Here in the Bay Area, the Space Shuttle Endeavour did a victory lap, passing over Sacramento, the Golden Gate and many other Bay Area locations. Pixar Animation Studios is in Emeryville, quite close to the Bay Bridge, so I thought we had a pretty good chance of getting a good view. Sadly, all my good camera gear was stolen in our recent burglary, so all I had was my trusty iPad. I positioned myself along with lots of others out in the soccer field, and we caught this (not particularly amazing, but still impressive) view of Endeavour and it’s chase plane heading out toward the Golden Gate.
Fellow Pixarian Chris Walker was apparently at the Alameda Air Station with a better camera, and got much better results.
Endeavour was constructed as the replacement for the Challenger, and flew 25 missions into space, amassing 299 days of flight time in orbit. While digging around, I found this rare glimpse of it docked with the International Space Station, photographed from a departing Soyuz capsule.
Endeavour will find it’s final rest at the California Science Center in Exposition Park in Los Angeles. I’ll have to go have a closer look when it’s installed. Very cool.
But I figured you guys might like some additional details. As I mentioned before, I decided to build a clone of the Axon, a nice light FPV platform designed by Ed of Experimental Airlines. It’s a neat little plane, and is in many respects very similar to the Easy Star. It has a pusher prop mounted near the middle, a 55″ wingspan, and is about 42″ long. It’s constructed out of foam board tubes for the body, bonded together with mounting tape and a little Duct Tape. The wing’s are a pair of Armin wings (see Ed’s videos for instructions on how to make them) and have a 5″ chord with 1.5″ elevators. I have ordered the motor, ESC, and batteries needed to get it into the air, as well as a 5.8ghz video link setup and camera. Most of those items are back ordered, so it might be a while before this thing gets into the air, but I think it looks good so far. You could probably build one in a single weekend without any sweat.
For reasons which continue to escape me, Mark decided to let me try to take up another of his planes this morning. Last week, I took his EzFly up, with the net result of a mangled prop (which caused the heavy vibration in last week’s video) a cracked wing (repaired with Foam Tack, good as new) and a divot out of the prop slot. Oh well. This week, he let me take up attempt to wreck his Easy Star. I managed to have almost ten minutes of flight before it got significantly downrange, and I got confused about the orientation against the bright cloud cover, and I put it in the ground.
The EasyStar is a pretty nice plane, with a 6″ prop configured in as a pusher. It’s got a nice bay to hold batteries etc… and we velcro’d my $8 keychain video camera onto the top surface, with a slight downward angle so we would mostly be looking toward the ground even in level flight. The overall proportions are remarkably similar to the proportions of Experimental Airlines Axon that I’m currently working toward scratch building, so I thought it would be a good training session for my ultimate goal of flying something I built. The Easy Star has a typical three channel rudder/elevator/throttle setup, unlike the EzFly that I did last week, which had elevon control. I found the feel to be a bit different: the EzFly’s greater dihedral made it self level, and I found the elevon control a little easier to get the hang of. Still, I did rather well, right up until…
I let the plane get fairly far downrange, and I suffered a classic case of perspective reversal. I thought it was coming at me, when it was in fact going away. I got the thing too far out of level trying to turn, and couldn’t recover. I bonked it into the ground (a considerable distance away). The hatch and camera both popped off, no big deal, but I also had a minor stabilizer issue:
Mark was quite gracious, and assured me a quick repair with some Foam Tack would render it “good as new”. But when I returned, I priced a replacement: $12. I think Mark gets to have lunch on me sometime in the near future. I’m also thinking that I’m going to make a duplicate of the Axon for him, just because he’s been so patient with me.
In any case, we did recover the camera and video, and it does show some nice views. Before you watch the video, you might want to turn down the sound. But it should be noted that I did actually cut the motor entirely in spots, and just glided around. All you hear is just the wind noise. Pretty neat.
A view of the Berkeley Marina
Mark H (on the right) and myself (left) viewed from the plane
Early on Sunday I was out at Home Depot and acquired some additional raw materials for my RC plane construction projects. I got a 4×8 foot sheet of 0.5″ pink foam, a 36″ chunk of 2″ angle iron, and a new 4 foot steel ruler (I know I had one somewhere, but darned if I could find it.) Anyway, after my experiment with making a square box fuselage, I thought I would try making a wing with an “Armin” wing, as shown in the YouTube videos of Experimental Airlines.
It took me about 10 minutes to put together this 30″ wing, with a 6″ chord.
This is the simplified version of the wing, which has a trailing edge which is two thickness of foam board, and does not include an integrated elevator. The construction followed these directions almost entirely:
I didn’t get the tape down as smoothly as might have been hoped, but it still looks pretty good. I’ll next try the improved version with the tapered trailing edge, and maybe a carbon arrowshaft stiffener (although this wing seems plenty strong.)
