High amp 5955 servos
07-12-2007, 10:10 PM
#76
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RE: High amp 5955 servos
My Hitec 5985s with only a arm on them run between 0.13 and 0.16...gently sweeping...however when moved suddenly they pull 0.32 almost double.
Just was testing them to see if they had any problems and they are very consistent.
Havent tested the 5955s yet.
Just was testing them to see if they had any problems and they are very consistent.
Havent tested the 5955s yet.
07-13-2007, 05:25 AM
#77
RE: High amp 5955 servos
ORIGINAL: Silversurfer
No prob. Hope all works out well. For the record, the 4 amp number I provided some time back for the connectors was obtained from Cermark in discussions I had with them about their products. Hope that helps with some of the figures you may sometime need.
Pat
No prob. Hope all works out well. For the record, the 4 amp number I provided some time back for the connectors was obtained from Cermark in discussions I had with them about their products. Hope that helps with some of the figures you may sometime need.
Pat
Extension leads have always worried me to a certain extent, the quality of the plugs and the gauge of the wire left me feeling a bit nonplussed, Hitec servos tend to have a higher gauge of wire compared with others out there, so I obtain an equivilant three core wire and cut splice and solder all the extension I need straight onto the servo, this also enables the fine tuning of the length, so that you don't get excess flapping around or heaven forbid bunched up in the fus, also it means you can run the cables through a grommet inside the fus installed in a former makes a very neat installation.
Mike
07-13-2007, 08:35 AM
#78
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RE: High amp 5955 servos
I hear you about the cable length. I can't stand to see a bunch of wires coiled up somewhere or laying around loose. Wasted length compounds the amperage and voltage drop issues as well. I still use mostly Cermark products since they use a 22ga. wire and gold plated connectors. One of the few extension and switch manufacturers where I have not ever had a problem with a product. Being short on time I usually cut an extension to what it needs to be and hard wire it into the servo lead. If I was to take an extra 5 minutes or so I could likely make my own and pin them out.
A little food for thought about all the high torque sevos we are using. Like yourself I use 8611's or 5955's in my planes. Figure that my planes come in anywhere from 16 to 27 pounds and fly HARD for 15 minutes at a time or so. Now what I work with has a 10' span, weighs in over 40 pounds, uses spoilerons and ruddervators, flies for 15 hours or more, goes through thunderstorms, and uses only Futaba metal gear mini digitals for 100 hours or so before tossing them, almost all of them with useful life remaining.
Makes me wonder just how much overkill we have built into our aerobats with the servos.
A little food for thought about all the high torque sevos we are using. Like yourself I use 8611's or 5955's in my planes. Figure that my planes come in anywhere from 16 to 27 pounds and fly HARD for 15 minutes at a time or so. Now what I work with has a 10' span, weighs in over 40 pounds, uses spoilerons and ruddervators, flies for 15 hours or more, goes through thunderstorms, and uses only Futaba metal gear mini digitals for 100 hours or so before tossing them, almost all of them with useful life remaining.
Makes me wonder just how much overkill we have built into our aerobats with the servos.
07-13-2007, 09:48 AM
#79
RE: High amp 5955 servos
the 8711 can draw alot more power, but I am hearing alot of 35% folks using one on the rudder in place of two of anything else.
The bottom line is a robust power delivery system and minimizing plugs on servo wires, and min length. I also like pull pull for that reason. It plugs directly into the receiver.
for ailerons, on the TBM website, Gene says one servo can be used on 35% planes if the aileron is sheeted. works for me.
The plugs can take alot of spiked current, if you could test them to failure on a .1 second burst, I bet they would carry 20 amps or so. who knows for sure. tough test. Its the sustained voltage drop that gets you or brown out as we call it.
