Shop OBEX P1 Docs P2 Docs Learn Events
Ken/Cluso99/ W9GFO/JasonD's QuadCopter Build Log (updated info ELEV-8 + availability) - Page 35 — Parallax Forums

Ken/Cluso99/ W9GFO/JasonD's QuadCopter Build Log (updated info ELEV-8 + availability)

1323335373843

Comments

  • dmagnusdmagnus Posts: 271
    edited 2012-03-26 07:32
    Ok I'm going to take all of the above in one post (and ask a couple of more questions, too).
    BR: I hit a deck post at an altitude of about 5 feet above where it eventually landed - on it's props. The two broken props are on the motors that seem to turn just fine. The two motors that don't turn very well are the ones with good props. So, I think it hit the deck post with the side where the props broke, then fell down and was trying to turn the props for a few seconds until I got everything turned off.
    I killed the throttle immediately when it started to go out of control - well before it hit the deck - but the motors were still turning at pretty good rpm because the altitude hold was trying to keep it flying. I didn't hit the switch fast enough to shut the altitude hold off.
    In retrospect, it's probably a good thing it hit something close to the ground. Otherwise, it might have taken off to high altitude and flown away.
    JET-w: Yes, I'm totally confused about these "gains" too. I have a DX8 with AR8000 and am having similar issues. My travel ranges go from 0 to 100 on all channels - no negative possible. This is what got me in trouble with the altitude hold...
    Tiger: How do you get the motors apart? Take out the two small set screws (did that). Do you have to take off the tiny circlip that holds the shaft in? I've got to get a tool for that. Is there a diagram someplace for them? The motors DO turn, but seem to be "sticking". I bet you are right, the magnets are loose and impeding the rotation...
    Also, I'm not going to use the Prop BOE as a server tester, just to run an ESC to test these motors when/if I get them fixed without having to mount them on the ELEV-8.
    Cats92/JET-W: My ELEV-8 flipped over when I first started to try to fly it. I took it into the shop and carefully checked the connections from the ESC's to the HF Pro and from the receiver to the HF Pro. I had two ESC's in the wrong place and then found out that I had two props on the wrong motors. After that it flew fine until I started to try to mess with the "sophisticated" stuff.
  • ratronicratronic Posts: 1,451
    edited 2012-03-26 11:41
    dmagnus in case you didn't know brushless motors need a load on them such as a propeller when operating at not to much faster or longer than the test code I posted.
  • JET-WJET-W Posts: 6
    edited 2012-03-26 13:32
    Cats92 wrote: »
    Hello JET-W,

    I am also a beginner and when my quad flips instead of taking off it is often that :


    * the motors at not runing in the right direction: 2 motors CW and 2 motors CCW (read carefully the Hoverfly doc)


    * the propellers are not in the right place : 2 propellers normal (running CCW) and 2 propellers pusher (running CW)


    * the Hoverfly card is not in the right orientation (look at the configuration ( X or + ) in the Hoverfly doc.

    You have also to program (better with a Turnigy card : costs about 7 $) and calibrate the ESC (one by one connecting it to the throttle channel of the receiver)

    Cats92
    1. I am running the X configuration, like the Manual the the motor CCW,CW,CCW,CW. Starting from the left front going clockwise.
    2. The propeller I am not sure what the normal or pusher is. But at first I had it on the wrong motor. I raised the throttle and it still stays on the ground. When I went
    back and check the pictures of all the Elev-8 on this forum. I adjusted the Propeller to its proper motor. Then I raised the throttle and 2 of the landing lift while 2 is
    still on the ground and the Elev-8 Flips over.
    3. I brought the Turnigy Card along with the Kit. I programmed the ESC before the installation. The only difference that I have I believe is that The Hoverfly
    Manual states that the Battery Type should be Nimh and I have it on Li-ON. I programed the ESC before I build the device because the manual calls for removing
    the power on 3. of the ESC on page 37.