I was feeling pretty lazy today, but I still wanted to do something working toward an eventual new scratchbuilt RC plane project. I’ve been watching a lot of stuff on YouTube, most notably the videos by the Joshes at flitetest and the great YouTube channel of Experimental Airlines. Experimental Airlines seems especially great: he makes some very interesting planes using a variety of neat techniques, made mostly from Dollar Tree foamboard and clear packing tape.
So, I decided to try to make a section of this fuselage, just as a test. I had some clear packing tape lying around, so I layed down about a foot of it on one side, not nearly as carefully as he does, but I was doing this in my living room while watching TV, and the light wasn’t really as good as it should be. I then followed his directions, although again with perhaps a bit more haste than I should have. I had some difficulty getting the final glue joint to really lay down flat, I think if I had some angle iron and some clamps, it would have helped. Still, another layer of packing tape laid along the bottom made an entirely serviceable, sturdy tube.
A finished twenty inch section of tubing.
The end view, with the reinforcing inner gusset.
I have a piece of iron angle iron which would have worked nice as an interior clamp, but it was dirty and rather oily, so until I can clean it and wipe it down, this will have to do. I doubt I’ll use this directly in a plane, but it was good practice (and cheap, since Dollar Tree foam costs a dollar). I suspect next time I’ll get the final joint better. He also has another method, which uses Gorilla Glue, which for this application might be easier to manage. I might try that out soon.
Stay tuned for an actual airplane construction project.
Mark H. over at Eastbay RC and I finally got together to test out my first attempt at scratch building a radio controlled aircraft: an F-22 inspired “foamie”, which an aircraft constructed entirely from EPP foam, hot glue, a couple of short carbon fiber rods to stiffen, and hot glue. Did I mention the hot glue?
Last Friday, we tried to get out to Cesar Chavez park near the Berkeley Marina and fly, but unlike the great weather early in the week, Friday had strong winds and a bit of rain. Mark got his F-22 up in the air for a couple of flights, but mine suffered a glue failure on one of the control horns, and it did not make it into the sky.
But this Wednesday, we did manage to get some better weather. While overcast, it was nice and still. It should be said at this point that I’ve never flown an RC aircraft before, and for my first construction project, I could have chosen a better plane (although I think it looks cool, and that’s what counts!). Thus, I let Mark and his experience man the controls, hoping that even if the plane was poorly balanced or constructed, he’d be able to get a couple of flights from it before it fell apart and its organs harvested for a future aircraft. I was thus mostly a spectator, and shot some video with my iPhone. Due to poor planning, I didn’t have a lot of space left on the iPhone, so I only got the first part of its maiden flight. We actually sent it up several times, and included a couple of flights where we taped my $8 keychain video camera to the nose. I stitched this video together from both the iPhone footage, as well as the nose cam footage. Not too bad for my very first foray into RC construction.
Mark wasn’t about to let me get away without at least giving a try at flying. He felt (and I agreed) that perhaps my airplane wouldn’t be the best plane to start with. In a fit of generosity, he let me take the controls of his own EzFly, a much more forgiving slow trainer type aircraft. It’s a great little plane, which has a KFM style wing, some dihedral to keep it level, and a nose consisting of three layers of foam for maximum energy absorbing capability. My first flight was good evidence that perhaps this trainer was a good idea. After a relatively smooth takeoff, I cartwheeled it into the ground, causing it some injury. But with some quick repairs (blue masking tape) it was ready to fly again. I did a few more flights, and quickly improved. For my last flight, we taped on the nose camera again, and I sent it into a high soaring flight.
Sadly, the video during the ascent when the motor was under full power exhibited an odd distortion caused by the vibration beating against the rolling shutter of the cheap camera. But when I cut the motor and started coasting down, the video was pretty cool. I have a rough unedited version below, sorry for the 40 seconds of mark setting up his iPhone to record me flying. (Warning: there is audio on this one, be prepared for motor whining!)
Not bad for a first outing. I think that the F-22 will remain until I get a little more experience in flying. Mark’s EzFly impressed me so much, I think I’ll have to construct one of my own (Mark has already muttered about splitting an order of some more sheet foam, I’m in!). We might try to figure out why the vibration on the EzFly seemed so much stronger than the vibration on the F-22. The high soaring flight of the EzFly was really nice, and once I got the hang of being gentle on the rudder and ignoring the elevators entirely (use throttle to go up and down) it was almost relaxing to fly.
If you’ve ever wanted to get into RC, it seems like this kind of construction and all the great online resources have never made it easier (and it doesn’t hurt to have a patient and more experienced friend to help you.) I’m hooked. Expect some future planes and flights (perhaps better documented than this build).