I have noticed the AR7000 is more sensitive to voltage drops. QQ had an AR9000 in his python. They attributed the real culprit to be the 7.5 amp regulator he had being too light. makes total sense to me too. Twin 7.5's fixed that easy. Most recievers can handle the large amperage on the bus, so thats why 2 or 3 plugs on power is good. I like the idea of powering a match box, but the receiver can handle the load if you can get it into the receiver in a redundant manner ie..multiple plugs or sources.
my opinion only.
Im not afraid of the 8711. It is a kick butt 35% rudder servo. Probably overkill for other things. It can replace 2 servos of anything else, simplifying setup, eliminating a matchbox.
The bottom line is a robust power delivery system and minimizing plugs on servo wires, and min length. I also like pull pull for that reason. It plugs directly into the receiver.
for ailerons, on the TBM website, Gene says one servo can be used on 35% planes if the aileron is sheeted. works for me.
The plugs can take alot of spiked current, if you could test them to failure on a .1 second burst, I bet they would carry 20 amps or so. who knows for sure. tough test. Its the sustained voltage drop that gets you or brown out as we call it.
I have noticed the AR7000 is more sensitive to voltage drops. QQ had an AR9000 in his python. They attributed the real culprit to be the 7.5 amp regulator he had being too light. makes total sense to me too. Twin 7.5's fixed that easy. Most recievers can handle the large amperage on the bus, so thats why 2 or 3 plugs on power is good. I like the idea of powering a match box, but the receiver can handle the load if you can get it into the receiver in a redundant manner ie..multiple plugs or sources.
my opinion only.
Im not afraid of the 8711. It is a kick butt 35% rudder servo. Probably overkill for other things. It can replace 2 servos of anything else, simplifying setup, eliminating a matchbox.
07-13-2007, 11:02 AM
#80
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RE: High amp 5955 servos
The 8711 is a great servo for a high torque application. The only real issue I have with it is that it still has the same type of gear train as the 8611, which is well documented and noted to have fast gear wear. Something I've experienced myself many times.
As you've noted, excersizing a little thought and care in the system electricals will eliminate most if not all current issues.
As you've noted, excersizing a little thought and care in the system electricals will eliminate most if not all current issues.
07-13-2007, 05:39 PM
#81
RE: High amp 5955 servos
ORIGINAL: sinergy
Troybuiltmodels did a test showing the new 8711 can draw 4.5amps on it's own. That is the biggest draw back to their new servo. The 5955 will do half of that stalled. Personally I would rather run 2 5955s and take less power than one 8711 working hard.
Not only are you buying the most expensive servo out there.. you now really need a power exapnder to use it properly.
Troybuiltmodels did a test showing the new 8711 can draw 4.5amps on it's own. That is the biggest draw back to their new servo. The 5955 will do half of that stalled. Personally I would rather run 2 5955s and take less power than one 8711 working hard.
Not only are you buying the most expensive servo out there.. you now really need a power exapnder to use it properly.
True, the 8711 can draw a lot of amps - if you stall it. But, for example, if you use it as a direct replacement for a 5955 on, say, the rudder of a 35% plane, chances are VERY GOOD you will 1) notice a difference in rudder authority, and 2) the 400 oz.in. (assuming their data is accurate, which it should be since the 8611 produces their rated torque)8711 will not stall on you like the 220-250 oz.in. (based on more than one independent test) 5955 most likely did on certain maneuvers, and therefore will not be drawing much more amps. Another thing to consider is that the 5955 draws around 2.5 amps to produce its independently tested roundabout figure of 250oz.in. - that's 1 amp per 100oz.in. You say you would rather have two of them than one 8711, but in order for them to put out 400 oz.in, they will likely draw 4 amps together, assuming perfect geometry when bundling them up, too. Then, almost in the same sentence, you said the 8711 is too expensive - how much will two 5955's run you? Not to mention the $10+ for an additional servo arm...
Of course, you also just added another 3 ounces per control surface, too, assuming you actually did run two 5955's instead of one 8711.
