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About mieczotronix

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  • Birthday 07/29/1971

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    Warsaw, Poland
  1. For your purposes (orientation metering) you may assume the compass is just a ball with eccentrically positioned weight enclosed in a transparent sphere immersed in some fluid. The weight is inside the compass ball, at its bottom. That's why the ball keeps orientating iselfs. Disregarding magnetic properties of the compass, which are irrelevant here (unless you'd like to orientate your plane relative to magnetic North), what'you re about to do is to take a pendulum (which is the eccetricaly weighed ball) and measure its movements. So you're basically trying to develop a crude accelerometer. It won't work in a plane taking a turn due to other forces acting on it as Terry told you.
  2. I use FMA Co-pilot and it seems to work pretty well. It's not dependent on light as it senses the IR radiation of earth vs. sky. The manufacturer claims it will work at night as well. However it may have some difficulties when flying over snow, water or in between mountains (it needs flat horizon). I guess it's the best one can achieve. However, you won't eliminate wing swaying completely with neither of these systems (IR, visible light, gyro, etc.) as all of them work to the same principle - i.e. first the plane has to move a little so a sensor can detect the movement and force plane controls to compensate for it. How much the movement will be noticeable will depend on the stiffness of plane controls, airframe, and servo speed, etc. I used to fly a 1,6 m foamy plane (quite flexible) with FMA Co-pilot with a camera onboard, and on turbulent days movies turned out to be unwatchable, even with the FMA Co-pilot on. Of course it did help a lot with controlling the plane, so I ended up using it for flying high where I kept easily loosing orientation just to keep the plane level rather than to completely stabilize it.
  3. Ok, I bought the gear I asked 'bout in the previous post. Here's how it looks on the fuse kind of funny looking, but I hope it will perform well on tall grass the landing gear and wheels are very light, it's not noticeably heavier than stock lg with 2 3/4 " wheels. I've also bought a clever tailgear with built in servo saver (those springs) I'll cut away some balsa from the fuse, put 8mm plywood instead and fix the tailgear to that.
  4. Ok. Thanks for your suggestions. I am now preparing to buy some gear. Tell me what do you think about this 1) Kavan (German) 125 mm inflatable tyres (that's almost 5") 2) Carbon landing gear: width 390 mm (15") / height 185 mm (7") 3) HS 225BB for ailerons (fast) 4) HS322HD for flaps (can be slow -> low current draw) 5) HS82MG for rudder & elev (fast, powerful and heavy-duty) 6) 38mm (1.5") tail wheel with some kind of alu brace for attaching it to the fuselage 7) 6mm (4 1/4") carbon rod + 7/6.22 mm brass pipe - for bayonet mount for wing + 8mm plywood for wing mount 8) 5000 mAh 25 C 4s1p LiPo - 46 x 50 x 144 mm and 660g (23 oz) weight - will I be able to easily balance the plane assuming the battery will go in between bulkhead #1 and #2? The space between bulkheads #2 and #3 will be the cargo bay, where I will put my ixus or another payload. I installed a floor inside it, to which I will suspend the camera on velcro. Above the floor I have room for electronics and BEC batteries (I can even fit 2200 mah 3s lipos there). Another option I've been considering battery-wise is to buy 2x 2200 mAh 3s1p (rather than 4s), which I could use in my heli. What do you think about that?
  5. Thanks. That's the one I've been building, except its kit rather than ARF. So from what you've been saying it is tail heavy, right? So maybe I should thin it out a little by building framework rudder and tail rather than solid one? Should I really try to lighten it up at rear or that is not as much important and I will balance it somehow. How much bigger? Since I have to order a pair anyway, maybe I go straight for the biggies? I think I did read all posts about Telemaster Electro here and on rcgroups. But it seems like everyone got ARF version. Thanks for other pointers, very valuable.
  6. Hi. Having read all the good stuff about weight-carrying capacity of Telemaster I decided to build one myself. I ordered a kit from HL USA. This involved some hassle, as I had to use a third party shipping company to carry the oversized box by sea to me. After two months of expectations the kit arrived and I've started building my Electro Telemaster (HL kit - 180 cm wingspan) from scratch. I wanted to build a kit so I could easily adapt it to carry my payload. At the moment it is an Ixus, a small cam on pandora pan&tilt + some more stuff like eagletree data recorder, hexpert zlog ,some of my electronics and possibly many more in future. I plan to build the plane with the following features: - flaps - AXI 2826/12 (I already have it). - split wings (I don't know yet what to make the bayonet mount of - I got a spare, bent 450heli boom made of some aircraft grade alu - very stiff 13 mm inner diameter - don't know if it is gonna be of any use for it) - put tail & rudder servos somewhere in the tail section (possibly inside the fuselage under a hatch) to free space near COG - lots of hatches and compartments to hide stuff like electronics, batteries, connectors, switches, indicator LEDs ... - compartments in left and right wingtips for vid tx and gps I've been just finishing the fuselage framework and since I want to build in it those various facilities, I need some input from you. Here are my questions: 1. Where exactly you put your lipos in yuor ETMs (what kind of 3300/4000 mAh 3s/4s)? i.e. how far from the firewall (1st bulkhead). I haven't ordered lipos yet. I have some 2200 mAh 3s packs. And I was planning to buy two more and use them in parallel in ETM and separately in my other smaller models. 2. I've been planning to use a small li-po pack instead of BEC. Should I use one for servos + video stuff or 2 separate. What do you suggest? 3. What size of wheels would be right for very rough terrain (tall grass) - will 100 mm foam wheel be any good? 4. Would you recoomend HS-81 / 82 (mg) or standard cheapos hs-322 servos? 5. Should I go for detachable rudder or stabilizer ? 6. I plan to install a mount for pan serwo in the bottom of the fuselage in front of wheels and possibly under a wing (how far from the fuselage you have your underwing cams) I guess that's it for now. Expect more questions as I progress with the build. Of course feel free to post your other suggestions of what I could improve, build-in in the model. regards Chris
  7. I already purchased a kx-131 clone and put it on pandora, but I miss resolution of this cam that's why I've been still thinking about it. I've had also an opportunity to see this cam's waveforms hoping they will point me to some kind of solution. Supply-wise I run the cam of 3s lipo. It is rated 12V and it manages to work with unchanged signal parameters until something in the range of 9.6V then it just shuts off. So I guess power supply is not the issue here. The cam has CXD3141R sensor onboard, I've see someone posting CXD3142R datasheet in another post. The cam has its chip's serial lines output on 4 pads on the PCB so it can be easily reprogrammed to aonther gamma / dynamic range if anyone knows how to do it (as it seems it is now tuned to cctcv purposes - to render well human faces). So I put it back in the box or install it back in the dome and on the wall of my home until better times come. Anyway thank you for your valuable insights.
