Need help with 3D CAD linkage idea
#1
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Need help with 3D CAD linkage idea
I'm interested in utilizing a floating bell-crank system for four in-line hard connected servos. I did some rough schetchs and believe its viable. I'm looking for someone willing to draw out the idea and put it to work in a 3D simulation and if need be manipulate the numbers to see if it make sense or is a waste of time...
Anybody with the skills interested???
Anybody with the skills interested???
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RE: Need help with 3D CAD linkage idea
The overwhelming likelyhood is I can do that. I'm not to hip on animation, but the 3D CAD part I have a great grip on. Send me an e-mail and we talk about it more after I have a better idea of what you are looking for.
#4
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RE: Need help with 3D CAD linkage idea
Thanks for your offer, but I guess it won't work. I dug up some wore out 2721 servos and linkages and gave it a shot. Seems no matter how configure the linkage, binding occurs when I lock-up one servo. I was hoping I could come up with something that would allow the other servos to work around a dead servo. I would have settled for reduced throw as well. [:@] I'll have to think a little harder.
#7
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RE: Need help with 3D CAD linkage idea
Thanks for the input. I am familiar with the two servo floating systems in play; I was after a three or four servo inline setup as configured in the picture I provided. I may have to go with something like the two servo setup in the second set of pictures. More thinking I guess.[&:]
The reason behind the need is pretty basic. If one of the servos in a four ganged servo locks up for whatever reason, several things can happen. The stalled servo can and will consume several amps on its own, not to mention the other three working servos may try and beat the stalled servo down, consuming even more power. Or maybe the servo dies and all is well no mechanical resistance or then again if the gear train is damaged something similar to my first scenario would be in play. In any event it’s not a pretty picture. I nearly lost a new 40% Carden Edge when a servo died at full deflection and locked up, two other servos were beat up in the process, but we got the Edge down with all most no damage. Have you ever flown a 40% model with full rudder deflection to the tarmac? The Edge was in a full crab and it took several passes to get the model lined up on the runway. Actually the angle of approach was so sever due to the crabbed stall that that it took an approach from an extreme corner of the field to finally end up on the runway.
The reason behind the need is pretty basic. If one of the servos in a four ganged servo locks up for whatever reason, several things can happen. The stalled servo can and will consume several amps on its own, not to mention the other three working servos may try and beat the stalled servo down, consuming even more power. Or maybe the servo dies and all is well no mechanical resistance or then again if the gear train is damaged something similar to my first scenario would be in play. In any event it’s not a pretty picture. I nearly lost a new 40% Carden Edge when a servo died at full deflection and locked up, two other servos were beat up in the process, but we got the Edge down with all most no damage. Have you ever flown a 40% model with full rudder deflection to the tarmac? The Edge was in a full crab and it took several passes to get the model lined up on the runway. Actually the angle of approach was so sever due to the crabbed stall that that it took an approach from an extreme corner of the field to finally end up on the runway.
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RE: Need help with 3D CAD linkage idea
That's way beyond me. I get intimidated just looking at planes that big fly. Certainly makes sense that planes that big and that expensive should incorporate redundency systems.
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RE: Need help with 3D CAD linkage idea
give some thought to using 2 double servo rig's like the photo I posted. In a double flying bellcrank arangment. I have no Idea if it would work or not. But that's what poped into my head looking at your pictures. Another words have two double bellcrank setups side by side, then atatched at a second flying bell crank to hook the pair together. Does this make sence?????
#10
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RE: Need help with 3D CAD linkage idea
Feed the output of one flying bellcrank in as the input (as if a single servo) to the next flying bellcrank.
Don't try mounting the "flying" bellcranks ON the servo arms. (because then... they aren't flying, they are mixing.)
Don't try mounting the "flying" bellcranks ON the servo arms. (because then... they aren't flying, they are mixing.)