Now, don't get me wrong - I LOVE my 5955's! My next plane (35% 260) will have them on every control surface - except the rudder - a single 8711 is going there. It's a good 100-150 ounces of extra torque over the 5955, lighter and simpler than two servos, and around $60 cheaper.
07-14-2007, 06:43 AM
#83
RE: High amp 5955 servos
FWIW:
if you are looking for power - be prepared to draw up to an amp for each 100 " of torque. That is no secret.
One "secret" not often mentioned is that a steady 4 amps is MORE than ANY of the stock wire ends likes to see. They get quite warm - that IS the ragged asted edge of flow thru those crimped connectors -
So - two 200 oz servos have a much better chance of giving the full power -IF each wire has a full source of power.
--another secret-- the momentary voltage depression possible with either combo can be at least the 1 amp per 100 in ozs.
If you use resistor type regulators in your system - make sure you have them sized so they don't get hot
as they heat - current flow drops .
------------ To the entire system------------------
This is where the fit hits the shan.
before you get wild eyed about bigger servos - make sure your setup actually feeds full power to the servo.
measure it
small voltmeters are readily available which plug into any servo pin outlet .
when cram the sticks back n forth the voltage in the entire system will drop irrespective of which servo is drawing the current .
The best power I have seen which holds up under really big servos, is either latest sub C 4500+ Nimh or the A123 cells
I won't use regs in this system.
my choice -
if your system does not heat and does the job you want - then no problem.
if you are looking for power - be prepared to draw up to an amp for each 100 " of torque. That is no secret.
One "secret" not often mentioned is that a steady 4 amps is MORE than ANY of the stock wire ends likes to see. They get quite warm - that IS the ragged asted edge of flow thru those crimped connectors -
So - two 200 oz servos have a much better chance of giving the full power -IF each wire has a full source of power.
--another secret-- the momentary voltage depression possible with either combo can be at least the 1 amp per 100 in ozs.
If you use resistor type regulators in your system - make sure you have them sized so they don't get hot
as they heat - current flow drops .
------------ To the entire system------------------
This is where the fit hits the shan.
before you get wild eyed about bigger servos - make sure your setup actually feeds full power to the servo.
measure it
small voltmeters are readily available which plug into any servo pin outlet .
when cram the sticks back n forth the voltage in the entire system will drop irrespective of which servo is drawing the current .
The best power I have seen which holds up under really big servos, is either latest sub C 4500+ Nimh or the A123 cells
I won't use regs in this system.
my choice -
if your system does not heat and does the job you want - then no problem.
07-14-2007, 08:10 AM
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RE: High amp 5955 servos
ORIGINAL: bodywerks
I'm sorry, that just makes no sense to me.
True, the 8711 can draw a lot of amps - if you stall it. But, for example, if you use it as a direct replacement for a 5955 on, say, the rudder of a 35% plane, chances are VERY GOOD you will 1) notice a difference in rudder authority, and 2) the 400 oz.in. (assuming their data is accurate, which it should be since the 8611 produces their rated torque)8711 will not stall on you like the 220-250 oz.in. (based on more than one independent test) 5955 most likely did on certain maneuvers, and therefore will not be drawing much more amps. Another thing to consider is that the 5955 draws around 2.5 amps to produce its independently tested roundabout figure of 250oz.in. - that's 1 amp per 100oz.in. You say you would rather have two of them than one 8711, but in order for them to put out 400 oz.in, they will likely draw 4 amps together, assuming perfect geometry when bundling them up, too. Then, almost in the same sentence, you said the 8711 is too expensive - how much will two 5955's run you? Not to mention the $10+ for an additional servo arm...
Of course, you also just added another 3 ounces per control surface, too, assuming you actually did run two 5955's instead of one 8711.
Now, don't get me wrong - I LOVE my 5955's! My next plane (35% 260) will have them on every control surface - except the rudder - a single 8711 is going there. It's a good 100-150 ounces of extra torque over the 5955, lighter and simpler than two servos, and around $60 cheaper.
