some pics of it here I wanted a small, high fidelity amp with tone controls that I could use with my portable CD player. I couldn`t find what I wanted to buy so I built it. It has twin 30W low noise amp and a 4W preamp with treble, bass, balance, and volume controls. The actual amps are just IC's and I had to design and etch the printed circuit boards. The 3 boards along with a giant 25 amp transformer are crammed in a 6" by 6" by 3" project box. As you can see there is no extra room. The sounds quality is incredible and I useit almost everyday to listen to CD's

Coming out of college my grades weren`t stellar so I milked my personal work to get in to grad school. On top of the amp I milked 2 main projects I had going. For my senior project of designing a expendable UAV, I was the configuration designer. Meaning it was my job to actually design the shape of the aircraft and to do all of the CAD drawings. For the drawings I chose to use Unigraphics which is debatably the hardest 3D modelling program to use. People told me it would take weeks to learn and I would have to take a class. I came back the next day with a fully rendered model of our plane having only sat in front of the computer and played around with the program. You can see our project and all my drawings here. Senior year one of my professors sparked my interest in oblique flying wings. an oblique wing is a straight wing that is yawed to one side, ie one tip is ahead of the other. They have some very distinct advantages when it comes to transonic flight but being assymetric makes them a bitch to control. On my own I designed and built two R/C oblique flying wings. I used a lot of industry based CFD codes and design procedures. I got some serious props for this and I beleive this is what ultimately got me into grad school. I am now doing some funded research on the control system for oblique flying wings. I made a simple website showing both models. Here.


As for as Nerf, I was asked several times about the bolt-action rifle. I never presented it but people linked to it through my website. Although a bit confused to the motive (heh heh) they were very impressed. I even had the head of the mechanical engineering department at Tech ask to see it. He was so awe stricken he asked for some plans so he could build one (this is a 50 year old man mind you). I still need to get around to officially drawing those up. Beleive it or not I didn`t apply much knowledge from schooling to the rifle. The only thing I really analyzed was the fluid dynamics of the barrel. The thing that really helped was all the experience I've had in fabrication. It was ultimately the ability to design, analyze, apply, fabricate, troubleshoot, and modify that made me stand out from the others. So many people can do the book work, but when it comes to application they are like monkeys reading a roadmap.

I would recommend that you present as much of the work that you have done personally as you can. Even the little stuff. The fact that you are asked to doa portfolio makes it even easier. Your valve designs with the accomaning website and CAD drawings make that stuff golden material. I`m sure with your work you will have no problem getting in. Good Luck

[Zero Talent]

And I have to compete with people like you...

Thanks for the words of encouragement.. I threw in sort of a chronological setup to emphasize the fact that I've been designing various kinds of crap for years (most of the early stuff was impractical and fictional, but there were odd things, like that snowball launcher [you correctly identified] in grade 6, and this really poorly designed sled)... Long story short, the only good/dynamic stuff I have is in Nerf, so I'm a bit worried the board will think I'm a gun nut, violent, or some other otherwise undesirable trait.

..Feh. I didn't really go into detail about many of the airgun/valve designs, since I assume they're pretty simple (and the big "Semi-automatic Valve" title in the upper right is a dead giveaway), and do not wish to waste the board's time with their simple mechanics until the interview.

I included "Nerf Blaster Mods" as a sort of segue, just to fit the chronology of the theme, with pics of original blasters and their modded avatars, but in retrospect that doesn't really belong in a design portfolio. I'll have to think about cutting that one. The clincher is present-day designs. I have little to actually display, what with being a busy commuter, so all I could put up were my relatively old plans for an air actuated bolt-action breech and a air-actuated blow-back facsimile launcher. You know, this:

http://www.geocities...fied/Breech.txt

...And this:

http://www.geocities...ed/ugliness.txt

..Which I plan to complete in the summer with a wad of other things.

I'll just have to pray my 81.8% Term 1 average carries me through the rest of the way. Or that my competitors only have blogsites in their background.

Meanwhile, that oblique wing design is really interesting... I'll be sure to research why it's better for transonic flight... Does the pressure wave it creates move as a cascade with that kind of wing shape?
But the better question is how you test that R/C flying wing... I understand you're a good aerospace engineer, but I can't see transonic speeds from a small electric motor.

Edited by Zero Talent, 30 March 2004 - 10:59 PM.

[boltsniper]

Zero Talent, on Mar 31 2004, 03:55 AM, said:

Meanwhile, that oblique wing design is really interesting... I'll be sure to research why it's better for transonic flight... Does the pressure wave it creates move as a cascade with that kind of wing shape?
But the better question is how you test that R/C flying wing... I understand you're a good aerospace engineer, but I can't see transonic speeds from a small electric motor.

