Carsten Svendsen

What do you mean by that I will stall? How can I get no where when I'm everywhere (in the air) ?? It was the meaning that I'd go all-in as much as possible with LEGO parts, but I guess you're right that it's pretty important to control the plane the way it is. How much torque do you think is needed to control the flaps while airborne? I found this one and I don't know if it's got enough torque. Nevertheless, how am I going to fit an axle on such a thing? And does it work like intended just because it says "servo" in the name? Size: 22x11.5x27mm Speed: (4.8V @ no load): 0.12sec/60 degrees Turningforce: (4.8V): 17.5oz/in (1.2 kg/cm) Temperature : -30 to +60 grader Voltage: 3.0-7.2 Volts weight: 9 g I was just going to fit in some LiPo batteries and a some non-LEGO transmitter/receivers to control it. Added: This controller looks good and has a lot of functions: http://hobbyfly.com/kaempe-januar-udsalg-511/spektrum-dx6i-dsm2-m-ar6210-modtager-6201.html If purchasing that controller + receiver, I can also purchase 4x of the servo's a bit cheaper it seems. But is it the right thing? To do?

I'm glad it can be solved that easily. It's only half a stud higher than the wing it self - still 25% though, but on a very small area on all of the wing surface Nice drawing :D There is no question about whether or not i should use micro motors for the ailerons since it'll reduce play by a great amount. The torque has been increased 8 times though, remember that. I haven't thought of adding servos in the tail. I would need a total of 3 servos which would add a lot of weight, especially when it's that far back on the plane. I have measured and it seems I can be able to fit all 3, but I only have 1 atm and am using that for the steering wheel, so I'll have to order some on BL to test with. They're expensive but not as much as the micro motors. Well, that's just for turning. The important aspect of the whole flying thing is the up/down movements, and that's where I think you're right about the servo motors. Turning and banking isn't as important as I can't crash in mid-air :) This is what I have spent the last few days on. Getting a micro motor in there. Although, it does turn very slowly and there's some play in it. I haven't tried with the newer 8t gears since I don't have any. I could order some on BL along with the servos Here's an example of the above

OP, can test these new gears with the worm gear to see if the play has been reduced in comparison to the old gears.

No, I know they won't. See the vid I posted further back in this thread for proof

Notice that I plan on using only the studded micro motor plates in this case Note: Picture no.2 is the newest picture (reinforced the micro motor's position

Today I've rebuild the wings in order to reduce the amount of play in the flaps. I had to retract the carbon rod a bit in order to fit it. I hope that the amount that's too tall compared to the rest of the wing doesn't have influence on it's flying abilities. Should I place the micro motor beneath the wing instead? EDIT: Forgot to mention that this first picture is just to show that carbon rod under the wing. Besides that, there are 5 additional mounting points on the wing. I'm about to reinforce the body where the wings are so that the plane won't get completely oval when airborne (and to reduce a spring-like effect in the body). I have also removed the chains driving the tail and hope to get some great idea on how to make that the best it can be. Notice in this last picture that it sticks half a stud above the wing. Would it be better to have that kind of obstacle on the underside of the wing? Forgot to mention that I weighed the plane with a luggage hand-weight and it old me that it was only 4,15 kg. AWESOME

I searched that dinosaur toy on youtube and I don't think that the motion is what I'm looking for. I found this however, I wonder if I could somehow make it work both up- and sideways: http://yiharuablog.wordpress.com/2013/01/02/the-year-of-the-snake/

Ah, center of gravity, yeah that's quite important, I just didn't udnerstand what you meant by CG. This should easily be solved by placing battery packs correctly.

I have no idea but if so, the weight shall not exceed 10,7 kgs - cuberoot((19.150/15,65)) I think it's possible, but lets see

The weight will always be a problem concerning airplanes. I believe that it weighs approx. 6-8 kg as of now - I need to purchase a luggage weight in order to be certain. Since the airplane is almost done and minor details are in need of a fix I don't think it'll much heavier than it already is. Of course the batteries motors and propellers will add the weight a little, and that's inevitable. BTW, I'm no pilot and I know nothing about part names, but I hope you get the idea. a) This has been the big hassle for me and I pretty much spent more than half of the total time on the airplane, making the wings, rudder and what not. I won't be able to achieve complete aerodynamics (obviously) but I can get pretty darn close! b) This is a big factor for sure. As of now, there's way too much play in all control surfaces. I still need to rebuild the tail flaps, so in order to eliminate play as much as possible while making sure there's enough room for the mechanics I've decided that I'll put in 5 micro motors in a 1:8 ratio (worm + 8 tooth); 1 in each wing, 1 in the rudder and 1 in each tail flaps. The motors are small and will "easily" fit anywhere close to the moving flaps/rudder. However, the micro motors cost literally and arm and a leg on bricklink so if anyone has got some lying around they don't want anymore (LOL), I'll gladly take hold of them for a smaller price. c) The structure it self is plenty rigid both up- and sideways. However, the tail is really flexy in a rotational matter. This isn't so good and I don't know what I can do to stabilize that. I hope that once it gets coated with something, it won't flex as much. d) ?????? e) 29 kg sounds like a whole lot, heck even 14 kg, I don't think it'll be that heavy but we'll see. I think I'll need to have some special crafted propellers just for me that has got the right size and shape. It'll probably be quite expensive too