ORIGINAL: sinergy
Troybuiltmodels did a test showing the new 8711 can draw 4.5amps on it's own. That is the biggest draw back to their new servo. The 5955 will do half of that stalled. Personally I would rather run 2 5955s and take less power than one 8711 working hard.
Not only are you buying the most expensive servo out there.. you now really need a power exapnder to use it properly.
Troybuiltmodels did a test showing the new 8711 can draw 4.5amps on it's own. That is the biggest draw back to their new servo. The 5955 will do half of that stalled. Personally I would rather run 2 5955s and take less power than one 8711 working hard.
Not only are you buying the most expensive servo out there.. you now really need a power exapnder to use it properly.
True, the 8711 can draw a lot of amps - if you stall it. But, for example, if you use it as a direct replacement for a 5955 on, say, the rudder of a 35% plane, chances are VERY GOOD you will 1) notice a difference in rudder authority, and 2) the 400 oz.in. (assuming their data is accurate, which it should be since the 8611 produces their rated torque)8711 will not stall on you like the 220-250 oz.in. (based on more than one independent test) 5955 most likely did on certain maneuvers, and therefore will not be drawing much more amps. Another thing to consider is that the 5955 draws around 2.5 amps to produce its independently tested roundabout figure of 250oz.in. - that's 1 amp per 100oz.in. You say you would rather have two of them than one 8711, but in order for them to put out 400 oz.in, they will likely draw 4 amps together, assuming perfect geometry when bundling them up, too. Then, almost in the same sentence, you said the 8711 is too expensive - how much will two 5955's run you? Not to mention the $10+ for an additional servo arm...
Of course, you also just added another 3 ounces per control surface, too, assuming you actually did run two 5955's instead of one 8711.
Now, don't get me wrong - I LOVE my 5955's! My next plane (35% 260) will have them on every control surface - except the rudder - a single 8711 is going there. It's a good 100-150 ounces of extra torque over the 5955, lighter and simpler than two servos, and around $60 cheaper.
I appreciate you taking the time to analyze my thoughts... but if you look at the bigger picture you will have more power with 2 5955s and in the long run save money.
How? Easy... 1 8711 is $140 a gear set is $36. 2 5955s are $178. I fly 300-600 flights a year in one of my planes.. how many gear sets do you think I will have to buy with that JR? I would bet atleast one if not 2. So that 1 8711 cost me $176 for that first year and atleast $36 every year after that.
My other thought (althought I may not be correct) is that if you have 2 servos working together they are not going to draw as many amps each as 1 servo working by itself on that same surface, if setup correctly. Therefore while that one 8711 peaks into 5 amps and quickly goes down to 4.2.. the 2 5955s hits less than 2.5 ( because they are woprking together and not as hard) and drops.. You then have more torque for less amp draw. Maybe I am wrong.
07-14-2007, 09:19 AM
#86
RE: High amp 5955 servos
where you may be wrong -- is that no matter how you do it - the same power at the flight surface is required and same power = same current
the catch ?
efficiencies .
so those two servos have twice the wire (current capacity- the gear trains -motor types board design -on and on make up variables we can only guess at .
the only meaningful test is to ask each setup to lift an identical load ( a load similar to actual use) and measure current and voltage drop too.
I have no idea as to which would win.
I would bet tho that the dual setup would survive the heat better as the total heat load would be /2.
the catch ?
efficiencies .
so those two servos have twice the wire (current capacity- the gear trains -motor types board design -on and on make up variables we can only guess at .
the only meaningful test is to ask each setup to lift an identical load ( a load similar to actual use) and measure current and voltage drop too.
I have no idea as to which would win.
I would bet tho that the dual setup would survive the heat better as the total heat load would be /2.
07-14-2007, 09:32 AM
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RE: High amp 5955 servos
bodywerks - excuse what you may perceive as sarcasm - -
Ask the JR/Horizon engineering dudes, *and* QQ how happy THEY are with 8711 current draw on the regulator that **WAS** being used in QuiQues' Python at SEFF. There ain't NUTHIN' anecdotal about that. Those suckers drew more current, in total, than the overheating and under-sized regulator could provide, so HIS airplane went to sleep.