    Unfortunately one of my propeller broke after the numerouse flips. I have to wait for the Crash Pack to arrive before I can continue further.

    Do you think If I attached the Elve 8 to something like a (ex. fishing rod) hanging of the ground and learn to fly that way. So that even if it falls it would not land on the ground and damage any part. Workable ?
  • dmagnusdmagnus Posts: 271
    edited 2012-03-26 15:28
    Yes, I'm going to make a small "propeller" out of one of the broken ones. Should give it enough of a load, but I'm not going to run them very much...
  • JasonDorieJasonDorie Posts: 1,930
    edited 2012-03-26 16:54
    Jet-W:

    The easy way to make sure that the propellers are the right type is that they should be blowing air down, not up, when attached to the motors. (that's kind of obvious I guess, but that's the easy way to tell). A normal prop pulls air past the motor when turning clockwise. A pusher propeller is made to spin the opposite direction, for cases when the motor is mounted on the back of the plane, so they expect to turn counter-clockwise.

    Before I flew mine, I grabbed it from the top by the plastic plate, held it out at arms length, and slowly spun the propellers up a little at a time. Do it slowly, and hold it tight. It may move in a direction you don't expect, so be careful. If you do this, make sure it's away from you, and you won't hit your arm or any loose clothes with the propellers.

    If it's working the way it's supposed to be, it should only want to go UP, and should not try to twist or tilt in any direction as you add throttle. If it does try to tilt, you probably have the propellers set wrong - All the air should be blowing down. If the air is blowing up, you have a propeller on the wrong motor.

    While the propellers are spinning, and all the air is blowing down, if you try to tilt it to one side, it should resist you. If it does not, your gains are set too low. Once you have the gains set to where you can feel it resisting a tilt from you holding it, the settings should be good enough to try flying it.
  • BRBR Posts: 92
    edited 2012-03-26 18:13
    JET-W...I have a spectrum dx6i with ar6215 receiver. To Jason's point I think spectrum uses the +/-100% range definition, so 50% on the gear (I.e. gain) corresponds to a 1.75 ms servo pulse width...assuming my memory is correct here. One thing that really helped me sort out the servo ranges and control setup was to use a propeller board as a receiver diagnostic tool. I have a PPDB and it is easy to use the "receiver" object from Jason's quad-x code along with a debug object to output the receiver signals to a debug terminal. The reciever can be powered with 5v from the prop board and a 5k resistor between each reciever pin and prop pin does the trick. Makes it really easy to see what ranges your receiver is putting out in response to control stick inputs and gear switch settings. So from memory, if you hook up your receiver to a prop board and look at the signals being put out on each channel, you should see:
    Throttle: Min=1010us pulse. Max=1990us pulse (throw the control stick from one extreme to the other to see the range)
    Aileron, rudder, elevator: same as above
    Gear: 1750us

    I don't know if this makes sense or not, maybe I'm just confusing things. Anyway, if you're not sure your receiver settings are doing what their supposed to, that's a pretty fool-proof way to check.

    Also, When I programmed my ESCs, I used the NiMH setting per instructions, rather than the LiPO setting one would intuitively expect. I think that's unlikely to be a problem if your batteries are charged, but if I understand correctly, the ESCs are "smart" enough to know when a LiPO battery is discharged and will cut out...presumably not all 4 ESCs on the quad would hit the cutoff at exactly the same time...potentially with a crash ensuing. Maybe someone that knows more about it can check my facts, as I'm not 100% on this.

    Dmagnus: I have had a couple crashes where the props stick into soft earth and are stalled for a second or so, seemingly with no ill effects. Maybe I'm just lucky...if so my turn is coming. But in my limited experience, the motors seem reasonably robust to momentary stall.

    You mention altitude hold....I haven't gotten around to trying that yet but hope to eventually. I've already got a maxbotix sensor. Just not the time to mess with it...have you had much luck with the alt hold when you had it flying?
  • Eggplant!Eggplant! Posts: 17
    edited 2012-03-26 20:17
    Hello everyone!