That looks so lifelike! Congrats on building that

It's got a thermal limiter - skip to 0:55

I just saw the video you posted and assumed you must have seen some gain values (Kp, Ti, Td) in the programs. Which programming language are you using? I have downloaded the NXT-G program block and it doesn't offer many solutions/possibilities. RobotC on the other hand offers loads of possibilities and this is where you choose your gain values. Download the demo and lib files from here and you will notic it straight away. You're an electrician just like me, so I assume you know everything regarding PID-controllers A video of how you robot performs now would be perfect because right now, it's almost impossible to say which settings are in need of a change.

What are your gain values?

I have tried 19,2 volts (two 9,6V lithium ion packs), and I can say that the motors smell really bad afterwards - they still work, but I wouldn't recommend it as the carbon/brushes inside of them will degrade not only faster, but super fast! If you take the 9396 rotors and build a mechanism like the one below (smaller of course) then perhaps you can get it up if it's not too heavy. The special part in the middle is made of 3: http://www.bricklink.com/catalogItem.asp?P=2906 http://www.bricklink.com/catalogItem.asp?P=2907 http://www.bricklink.com/catalogItem.asp?P=2908 From youtube: Lego Part Number 2906 is the rotating swahplate, 2907 is the uniball, and 2908 is the stationary swashplate. Part 2907 is a splined ball that is locked within 2906. 2906 is supported by and locked to 2908 but can rotate freely along a horizontal axis. Because of the spines on 2907, the entire assy would not slide vertically along the main rotor shaft. I used a drill bit to remove the splines allowing the ball slide freely.

I tried every method of building a chopper and it won't work - It'll be too heavy or the cable will drag it around like a balloon I have 12 of those white propellers and a couple of those buggy motors. unfortunately I haven't got that small tail rotor, but I can tell you from my experience, that you need A LOT more torque from that small tail rotor to be able to counter the buggies'. Maybe if you have a 9 volt main rotor, and an 18 volt tail rotor? However, that would probably only last 20 seconds. You have to be careful not to get too many ideas. This is EXACTLY how I started building my airplane - it costs money - lots of money. I won't be able to make it true LEGO though since those propellers will just bend when too much torque is applied. - You have been warned!

See my wing: http://www.brickshel...y.cgi?i=5501140 Simple construction, only 2 studs thick and low-weight. By using this method you can have any angle on the wing you desire. I know it's not as awesome as OP's airplane wings, but that's not my objective.

That model looks awesome and very detailed. Congrats on the fine work :)

aaah that makes much more sense. However, doesn't it require a lot of force to prevent them from falling out of the ?

Looks like it'll work great. I still don't understand how it controls the gearbox. Do you have a pin+joiner or something to work like a clutch gear?

From what I can tell, M1 drives the switchring on M2 right? If so, I can't see the purpose of either the steering wheel or actuator, as the vehicle would stop moving if turning left (for instance) and move if turning right. Also, the actuator wouldn't move at all because of the switchring function. Am I completely mistaken here?

Seems a bit funky. What kind of a toy is that? If you've got it personally, couldn't you try to build a model of it in LEGO, because I can't tell how it's made from those pictures. @F0nix - When's that upload coming?

A search turned up no results. Would it be too much to ask for you to post a link?

I realize that this would be a tough problem to solve. I'm not a coder or anything, but isn't it possible with multiple rotation links, that the main link (in this case the gear) creates a variable for the second link which creates a variable for he third link and so on? Again, I don't think this feature would be worth the hassle because I've never seen this kind of movement made before in any functional model. Perhaps it could prove useful in a GBC module, but that's about it. If you find it too hard a nut to crack, then forget it unless you want a challenge I have supplied a model with only 3 links, and even this won't rotate. The file is made in version 7.13.17, and the model I created at home was in the newest version. Basically, you just add another separate gear, liftarm and a bent liftarm for each other part of the sequence. Sample.zip

I don't think gravity is the case here, more likely play in the gears as you say. Now that I think about it though, a dolphins tail does go more downwards than upwards. I just tried that, and you're right, it does look more lifelike. However the tail won't be straight in the middle, but that could probably be solved by the weight of the tail whenever it's done.