Good enough for me.
But then, I've been running low impedance and High capacity NiMh 5 cell packs for a few years. I almost lost a good pattern airplane once to "current fade", and learned.
Next up are un-regulated A123's, with dual input connectors to the RX buss. THOSE ain't gonna voltage *or* current fade.
Ask the JR/Horizon engineering dudes, *and* QQ how happy THEY are with 8711 current draw on the regulator that **WAS** being used in QuiQues' Python at SEFF. There ain't NUTHIN' anecdotal about that. Those suckers drew more current, in total, than the overheating and under-sized regulator could provide, so HIS airplane went to sleep.
Good enough for me.
But then, I've been running low impedance and High capacity NiMh 5 cell packs for a few years. I almost lost a good pattern airplane once to "current fade", and learned.
Next up are un-regulated A123's, with dual input connectors to the RX buss. THOSE ain't gonna voltage *or* current fade.
07-14-2007, 08:19 PM
#88
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RE: High amp 5955 servos
""Next up are un-regulated A123's, with dual input connectors to the RX buss. THOSE ain't gonna voltage *or* current fade.""""
Bob, I am running a 2 cell pack in my Extreme Flight 88. I only have one 5955 for rudder and 5945's on the rest of flight. I have the battery on a Smart Fly[EDIT Smart Fly Switch] with the two output leads to the reciever. Although my FAUP 1950 served well it is being retired. Five hard 10 minute flights today didn't seem to want to put a dent in these batteries and they did not heat up like the FAUP did from all of the power draw.
Talking about amps watch thes batteries in DEEP CELL ACTION
http://www.youtube.com/watch?v=GDHJNG2PngQ
Bob, I am running a 2 cell pack in my Extreme Flight 88. I only have one 5955 for rudder and 5945's on the rest of flight. I have the battery on a Smart Fly[EDIT Smart Fly Switch] with the two output leads to the reciever. Although my FAUP 1950 served well it is being retired. Five hard 10 minute flights today didn't seem to want to put a dent in these batteries and they did not heat up like the FAUP did from all of the power draw.
Talking about amps watch thes batteries in DEEP CELL ACTION
http://www.youtube.com/watch?v=GDHJNG2PngQ
07-25-2007, 08:22 AM
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RE: High amp 5955 servos
I have two fromeco regs and they heat up with 3+ amps sustained thru each. I made my own custom heatsinks and now they provide 10+ amps sustained each.
In our application we rairly use high currents for long sustained periods, short bursts are more typical which lets thing cool down in between.
Fromoco uses a Sharp linear reg and they generate more heat as a by product verses a switcher design.
You also have to consider the current rating for each connector from the reg that plugs into the RX.
I am using 7.4vlipos 4000mah as source and using a adjustable resistive load to test regs.
I have my fromoco's in a 36% Katana which run 8 Hs5955TG's + smoke pump + 2 other servos, as dual supplies with 4 power leads(2 each) into a 5014 RX.
I am looking at making my own system using an off the shelf switcher with following specs.
4.5 to 15v input, 4.8-6.8v output and true 18 amps sustained output. All this fits in the space of 1.5x0.55x0.6 inches.
I currently have some under testing and looking very good with exceptional high - low transiant current responses, solid vout and less than 50mvpp noise.
In our application we rairly use high currents for long sustained periods, short bursts are more typical which lets thing cool down in between.
Fromoco uses a Sharp linear reg and they generate more heat as a by product verses a switcher design.
You also have to consider the current rating for each connector from the reg that plugs into the RX.
I am using 7.4vlipos 4000mah as source and using a adjustable resistive load to test regs.
I have my fromoco's in a 36% Katana which run 8 Hs5955TG's + smoke pump + 2 other servos, as dual supplies with 4 power leads(2 each) into a 5014 RX.
