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Fiber Optic servo extension

Forgues-Research

Forgues-Research

150cc
stangflyer said:
Please read again. You are partially correct in the operation of the SF. The board supplies a constant non interrupted 5.0 volts to the rx. (Nominally) However, the board isolates the rx. signal through filters and thus there is absolutely no chance of feed back from the signal lead to rx. The board then supplies exact supplied voltage to the servos of which are plugged into the board. At least this is my understanding from Bob Ritchie of Smart Fly. I have been using SF boards on every giant scale airframe I've ever owned for the last seven years. As for a servo dumping, the redundancy is designed as a back up insurance policy. I may be incorrect, however I believe...(not certain) they are designed with over amp protection. Something I may need to discuss with Bob. At any rate, Roger's system is the most secure I've seen to date. And yes...adding a power expander in place of a servo buss would absolutely be the most robust and bullet proof system I can think of.
Click to expand...
send me your email address please or even phone number
 
acerc

acerc

640cc Uber Pimp
stangflyer said:
Please read again. You are partially correct in the operation of the SF. The board supplies a constant non interrupted 5.0 volts to the rx. (Nominally) However, the board isolates the rx. signal through filters and thus there is absolutely no chance of feed back from the signal lead to rx. The board then supplies exact supplied voltage to the servos of which are plugged into the board. At least this is my understanding from Bob Ritchie of Smart Fly. I have been using SF boards on every giant scale airframe I've ever owned for the last seven years. As for a servo dumping, the redundancy is designed as a back up insurance policy. I may be incorrect, however I believe...(not certain) they are designed with over amp protection. Something I may need to discuss with Bob. At any rate, Roger's system is the most secure I've seen to date. And yes...adding a power expander in place of a servo buss would absolutely be the most robust and bullet proof system I can think of.
Click to expand...
I use Smart-fly as well, love their stuff. They do offer the buffers, the 5 amp, the isolation, etc., and it is by far better than nothing. My point is, there is still the risk of feed back however minimal it may be, any electrical connection harbors such risk. But with Rogers fiber optic separation there is no risk of feed back. If you use the fiber optic kill with the Smart-Fly board you know exactly how separate it is, no electrical connection to the Rx, no chance of fb.
I have seen some of your birds since you joined here, like myself you have some big and expensive aircraft, and like myself I am sure you know every time we leave the ground those minimal risk I speak of are in the back of your mind as well. I personally like the idea of eliminating them.
 
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Forgues-Research

Forgues-Research

150cc
the reason I went from one complete board to individual extensions is cost, not everyone are prepared to pay for the complete board system ,
I can still do the complete board system and I have reworked them to be even more reliable,
 
stangflyer

stangflyer

I like 'em "BIG"!
Forgues-Research said:
another video made earlier

Click to expand...

The more I watch your video and weigh the advantages vs. the possible weak links of our current systems, the more I am considering this system for my project next year.

Is there any risk of degradation of signal possible with longer fiber optic cables? As in roughly 120 inches.

With a three or four aileron servo setup, would the encoders and decoders be singular in design? Or would they be incorporated within one another? As in, a single board of one or a single board of "x" amount required?

With removable stabs and wing panels, how is the system designed to facilitate quick plug in access? (Forgive this question if you've previously answered it)

With a 15-17 servo system, what size battery, i.e....mah rating would be necessary for the encoders/decoders required?

And finally, what would a forecast of projected cost for such a system be?
 
Forgues-Research

Forgues-Research

150cc
stangflyer said:
The more I watch your video and weigh the advantages vs. the possible weak links of our current systems, the more I am considering this system for my project next year.

Is there any risk of degradation of signal possible with longer fiber optic cables? As in roughly 120 inches.

With a three or four aileron servo setup, would the encoders and decoders be singular in design? Or would they be incorporated within one another? As in, a single board of one or a single board of "x" amount required?

With removable stabs and wing panels, how is the system designed to facilitate quick plug in access? (Forgive this question if you've previously answered it)

With a 15-17 servo system, what size battery, i.e....mah rating would be necessary for the encoders/decoders required?

And finally, what would a forecast of projected cost for such a system be?
Click to expand...

Is there any risk of degradation of signal possible with longer fiber optic cables? As in roughly 120 inches.
To your first question, as far as degradation of the light source, no your looking at a possible 120 inches , and these will not degrade for at least 100 feet.
Also for a peace of mind, I have tested the FO cable by pinching it tight without loss of signal, (not recommended) but they will still work.

With a three or four aileron servo setup, would the encoders and decoders be singular in design? Or would they be incorporated within one another? As in, a single board of one or a single board of "x" amount required?
If you use one channel per servo, lets say for both ailerons, meaning 6 servos , you would need 6 channels , in turn 6 encoders and 6 decoders. Unless you are using Y connectors , which I doubt you would .
From the RX, these are 6 individual units, but it can be as a single board with 6 encoders as you have seen in the 9 channel single board , the number is not important.
For the decoders, it would be impractical to have them bunched up in two 3 units for each wing, but it can be done.

With removable stabs and wing panels, how is the system designed to facilitate quick plug in access?
Good question, for the wings, the encoders can remain in the wing root cavity if one desires , and simply have an extension from the RX to the wing plug in. plus the power wires, Here for 3 servos, one larger wire to feed back into the wing and seperate into 3 for the 3 decoders.
For the Stab since they are further from the RX , we have fiber optic inline connectors for this and of course you need connectors for the power.

With a 15-17 servo system, what size battery, i.e....mah rating would be necessary for the encoders/decoders required?
First you need a battery for the RX which also powers the encoders . At 17 servo encoders @ roughly 20 ma ea. plus the RX at roughly 20 ma, that gives a total of 360 ma. and for this I would use about 1000 ma Lipo or which ever chemical battery you are using. You can go bigger here if you wish, Remember there are no servos plugged in this part.
For the servos/decoders, use whatever battery you had intentions on using in the first place, the decoders takes less power then the encoders , so less then 15 ma each.

And finally, what would a forecast of projected cost for such a system be?

For projected cost I will contact you privately since we are not allowed to talk money in an open forum.
 
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