FPV, first and second tries

Okay, FPV is not as easy as it looks.  Or at least not with the Hubsan X4 H107D.  I, like any FPV dreamer who has spent too many hours on YouTube, have dreamed the dream of soaring among the clouds, swooping between trees, following riverbeds, all with the smooth grace of an eagle.  I think grasshopper might be a better choice than an eagle, in this case.  Now, keep in mind that I am new, and this doesn't fairly reflect on Hubsan or the X4 FPV.

So, yesterday I took the new X4 FPV (hereafter dubbed the Grasshopper) out and burned through my five batteries.  It flew as easy as Little Red and is a pure joy out on the open field.  I'm thrilled with the new controller.  The movement in the sticks feels a little smoother than the H104C controller, and doesn't feel as much like a game controller.  I rarely have time, so far, to look down at the screen while flying, but I love the fact that I can see battery statistics and elapsed time since power-on.  Now I can see how long my batteries are lasting without having to start the stopwatch on my phone.  The only downside with the controller is that it has chewed up a set of AA batteries in 90 minutes (yes, barely 48 hours since I bought it, and have clocked about 90 minutes of flight with it).  The old controller has a lot more than that on it and the battery bar for the transmitter hasn't moved off of full yet.  But that's to be expected with a color display running on batteries.

So, back to the flying.  Yesterday I went out and put my five batteries through the Grasshopper and discovered that flying FPV with the Hubsan isn't what I'd dreamed.  At least not yet.  What I did see, as I was zipping around the field, was the grass flying by underneath.  That's about all I could really see.  Either I kept the Grasshopper low and steady and watching grass blades whizzing by, or I got up high enough to see landmarks, and felt at risk of loosing track of it.  Also, the range wasn't what I expected.  50, 60 meters and I was getting static on the screen.  

But wait, the goggles!  That'll make things better!  Meh... I spent more time peering over the top of the goggles trying to keep track of where the Grasshopper was than actually watching the screens.  The screens inside the goggles are nice (at least to me, who has never tried a pair of VR glasses, Google glasses or any other close-view device other than my old DVR).  But they are fun.  And I get to look like Geordie LaForge (or so I like to think), so that's always a plus. "Engineering to Bridge, we've got an imminent warp core brea-- hold on, too much altitude, let me get back down to ... so, then a little yaw, back to me, right,  where was I? Right. Warp core breach!"  So after about two minutes of FPV I took a break from it for the night and burned up the rest of my batteries line-of-sight.  I think the H107D would be a little more FPV-friendly if the camera weren't angled slightly down already from the beginning.  Any forward motion to speak of and the camera is angled so far down that you can't see where you're going if you aren't above 15 meters or so (any tips, advice and correction are more than welcome in the comments!).

Today I tried again and made a lot of progress.  What I did, after a couple of batteries worth of zipping up and down the field and sweeping banked turns past the trees, was to try the FPV goggles again.  This time I took it low and slow and easy.  I powered up the transmitter, powered up the Grasshopper, donned the goggles, took off and just satisfied myself with trying to keep a hover.  I still climbed a lot and had to sneak peeks here and there to see how high I was, but I finally figured out how to get the knack of this:   I backed up and lowered my hover until I could see my toolbox/carry-case/launch pad through the goggles and just tried to hold steady.  Once I felt I had a good hover and kept track of my landmark I backed up more and climbed a meter or so, then dared to sweep S-L-O-W-L-Y to the left, then to the right, and back again, keeping the landmark in sight.  It wasn't sweeping down riverbeds, but it was good training.  After a minute or so of this I felt comfortable with controlling the Grasshopper without line-of-sight on it.  I think this is what it is all about, or at least at this stage of my learning.  So I ran out the last of my battery doing just this, practicing to hover and slowly move while in FPV.  And I'm totally, completely hooked, riverbeds and mountaintops or not!

FPV way ahead of schedule

So, did I mention that I have an amazing wife?  Okay, pretty much once per post, but it's true.  Why this time?  Well, long story short (long story involving Luna sandals and a crocodile (Not making this up.  Don't ask)) she said I really should go get the Hubsan with FPV (Being the Hubsan X4 H107D) PLUS the goggles.  For real.  This is probably a year ahead of schedule.  I was kind of dreaming and imagining a christmas/birthday present.  But ... well, just wow.

Once again, battery in the car charger on the way home, switch over the batteries from Little Red, load it all up, and wait for the kids to get in bed.  Once they were down I was out with my new FPV Quad.  It was already getting fairly dark (yes, even here in Sweden, around mid-summer) so I only put two batteries through it, and the FPV was pretty murky.  I'll fly more tomorrow and get a better feel for it, but for now, suffice it to say: YES!