Addendum: While investigating the vibration issue, I found a number of other vids which demonstrate the effect, although none perhaps as severe as the one I saw. Someone suggested that we might have been running with an unbalanced prop: given that I had mashed this thing into the ground, it’s entirely possible that I bent it up. But during my investigation, I found this extremely nice video of a wing mounted camera on a gorgeous looking P-51. For your viewing pleasure:
I received my second email inquiry yesterday (yes, two whole emails) asking me why I hadn’t been posting to brainwagon lately. It’s gratifying that both of my readers would each send me a note asking if things were all right, so I thought rather than addressing you each separately, I could double my efficiency by creating a post.
There are many reasons for my apparent slowdown in posting. My new project at work is taking up more time. I haven’t done much amateur radio lately, mostly because I need to rework my antennas (I want a more permanent way to route coax inside, rather than just “opening a window”), and the programming muse has seemingly left me: I can’t seem to muster a lot of enthusiasm for it at the moment.
These would by themselves normally be enough to slow me down, and perhaps bring a temporary halt to blog posts. But there is another reason: the unavoidable drone of the election season.
You see, I’m a person of fairly strong political convictions, and the election season always presents enough fodder that daily I find myself yelling at the television. My temptation in moments of weakess is to turn these diatribes (well founded as I believe them to be) into blog posts, but I don’t think that my readers (both of you) come to brainwagon to read my political positions. If I invited you to my house for a barbecue, I’d be a terrible host if I simultaneously subjected you to rants on the subject of politics or religion. I view brainwagon as a place where I can talk about interesting things of little consequence. I’m going to try to keep it that way.
On the brighter side: some cool projects are underway. The F-22 RC airplane I began several weeks ago is mostly completed. With the help of Mark Harrison of Eastbay RC, I had the thing entirely assembled, and we were set for a trial flight on Friday, but sadly after a week of beautiful weather, Friday dawned cold, with a light drizzle and strong gusty winds. We might have braved it, but I noticed at the last minute an issue with a loose control horn on the elevon, and it would not have been controllable. It needed a return to the workbench for a fix.
When I got back home, I pondered another problem that I had with my assembly, if you check out the following video, note the placement of the servos:
Did you see the issue? the servos are mounted very near the slot where the propeller will be mounted. In fact, when the elevons are in the down position, the little control arm for the servo comes uncomfortably close to the propeller. I decided that while I was fixing one of the control horns, it would be good if I unglued the servos and mounted them further back.
And here’s where having a great mentor like Mark really helps: he informed me that isopropyl alcohol applied to the glue joint would wick in, and I’d be able to peel the glue off. A trip to Walgreens and $2 got me a nice bottle of 91%, which I applied with a cotton swab. A few minutes of waiting, a little wiggle, and the servos popped right off. A little more alcohol applied, and I was able to peel the remnants off the foam and the servo. Very cute.
Today, I hope to get the new, shorter control arms in place, with better control rods in place, with hopefully less flexure. Then, the question will be: dare I try it out? I actually have no experience at all with RC planes: I was going to rely on Mark to help me get it off the ground and maybe avoid a crash by using “trainer mode” on my transmitter (enabling him to take over and fly). I probably shouldn’t have begun with the F-22. Something with some dihedral and maybe even a real airfoil so it can glide in without power would be better for a beginner, but it looks really cool. 🙂 I expect that after two or three flights, it will be in such bad shape I’ll have to harvest its organs for use in another plane. But I will have learned alot.
I’ve already begun to plan a second plane, and to acquire the parts for it (whatever it turns out to be). Ultimately, I’d like to get to the whole FPV (first person video) setup, and be able to fly with cameras aboard, but I think until I gain some experience, it would be pointless (or even counterproductive) to spend lots of money on equipment. After all, you have to walk before you can run.
But I did find an interesting gadget that’s a baby step in that direction: an $8 Turnigy keychain video camera. It records MP4 video at 640×480 resolution onto a microSD card (not provided). I had a 4GB class 4 card, which worked okay for early testing, but it seemed like it had a problem maintaining full frame rate with that, so I ordered a couple of nice little Class 10 cards from Amazon, and they seemed to work out very well. Since my plane isn’t ready for flight testing, I decided to test the camera by velcroing it to the license plate holder on my car, and taking it for a short 15 minute drive. I then took the video and post processed it with ffmpeg to turn it into a time lapse video (25x faster) and got this result:
The overall clarity is not bad: the automatic exposures can sometimes lower contrast and wash out the image, but perhaps less than I might have expected. The biggest problem I suspect I’ll have is that the field of view is quite narrow, and thus when mounted on the airplane, may jerk around a lot. But for a total investment of around $17, it’s perhaps better than I might expect.
Stay tuned for more, and thanks for your patience!