I am looking at making my own system using an off the shelf switcher with following specs.
4.5 to 15v input, 4.8-6.8v output and true 18 amps sustained output. All this fits in the space of 1.5x0.55x0.6 inches.
I currently have some under testing and looking very good with exceptional high - low transiant current responses, solid vout and less than 50mvpp noise.
07-27-2007, 06:55 PM
#92
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RE: High amp 5955 servos
Alright guys.. I just bought my first larger scale plane. GP 232 27%. My plan is to put five 5955's. I have a couple regulators. A 5.1 Jacio perfect harness switch and a Duralite regulator. Will either of those work so I don't have to buy another one? Or just don't even use a regulator since I'm using a 4.8v battery subC? Also? Are you guys saying it's not safe to plug these five 5955's and a sixth throttle servo into the same reciever using one 4200nimh? Another question.. I need to use some servo extensions. Are any better or different from others? Thanx.
07-27-2007, 07:06 PM
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RE: High amp 5955 servos
ORIGINAL: RadarController
Alright guys.. I just bought my first larger scale plane. GP 232 27%. My plan is to put five 5955's. I have a couple regulators. A 5.1 Jacio perfect harness switch and a Duralite regulator. Will either of those work so I don't have to buy another one? Or just don't even use a regulator since I'm using a 4.8v battery subC? Also? Are you guys saying it's not safe to plug these five 5955's and a sixth throttle servo into the same reciever using one 4200nimh? Another question.. I need to use some servo extensions. Are any better or different from others? Thanx.
Alright guys.. I just bought my first larger scale plane. GP 232 27%. My plan is to put five 5955's. I have a couple regulators. A 5.1 Jacio perfect harness switch and a Duralite regulator. Will either of those work so I don't have to buy another one? Or just don't even use a regulator since I'm using a 4.8v battery subC? Also? Are you guys saying it's not safe to plug these five 5955's and a sixth throttle servo into the same reciever using one 4200nimh? Another question.. I need to use some servo extensions. Are any better or different from others? Thanx.
4200mah will be huge capacity. I have exactly the same airplane, same 5955's all round, running a 2300mah pack, plenty of flight time.
Whatever extension you buy should be crimped, gold-plated contacts, at least 22ga. 20ga is better. Many use Maxx Products or Cermark. Always JR Heavy Duty. And others.
07-27-2007, 08:57 PM
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RE: High amp 5955 servos
Radar, those servo's are complete overkill for that aircraft! There is no need for that much servo power in an aircraft that weigh's in at 12lbs,if any dought,come over to Daytona and I will let my son prove that to you.
Donnie
Donnie
07-27-2007, 09:28 PM
#95
RE: High amp 5955 servos
The 20 G extensions are fine----Connectors are not.In my 40% using 6' long extensions, have reduced connectors to ONLY one.All other Soldered.Measured a malfunctioning Extension of 3.5 feet length causing servo jitter and the Micro Ohm meter showed a Resistance of 70 Milliohms v/s new of 9 Milliohms-----After thoroughly cleaning the 2 connectors with Methanol the Resistance FELL to 12 Milliohms and Jitter gone----CUT OFF the connectors and the same extension measured only 8 Milliohms. ---- .In time even if unused connectors Oxidise and gain Resistance.
07-27-2007, 09:35 PM
#96
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RE: High amp 5955 servos
Another reason to use the gold plated connectors. Gold does not tarnish.
As for the servo overkill thing, I agree but there's a caveat. If someone is looking to purchase equipment that they can move up with the 5955 would be a good example. Though it may be well more servo than needed in one plane, when moving up later to a 28 to 35% plane then it would be just what the doctor ordered. In this situation the owner would not have to buy servos twice. Sort of like buying a 9 or 10 channel right off the bat instead of buying a 4, then 6, then 9 channel radio. It's cost effective to buy the good stuff once instead of average stuff once then the good stuff later.