Training in the wind

Today was a half-day at work.  It's a rare occasion to quit working at noon, now-a-days, so when the chance to get in a mid-day training pass, I took it.  I was a little hesitant, and actually wasted probably an hour, wondering if I dared go out, as not only the trees outside the house were blowing, but so were the lamp posts.  My wife urged me to go out anyway, saying that I might as well learn to fly in the wind (gotta love her :)  )

Sooo, down to the workshop, grabbed Little Red (including four freshly charged batteries) and up to the field.  It didn't seem to be as windy up there, but it was definitely windy.  Not sure what the mph or m/s it was, but it was ... gusty.  Surprisingly, Little Red flew quite well into the wind.  I tried to keep him below five meters or so, but there were a few times he climbed right up there.  When he did, he started to get carried away by the wind, but I managed to bring him back to an overhead hover and coax him back down to the ground.  It took expert mode a couple of times, to get that extra umph.  And of course, once I was in expert mode, why go back?  I'm getting used to the extra zip.

Speaking of which, I got some nice speed passes back and forth across the field with wide, swooping banks.  I'm starting to feel more and more comfortable with my flying.  Though of course far from expert, or even adept.  I'm still at the novice stage, despite the occasional succeeded banking pass.  And my figure eights tend to look more like figure-bowling-pins as while I get a swooping right-hand bank to work, I swing around into the left-hand side and give it too much yaw and almost spin it on its axis.  But I'm getting there.

Had a couple of mechanical issues today.  The first was my own fault as I flew in too close to the wind-breaking bushes at the edge of the field, lost orientation and chewed up a prop and tossing another.  The one that tossed flew off like a maple-seed in two subsequent flights when I made a sudden turn, so the second time if flew off I didn't bother looking too hard for it again and just replaced it.

The other mechanical issue was with batteries.  My first battery lasted around six and a half minutes.  The second went dead after three and a half (on an upside down landing), the fourth died after a minute and a half (also forward tumble) and the fourth lasted over seven minutes.  I put the second one back in and got another three minutes or so and the third went back in and gave me another few minutes.  So I think the upside down landings shorted something out and gave me a low-battery indication (flashing and no throttle).  I'll have to look into that.

All in all, a good training.  And with a little luck, I may even get a second training pass in this evening.  We'll see!

Up up and away!

So with Little Red fit as a fiddle and my lesson learned about flying in the back yard over asphalt I took the chance last night to flight in calm sunset weather up at a little field on the north side of town.  This field is a lot larger and gives me room to move.  Now, what that really means is that I've got more room to make even bigger mistakes.

I powered up, bound up, spun up and trimmed up.  I got used to the hover again, this really being only my second flight outside the workshop.  I started again with back and forth, side to side, get control again, bring it back, crash into the grass, run and get it, rinse and repeat as needed.  All was going well.  So here is where I should write that I learned from my mistake from the first flight and kept things low and slow and under control.  But.... like I said: I've got more room to make even bigger mistakes.

So I figure I am out in the wide open with lots of room around, I can get some altitude and see what it looks like from up there.  I brought Little Red home, turned on the camera and sent him back up.  And up.  And up.  And ... hrrmmm, he sure is drifting, gah, that was rudder, not aileron, no, don't panic,  no not that way, this way, THIS WAY.  Little Red soared higher and off to the west over nearby 8-foor apartment buildings.  Did I say over?  Run, try to regain visual contact, ease down on throttle ... PRAY he isn't right over the top of an apartment building .... throttle's full off.  Okay, for better or worse, he is down.  I ran through the breezeway to the other side of the tall buildings and scanned the area.  Who's bright idea was it to build gazebos and pavilions?  Why on earth plant so many bushes and trees?  Don't they know that people might want to try to find an errant quadcopter here some day?  So, I stood stock still, took a deep breath, listened very closely and goosed the throttle.  Off to the left I hear an faint whine.  Whew.  Okay, so he's not on top of a building or snuggled down in a mockingjay nest.  I kept goosing the thottle lightly and listening, following the whines.  At last I found him behind a little gazebo upside down and blinking madly. I quickly recovered him, stopped the recording and started the trek back to the field.

Lesson learned:  Stay within my abilities and learn to walk before trying to run.

I am VERY lucky on several counts:

1. I didn't loose or break Little Red on his second flight.
2. I didn't damage anything/anyone when he soared out of control
3. I learned how easily it is to get disoriented when a little square quadcopter turns into a black speck at altitude.
4. I got some amazing pictures from this flight.

And First Repairs

I'm an old model builder from many MANY years ago, so repairs, for me, are a natural part of flying models.  In fact, it's pretty much "THE" part of flying models.  But more on that another time.  Today the repairs were to replace the body (see previous post "First flight, first crash") and one motor.