    Second round of test flights this evening. Much better! Not a single crash, and I had nice smooth landings! There was even one point where an unexpected gust of wind blew the quad on its side and I managed to recover. I'm so happy!

    I found my wobble was probably due to a loose screw on one of the booms. One of the ones with the lock nut wasn't turned down tight and there was a little play in the motor mount. I fixed that and set my gain down to 50% (Spektrum DX6i, AR6210 receiver). A MUCH smoother experience. I think I could possibly go a little lower.

    I did record some on-board footage, but the sun was low and you can barely see anything.

    I played with the altitude hold setting a little bit to see what it would do without a sensor. (also at 50% gain) Pretty much nothing I could notice besides turning the LED blue.
  • Chris SavageChris Savage Parallax Engineering Posts: 14,406
    edited 2012-03-26 22:46
  • Cats92Cats92 Posts: 149
    edited 2012-03-27 02:02
    Jet-W,

    To know if the propellers are running in the right direction i put the quad on the ground and a sheet of paper (or light cardboard) under one of the propellers at a time : when you spin up the motors carefully you can see that the paper is pushed to the ground , if the sheet is going up then you propeller is NOT OK . I make this for the 4 propellers , stopping the motors to put the sheet of paper under the next motor.

    If you have APC Propellers (which are very good) note that on the pusher you read 10 * 4.7 P and on normal ones you read 10 * 4.7
    I have always at least 4 normal and 4 pusher in stock (you can buy on the Aeroquad net site )


    For the battery it is safer to choose Nimh type (with lipo type , when the battery voltage goes down one of the motors may stop during a flight.
  • dmagnusdmagnus Posts: 271
    edited 2012-03-27 05:05
    BR: Yes, when my crash occurred, it landed on it's back with the props still turning. Two of the props broke when it hit the deck post and the other two were sitting there "twitching" (stalled) until I got to it. I think, because the switch was set to altitude hold, it kept the throttle up even when I backed it off completely on the transmitter. I didn't think to switch off the alt hold until I had already shut down the quad. This was the first time I had tried the altitude hold (Pro board). I'm going to go a lot slower next time. I'm also going to get my gains set properly before I try to fly again. I also have a gain setting for the GPS, which I haven't tried yet, either. I also don't see any negative settings for any of my gains. They will go well beyond 100, but stop at zero on the low end. That is one of the things causing the confusion. I think the DX8 and DX6 must be slightly different.
  • TigerTiger Posts: 105
    edited 2012-03-27 23:13
    - removed -
  • Roy ElthamRoy Eltham Posts: 2,996
    edited 2012-03-28 00:54
    Might want to beep out the language at the very end of that....
  • TigerTiger Posts: 105
    edited 2012-03-28 21:39
    Roy - Sorry about that! Didn't notice it until you mentioned it and I turned the volume way up. There is no way to edit someone elses YouTube post so I just took it down.

    ...Tiger
  • JET-WJET-W Posts: 6
    edited 2012-03-29 09:44
    Cats ,Jason and BR, Thank you guys for your help. I just got my crash pack today and I reinstalled the propellers. With Jason’s explanation I was better able to put the propellers in the right place and have a better understanding of the build process. I Then put a piece of paper like Cats mentioned and I saw air pushing down on the paper as the motor turns. Afterward I recheck the ESC programming and reset the “Battery Type” to “NIMH” from “LIPO” like BR mentioned. In the process I found out that my connection from the ESC to the Hoverfly sports-- 2 esc were plug on wrong pins. I then set the Gear at 40%. When I was ready to fly, I push the throttle about half way, The Elev-8 jump up like 12 inches from the ground then landed back down. I knew then that it’s not flipping over and that going forward its learning to fly and having fun. Thanks again everyone.

    Oh one more question, If you guys can help me out, Cats mention about getting a Turnigy card for programming. On row 5 where it states “Start Up Mode”, On the Hoverfly Manual, it states to set it at “Hard or Fast”. However, on the card, the only options are “Normal”, “Soft” and “Very soft”. Which one do I pick? Thanks.