  8. Well, your probably right about that. But I just made one more test before I give up on it. Here it is: When I added a 10k pot across gnd and vid out, even the slightest movement of the pot makes the signal fed to my monitor drop to 0.3V And here is the difference it makes: before (bare camera) and after obviously the 0.3V signal is not that transmitter or osd likes, but this somehow leads me to believe that AGC is not the real cause here. If the washout would be due to AGC, when I reduce the voltage the clipping should still be on the picture, yet in this case you can see that details in the previously washed out area start to appear (quite a lot of detail). The camera hasn't moved and lighting conditions hasn't change either. Well... what do you thing I also pointed the cam directly at my halogen desk lamp. I actually put it to the glass in front of the bulb. The lcd screen was completelly white, yet the clever cam managed to see some details. Anyway those flat areas on the graph below indicate the maximum level achievable. So it seems it is indeed -0.5 + 0.5 V range.
  9. ok, thanks, I still wonder if this is AGC because the same thing happens in broad daylight, everything igets overexposed. While observiing the waveform on scope I also discovered that when I move the cam towards/away bright light source, the whole waveform shifts up and down by some 0.1-0.2 V. A I think the waveform is clipped at the same height when the cam points to a bright source, the clipping is already visible on the right side of the first picture, I manipulated the cam to get as much clipping as possible. I'll try this evening to connect a 100k pot across gnd and cam_Vid-out to see if it helps to darken the image as I remember it did help a little. What should I do not to mess up the impedance completely?
  10. Can anyone clever enough please tell me what's wrong with this camera. First of all in this setup I mean in dark room with camera lens pointed to a black box... ... I get this whashed out image on my video recorder... although this is not a real-life situation, it's quite representative for problems i've been having with this camera. ...while the camera is producing this on the scope... this is line no. 4 of the white image above I mean, when I connected it to the scope I was hoping to see the waveform shifted upwards (as it's supposed to range from 0 to sth. about 1V, right? But as you can see its almost symmetrical -0.5 / +0.5V. The camera is SONY 1/3 Super HAD taken out from a cctv dome. What kind of circuit I need to add to the video output from the cam to get at least the right voltages (I am begginning to be afraid that I will never get a decent saturated picture from this cam). EDIT: Now I checked the picture from my DV cam. It shows up good on the same video recorder the previous cam did not. The strange thing is, it also produces a waveform in the same volt range (-0.5 to +0.5V), although somewhat weaker. (the picture was nearly the same - as whit as I could quickly get - switched on nightshot and pointed lenses at the lamp) Can not make anything out of it.... BTW: 75 ohm resistor added between video and gnd changes nothing
  11. I have a 1/3" color cam with SONY CXD1341R chip. Its somewhat larger type of pcb camera consisting of 2 42x42mm boards. What's interresting is that it has 4 holes where I could solder in a connector, and according to your CXD1343R datasheet there are SCK / SO / SI/ and XCS signals available on these pads. Do you think I can connect SCK to SCL and SI to SDA of a microcontroller (and select the CXD chip with XCS) and try to reprogram the camera? using I2C ? I've been having some problem with this camera, which although giving a detailed picture has been delivering too bright (washed out) video. I was alway wondering whether I could tweak it somehow and mayby this would be an option...
  12. I dont' have BWAV gear but some other camera, which suffered from switching p/s noise. I actually solved it with low drop lin reg but just would like to know the resistor trick so I have more options when I encounter similar thing again. Do you mean this is an inductor you connect in series on Vcc line? What is the inductor's rating?
  13. docphi, what kind of resistor is that (value, where to connect)? I've just looked over blackwidowav website and found nothing. Could you please provide some details?
  14. I've been just trying to work out a solution for the same problem (codable with fixed precision maths in Atmega) Could you provide a glimpse on how to do it (don't need a worldwide solution)?
  15. just my two cents - try increasing camera resolution (maybe kx-151 instead of 131), your brain will obviously get more data to process and to develop 3d vision - I don't think you'll have problems with aligning two cameras mounted on separate servos, from what I've experienced with my vision system and my brain after an accident some time ago, which messed up alignment of my eyes I can tell you human brain is pretty well adaptive and will easily compensate for slight misalignment of two images. Maybe it will require some training (like seing those stereograms that were the hit in late 90's) but nothing exceptional. So with cameras spaced 1 m away dont expect to get problems with double/vision and cross-eyes. The only problem likely to occur would be if you''ll be flying close to some obstacles as someone else has pointed out above.