As for the servo overkill thing, I agree but there's a caveat. If someone is looking to purchase equipment that they can move up with the 5955 would be a good example. Though it may be well more servo than needed in one plane, when moving up later to a 28 to 35% plane then it would be just what the doctor ordered. In this situation the owner would not have to buy servos twice. Sort of like buying a 9 or 10 channel right off the bat instead of buying a 4, then 6, then 9 channel radio. It's cost effective to buy the good stuff once instead of average stuff once then the good stuff later.
07-28-2007, 05:52 AM
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RE: High amp 5955 servos
very true,if looking ahead and planning for this plane to expire in the near future and just have to transfer equipment, this would work just fine.
Donnie
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07-28-2007, 06:16 AM
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RE: High amp 5955 servos
And the other reason I recommend 5955's, even if "overkill" for a persons' application. No maintenance. Gears hold up nearly forever, apparently. At least, I've not read a SINGLE post in here about "gear slop" or "gear wear" or "gear replacement" in the 5955's. That lowers the cost of operation a bunch over the life of the servo. So, yes, an individual servo can go in and out of several airframes.
Also saves money standardizing arms, extensions, etc.
Just my experience and opinion on it.
Also saves money standardizing arms, extensions, etc.
Just my experience and opinion on it.
07-28-2007, 07:59 AM
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RE: High amp 5955 servos
Any why NOT buy them? For $89 or less, they are only a couple pennies more than any other metal gear servo, less teh Hitec 56xx series which I would shy away from anyway.
The UAV is a different animal... it doesn't have 3D control surfaces and I doubt it's ever on vertical downlines, etc... It has a more efficient cambered airfoil and smaller percentage control surfaces.
It's kinda like the difference between a 3D 40% and a large scale full-house glider... the glider is getting away with mni and micro servos, sometimes just glued in, and reaches speeds over double what a 40% Extra will. Size doesn't determine requirements, design does.
A little food for thought about all the high torque sevos we are using. Like yourself I use 8611's or 5955's in my planes. Figure that my planes come in anywhere from 16 to 27 pounds and fly HARD for 15 minutes at a time or so. Now what I work with has a 10' span, weighs in over 40 pounds, uses spoilerons and ruddervators, flies for 15 hours or more, goes through thunderstorms, and uses only Futaba metal gear mini digitals for 100 hours or so before tossing them, almost all of them with useful life remaining.
It's kinda like the difference between a 3D 40% and a large scale full-house glider... the glider is getting away with mni and micro servos, sometimes just glued in, and reaches speeds over double what a 40% Extra will. Size doesn't determine requirements, design does.
07-28-2007, 11:42 AM
#100
Senior Member
My Feedback: (1)
RE: High amp 5955 servos
Very true about the servo prices.
Our model designs are actually very poorly designed, with little attention to balancing the surfaces, rather antiquated hinging, variations in hinge gaps, an extremely flexible structure as a whole, and other items including a much weaker airframe. One thought to consider. A UAV will be using it's surfaces at a faster rate, much more frequently, at speeds that vary considerably, at a relatively greater vehicle weight. Gust loading due to thermal activity is rather high due to a requirmement to hold specific altitudes, for many continuous hours at a time. Agreed that straight down would normally be considered a terminal thing. I still contend that we all massively over powering our surfaces with servos far larger and stronger than they need to be.
Our model designs are actually very poorly designed, with little attention to balancing the surfaces, rather antiquated hinging, variations in hinge gaps, an extremely flexible structure as a whole, and other items including a much weaker airframe. One thought to consider. A UAV will be using it's surfaces at a faster rate, much more frequently, at speeds that vary considerably, at a relatively greater vehicle weight. Gust loading due to thermal activity is rather high due to a requirmement to hold specific altitudes, for many continuous hours at a time. Agreed that straight down would normally be considered a terminal thing. I still contend that we all massively over powering our surfaces with servos far larger and stronger than they need to be.