  • Nick ErnstNick Ernst Posts: 138
    edited 2012-03-29 09:46
    Here is the Hoverfly Diagram about how the propellers should be mounted and rotating. If you have the propellers mounted as shown, and they are rotating the wrong direction, simply change the ESC/Motor connections around and re-check your motors. If you are still experinecing issues with flight once these have been checked and confirmed, then it is a gain issue with one of the channels on your transmitter.

  • ratronicratronic Posts: 1,451
    edited 2012-03-29 12:07
    JET-W it should be set to "normal". In the HoverFly manuel it states "never soft" for startup mode and that's how mine are set.

    Edit: Here is a list of the mode #'s and how I have them set.

    mode, set to
    1, 2
    2, 2
    3 ,1
    4, 2 - but I use a battery alarm
    5, 1
    6, 2
  • Eggplant!Eggplant! Posts: 17
    edited 2012-03-29 16:29
    More flying today. More tweaks. Getting better at this! My gain is around 35 now and seems comfortable. Probably the hardest part is finding that sweet spot in the throttle that makes it hover. I'm usually drifting up and down and just constantly adjusting. I ordered an ultrasonic sensor the other day, so it will be neat to try out altitude hold.

    I got a little more brave today and was punching the throttle harder. One thing I noticed is when I do that, one of the motors (not sure which one) tended to sputter or maybe rev up and down quickly, causing the copter to pitch forward. If I raise the throttle more slowly it doesn't do this. Any idea what could cause that and how to correct it?
  • Ken GraceyKen Gracey Posts: 7,386
    edited 2012-03-29 16:50
    Eggplant! wrote: »
    Any idea what could cause that and how to correct it?

    Yes - check the following:

    - Prop adapter to see that the shaft is not bent, causing an oscillation at higher RPM
    - Propeller for missing pieces as a result of a prior impact
    - Is the motor firmly attached to the base - can you pull the case up from the base?

    Holding it down on the ground, rev it up. Can you "see" a problem from that specific motor?

    If there's still a problem, I'd think the gain is probably too high.

    Ken Gracey
  • TigerTiger Posts: 105
    edited 2012-03-30 01:26
    So tonight I'm injection molding until the wee hours. That consists mainly of pouring ABS into the machine once an hour, checking some readings, and trying to stay awake the rest of the time in case something blows up. This gives me time to do something I've been wanting to do for quite a while. I don't think there has been anything on this forum that has caused more grief and confusion than prop orientation. This seems to come up over and over and over. I to was confused by the documentation on my first build. I wasn't sure if the motor direction (CW/CCW) was as viewed from the bottom of the motor, the top of the quad, or what. I think everyone will agree that getting props, directions, or wiring wrong can lead to some serious problems when you go to lift off for the first time. :-) So tonight I'm going to attempt to make the drawing of drawings to resolve this issue once and for all. I hung my quad on the wall and took a picture of "the real thing" (no diagrams here!). Then I imported it into publisher and worked it over. What you see below is what I ended up with. I hope it's right (???) and I hope it ends the agony of getting this wrong.

    ...Tiger
    1024 x 1024 - 102K
  • W9GFOW9GFO Posts: 4,010
    edited 2012-03-30 02:40
    An easy way (for me at least) to remember the prop rotations is to line up the props with the arms. The blades that are over the arms - the inside blades, will move away from the body. The front left and right blades will move forward away from the body and the rear right and left blades will move rearward away from the body. This is for a "x" configuration.
  • dmagnusdmagnus Posts: 271
    edited 2012-03-30 06:38
    Great drawing! All I would add is that the rotations, props and connections are the same for the Hoverfly Pro...
    Thanks,
    Don
  • DocThomasDocThomas Posts: 31
    edited 2012-03-30 09:29
    Thanks for the drawing. If I ever get time and a some cleaned up space I hope to get to use it.
  • JET-WJET-W Posts: 6
    edited 2012-03-30 09:54
    Excellent drawing !!! If this was part of the manual, it would of save me countless hours of wasted time.
  • DimitriDimitri Posts: 7
    edited 2012-03-31 11:31
    Wow! It is a lot of fun assembling ELEV8. I am novice in RC but okay with electronics. So far everything was clear and easy. Until I came to the point of programming ESC. So here is my question:
    Hoverfly Sport said that ESC has to be programmed for NIMH type of battery even if battery is LIPO. In the same time Parallax's manual refers to Turnigy ESC programming, which would make me select LIPO. Is it safe to select NIMH type?