I did try gluing up, just to see if it would work, but the only CA I have in the workshop right now dries about as fast as furniture polish.  I didn't expect much from the glue-job, as the body of an X4 is full of compound curves and projecting pods.  I didn't really have a way to keep it straight during glue-up, so I wasn't too upset when the glue didn't bond well.

So, after the maiden flight I had to order a new body for Little Red.  Hobbex in Malmö doesn't carry the bodies in their stock, and they could order it to the boutique, but it was at least as fast for me to order it direct home.  Which I did.  In fact, knowing me, I ordered two.  And while I was at it, I grabbed a set of motors. Today the body shell arrived and I set to work replacing it.  It wasn't a difficult task, but it was tedious.  The motors need to be disconnected from the flight controller board to get them out of the old body (I needed to replace on of them anyway) and they construction of the X4 has the motors soldered directly to the flight controller.  The smallest soldering iron tip I have felt about the size of a baseball bat in there on those tiny solder points on the flight controller, but with a little patience (yeah, right) the motors came loose, everything moved to the new body and everything went back together again (Note: Keep track of orientation so that the right motors go back in at the right places).

A comment on the screws on the chassis:

They are tiny.  I mean tiny.  Microscopic is getting close to the right description.  So if you take apart an X4, get the absolutely smallest philips you can get and see if it will work (my smallest phillips in my jewelers set was too big, so I used my fallest flathead screwdriver).  Another tip is to have a plastic tray of some sort to work on, preferably with a raised lip around the edge so rolling screws don't take a nosedive onto a sawdust-covered workshop floor.  Ohh, and even more importantly: don't flail around wildly with your elbows in search of your coffee cup and knock the carefully placed high-lipped plastic tray holding microscopic M1x3 screws onto said sawdust covered workfloor.  Not that that happened to me ... more than the one time.  Fortunately the four screws holding in the battery compartment are of the same size as the outside screws holding the body together and I decided that four screws was probably more than necessary to hold things in place, and two of those screws went to the outside.  Those missing screws are bound to show up sooner or later.

But long story short: The body and motor replacement went well and tonight after the kids are down Little Red will take to the skies again.

First Quad ... first crash

I woke up this morning from dreams of flying.  I've been thinking a lot about quads and FPV and last night I dreamed about it.  Fortunately, I have the most understanding wife in the world and she said "Sounds like you should go get one."  Well, if you're going to twist my arm behind my back, fine then!

So I called around to Teknikmagasinet and CoolStuff and the finally Hobbex before I found what I was looking for, which was a Hubsan X4 with camera (later to be identified as the H107C).  I've chosen this as the entry-level for me as it is, frankly, the lowest price with an on-board camera.  Turns out that the H107C is out of stock pretty much everywhere in the local area except for Hobbex at Burlöv Centrum (Malmö).  As luck would have it, they happened to have the most attractive model (red with silver stripes) in stock, and that's what I bought, along with an extra battery (which I sheepishly confess plugging into the USB phone charger in the car on the way home).  Eager?  Me?  Let's just say that I had the whole thing unpacked and the manaul read while waiting in the car at the grocery store while the wife ran in to get a few things.

Speaking of unpacking, I found the advertised red quad, controller, extra propeller blades tool, charger and battery all where they should be.  The manual I found under the plastic tray.  Where's the propeller guard?  I guess I'll have to go back to Hobbex or Teknikmagasinet and get one.

So after painfully waiting through dinner, evening rituals and getting the kids in bed, I got to take the little red X4 (dubbed Little Red, as opposed to Secretariat, aka Big Red) out for its maiden flight.  Being the natural born genious, I took it out behind the building to the nice, small, enclosed, half-asphalted yard.   Two words: Bad Idea.  Asphalt and plastic flying models coupled with newbie pilot makes for disaster.  I kept things under control for the first battery.  Everything went well.  The X4 is stable, but I found it to be quite sensitive, even in "normal" mode.  I was quite heavy-handed on the controls and poor Little Red did its best to keep up.

So, in with the second battery!

Now I'm an experienced pilot.  Time to see what this little guy can do!

... would be a good candidate for "famous last words" for a novice RC pilot.

I took Little Red up to the second-floor level of the building where I thought I'd do a little peek-in on our kitchen window.  Things got turned around pretty quick, and left became right, back became front, and up became up became up became up.  So Little Red sailed out over the back gate, hovered bravely over the street and drifted steadily away until the voice of Panic took hold of me and cut the throttle.  Lesson #1: Dropping a Hubsan X4 from 15 meters onto asphalt WILL break an arm and a motor.
At the very least.  Good feelin' gone.