The models don`t fly anywhere close to the transonic region. The electric model flies maybe 15 mph and te larger gas model flies up around 60 mph. Even though small the dynamic scaling actually provides some pretty good predictions on how a larger aircraft would perform. The models weren`t meant to investigate the transonic performance but rather to prove that a oblique flying wing could be controlled in flight. If you looked at the website at all I`m sure you noticed the placemtn of the control surfaces. There are two surfaces shifted spanwise towards the forwards swept portion about 20%. I did a lot of computational work and glider testing to come up with that. It looks and sounds so bizarre that I double checked my work about 10 times. it wasn`t until I actually saw it work on a glider that I knew it would work. The assymmetric planform causes some quite severe roll-pitch coupling. Offsetting the control surfaces accounts for this.

OFW's exhibit minimum wave drag through the transonic region when compared to other wing planforms. Techinically this is because an oblique flying wing is a mixture of a Sers-Haack boday and a Kármán ogive body, both of which are minimum wave drag bodies of revolution. Physically OFW's have little to no cross flow shocks which are a big contributor in the wave drag rise. The wing for this can not be untapered and most analysis is done with an elliptic planform for maximum lift efficiency.

[Hunter]

Humm...
Very interesting physics, very true also.

By the way boltsniper....
You are a god...
Your rifle is beautiful..

Edited by Hunter, 30 March 2004 - 11:52 PM.

[Ice Nine]

I forgot that you went into the aerospace bussiness, Bolty. What company do you work for?
After college and a few other things, I'd love to work at Lockheed Martin or Boeing or Northrop Grumman as an aerodynamicist and/or engineer. I have already done some work in aerodynamics, as my county scinece fair project is about the aerodynamics of different wing shapes. (Not suprisingly, the one that did the best was the teardrop with the round end forward.) I also love making my own designs of aircraft, and a few of them I think are fairly promising and interesting, such as the one with one double delta wing placed atop the fuselage and another of the same sized under it. With a canard wing in the front.

I'm also interested in FSW, like that Grumman X-29. It woud be very interesting to see how that would perform in a dogfight against, say, a Raptor, or JSF.

Any plane that tries something new (FSW, my designs, etc.) I find really cool, and my favorite type of aircraft are the X-Planes. I like to figure out what was wrong with them, like with the XB-70, which turned out to be Soviet SAMs, astronomical fuel prices, and that civilian test pilot who crashed his F-104 Starfighter into it. That aircraft had one of the sleekest shapes I have ever seen.

Flying wings are cool, except when its the actual "Flying Wing" flying wing. That thing didn't work AT ALL. Altough Northrop finally hit one their success with the B-2, its too bad so few were bought. Those are some amazing machines.

</rant>

<edit> Do you have any pictures of your oblique flying wing? I'd enjoy seeing it. </edit>

<edit of the edit> Nevermind, I saw the link. Cool stuff, although I can see how tough it must be to control that thing in flight... </edit of the edit>

Edited by Ice Nine, 31 March 2004 - 10:14 AM.

[boltsniper]

The XB-70 was a magnificant aircraft and it is a real shame it fell victim to goevernment cancellation and budget cuts. The rapid increase in surface-to-air missle performance is the reason the program was cancelled but it has no relfection on the aircraft itself. ICBM's were gaining enough range and accuracy to strike any city in the world which negated the need for strategic nuclear bombers. Upon cancellation the XB-70 program was completely dedicated to high speed research. 3 aircraft were planned each building on the knowledge gained from the previous aircraft. AV2 had solved almost all of the problems suffered in AV1 and was a far superior aircraft. AV1 had been restricted to flight below Mach 2.5 due to some skin separation problems. AV2 went on to reach the final mission goal of Mach 3 for sustained periods of timeand collected some extremely valuable data. It seems ironic to me that the aircraft was lost during a photo shoot for GE. As the camera aircraft requested a tightening of the formation, the massive vortices that shed off the leading edge of the highly swept Valkyrie wing grabbed Walker's little F-104 and literally threw it across the Valkyrie's back taking out both vertical fins. The XB-70 flew on for a while before departing into an unrecoverable spin to the ground. AV1 is on display at the Airforce Museum in Dayton Ohio. If you have never been than I suggest that you make the trip. It is hard to beleive that such an aircraft was designed in the early 60's with merely wind tunnel data and computers with less power than your calculator. The XB-70 is by far one of my favorite aircraft.


Anyway, I don`t want to hijack Zero's thread here. Come on people, what have you all done besides Nerf oriented projects. There has to be at least one project that doesn`t involve Nerf. Post it here!

[xedice]

I live about 5 minutes away from Dayton Ohio, and have been to the aircraft Museum to see that plane, and several other interesting ones many times. Pretty cool stuff to look at.

Back on topic.. currently, I am spending some time using compressed air to run an engine. First I used legos to create an engine, it ran rough and didn't have enough compress air to last more than a few seconds. So I am thinking of designs that use pvc, brass, and other easily obtainable parts for a better engine. The project is extremely tough, and I don't see myself getting done with it anytime soon. But, tt all stemmed from my interest in air powered guns (mainly nerf).

Edited by xedice, 02 April 2004 - 03:45 PM.