    Thank you,
    Dimitri
  • TheGrueTheGrue Posts: 114
    edited 2012-03-31 12:08
    Dimitri wrote: »
    So here is my question:
    Hoverfly Sport said that ESC has to be programmed for NIMH type of battery even if battery is LIPO. In the same time Parallax's manual refers to Turnigy ESC programming, which would make me select LIPO. Is it safe to select NIMH type?

    I followed the HoverFly settings and have no issues.
  • Eggplant!Eggplant! Posts: 17
    edited 2012-03-31 14:14
    Ken Gracey wrote: »
    Yes - check the following:

    - Prop adapter to see that the shaft is not bent, causing an oscillation at higher RPM
    - Propeller for missing pieces as a result of a prior impact
    - Is the motor firmly attached to the base - can you pull the case up from the base?

    Holding it down on the ground, rev it up. Can you "see" a problem from that specific motor?

    If there's still a problem, I'd think the gain is probably too high.

    Ken Gracey

    Yup, it was the gain. Hitting the throttle too hard was causing oscillations. Thanks!
  • DimitriDimitri Posts: 7
    edited 2012-04-01 14:04
    TheGrue: Thank you for advising about ESC programming.

    So, I successfully assembled ELEV8. Hooray! The first attempt to fly was an expected disaster with 2 broken props. I love you "Crash Pack".

    I decided to try a benched approach and here how it looks. Even when it starts taking off it goes all over the place. HoverSport has an AP firmware and everything seems okay. I use DX8 and I configured it per Hoverfly Sport specs. I don't have Ultrasonic sensor yet, so I am not using altitude hold.

    Here is a video of how it takes off my table:

    I assume that holding nylon treads affect Hoverfly logic, so copter goes all over the place. However, even when it takes off it starts tilting before nylon threads are stretched.

    Any suggestions are really appreciated.

    Dimitri
  • Cats92Cats92 Posts: 149
    edited 2012-04-01 14:43
    Hello Dimitri,

    I met something like that when beginning.

    And wrote some suggestions (see page 52 of this thread).

    If you are a total beginner try to find somebody to help you on the field and use a flight simulator on your PC.

    Jean Paul
  • DimitriDimitri Posts: 7
    edited 2012-04-01 15:20
    Cats92 wrote: »
    Hello Dimitri,

    I met something like that when beginning.

    And wrote some suggestions (see page 52 of this thread).

    If you are a total beginner try to find somebody to help you on the field and use a flight simulator on your PC.

    Jean Paul

    Thank you, Jean Paul:

    I will check everything again. I already ordered a flight simultor. It just very hard to wait for the similator to arrive when just such toy is assebled and waiting for me.

    Dimitri
  • JET-WJET-W Posts: 6
    edited 2012-04-02 15:35
    Hi Everyone,

    I see you guys mentioned about setting the gain on the Throttle to 35% to start out , then 50% and up as you get more experience. I use a spectrum DX7s. When I set the Gain at 35%. One of the Motor does not spin, (The back motor the CCW one), That particular ESC just keep makes a repeatitive beeping sound every second. The other 3 motors are okay. However, When I set the Gain at 50%, there was no problem, All the motors are find and the Elev8 flys okay. Does anyone have a idea? Thanks.
Sign In or Register to comment.