quadcopters are fun

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QUADCOPTERS ARE FUN

Advanced Quadcopter Design

Please Note! this wiki section is for those interested in constructing and possibly even

designing their own Quadcopter. For information on understanding how a multicopter works please go Here For information on how to build your own simple Quadcopter using kits or frames go

Here For information on building or setting up a copter for first Person View (FPV) go

Here

Motors, propellers and ESCs

For multi copters, motors, propellers and ESCs (speed controllers) are critical and have beenfailure prone in the past.

This E-Calc basedXcopter: motor - propeller - battery - ESC calculatorwill help you pick thebest parts for your copter.

Quadcopter design is featured here as they are the most wide spread and the

most versatile.

o But this information also applies to Hexacopter and Octocopter designs, eitherconventional or the coaxial Y and X types.

The brushless out-runner motors have to support the full weight of the coptercontinuously while turning at high speed.

o Hobby grade motors have often used inadequate Conrad type unsealedbearings which are good axially but not in thrust.

o And the motors are usually open frame to permit the greatest cooling butproviding little or no protection

o This has meant an unnecessarily high failure rate and very poor survival in wetor dusty conditions.

o The cheapest possible Chinese motor is never a good choice for somethingthat literally hangs in the air by its motor.

o The best motors have 2 or better 3 easily replaceable ABEC-7 bearings, RC

Tiger-Motor Pro series and KDE for instance.o Top motors are well ventilated, made with high temperature components and

coated and sealed for environmental protection.o The best motors like T-Motor and KDE have performance comparison charts,

these should be reviewed when designing a coptero You are best off selecting motor - prop - battery cell combinations that will

provide 10% or higher G/W efficiency at 50% throttle.o You should target you copter design weight so that it hovers at approximately

50% throttle for optimum efficiency and flight time.o Top motors can cost considerably more, but reliability, performance and

efficiency will be better and worth it in the long run.o

Low KV motors running on lower voltage (fewer cells) with large propellersare more efficient and provide longer flight times.
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o Selecting the best motor, propeller, battery set will enable you to build acopter with 20+ minute flight times including a camera.

o You can get 20+ minutes from 330 copters with 8 inch props to 700 copterswith 18 inch props depending on payload weight.

o It is very hard to get much more than 30 minutes of usable flight time from

any useful multi copter regardless of size.o For hobby grade components, 15 to 20 minute maximum flight times are a

more realistic goal.

ESCs are also very important:

o High quality ESCs are more reliable than cheap ones.o And ESCs need to be properly sized to ensure they can provide the maximum

current that is necessary.o Generally use the right size not over sized because they are more efficient if

operated in the appropriate range (and lighter).o Sufficient cooling is also very important especially for Heavy Lift copters, and

the ESCs may need to be placed in the air stream.o

For small to medium QuadCopters there are four in one ESCs in the 20 - 30Amp size range with several advantages.

o They eliminate the need for a power distribution plate or block and all theattendant wiring.

o The considerable reduction in DC wiring results in less magnetometer(compass) interfering DC EMF radiation.

o They can often be conveniently installed tidily in the centre of the copterframe.

o The 20 and 25 amp ones work with 3 or 4 cell Li-Po batteries and the 30 ampone works with 3 to 6 cell batteries.

o They have a built in aluminium heat sink plate on one side (which you canaugment with a finned heat sink if necessary).

o You can use a thin layer of Fujik silicone thermal glue to attach a finned heatsink if one is needed.

o They generally have higher reliability than individual ESCs and are reasonablypriced.

Larger diameter slower turning propellers are normally a lot more efficient than

smaller, faster ones.o But there are limits and drawbacks:o Trying to turn too large a prop for a given motor can cause it to overheat so

motors usually have a maximum prop size.o

Also, really large, slow props can reduce the responsiveness of the multicopter and even cause it to oscillate in the air or vibrate.o Unless taken to extremes these difficulties are not usually significant and can

be compensated for by various means.o And you can always drop the diameter an inch if the handling characteristics

or motor stress are not what you want.o There are also different designs of propellers and for larger ones turning at

slower speeds design is especially critical.o Carbon fibre designs with cupped blades that are wider at the hub and

narrower at the tip are best for 14 inch and larger.o Propellers 14 inch and under can be of more conventional design with a wider

than normal blade and of plastic or CF.


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o Often motors are charted withspecific propellers and these are certainly the

best starting point for optimum performance.o T-Motor is considered a premium

prop, but good results have been obtained with

RC-Timer and Tarot in the large tapered props.o APC, DJI, Gem Fan, RC Drones

and Graupner all produce good props in the 14inch and under category.

Professional Grade Power System for large

Quadcopters (28 inch Propellers)

The Tiger motor U8 Pro Series motor is currently top of the line for a commerciallyavailable (large) copter motor.

o It features environmentally protected, closed construction and easily

replaceable bearings.

They have very high quality two piece 27, 28 and 29 inch carbon fibre propellers forthem as well.

And a top quality 70 AMPESC (speed controller) to gowith it.

U8 Pro T-Motor $300.00, 28inch carbon fibre Props $370.00 a pair, 70 Amp Pro ESC $110.00 @ four each =$2380.00.

These are used in the large Stead drone Quadcopter shown above, clearly a top qualityprofessional and expensive product.

This is a very heavy lift and long endurance copter and is completely excessive andhazardous for most uses and needs.

This combination will work well for a Quadcopter with a total weight of up to 24

pounds and can achieve 30 to 40 minute flight times. This is a copter designed for very serious uses that demand its heavy lift and long

endurance capabilities and is not for amateurs. Disaster relief, search and rescue, fire

spotting, surveillance, ecological andgeographical survey and mapping areappropriate uses.

Professional Grade Power System for MediumQuadcopters (16 inch Propellers)

Clearly, applying similar quality to amore reasonably sized (and cost)
http://quadcoptersarefun.com/MulticopterDesign/TMotor70AmpESC.jpghttp://quadcoptersarefun.com/MulticopterDesign/TMotor29Prop.jpghttp://quadcoptersarefun.com/MulticopterDesign/TmotorU8Pro1.png


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copter is normally going to be a lot more practical. A380KV T-Motor 4008is $85.00, 16x5 CF Prop $90.00 a pair and 30 Amp Pro ESC

$50.00 @ four each = $720.00. This setup will work well for a copter up to 10 pounds or so and provide exceptional

durability, efficiency and endurance.

This is a very practical setup for a professional Quadcopter for photo or video usewith full sized cameras and brushless gimbals.

You can choose 4S 14.8 volt, 5S 18.8 volt or 6S 22.2 volt batteries and 14 to 17 inchprops according to your total weight.

With a proper setup you could reasonably expect to achieve practical 30 minute plusflight times with full camera equipment.

And a top quality 70 AMP ESC (speed controller) to go with it.

This is a very superior ($120.00)KDE 4014XF-380KV Motorwith 3 largereplaceable ABEC bearings rated at 200 hours. This motor is capable of using 13" to 18" propellers and operating efficiently with a

wide range of batteries from 3 cellcellsto 6 cellcells. This KDE Motor has a phenomenal range of operation and can be used on a 7 pound

to a 20 pound Quadcopter. Every component and manufacturing technique was clearly optimized to produce the

best possible motor without compromise. This motor has a finned heat-sink case and a self ventilated design with high

temperature encapsulated components. In fact it is designed to run, if necessary, continuously at temperatures that would

instantly destroy most other motors. It is reasonable to expect that various configurations could provide well over an hour

of useful operating time with cameras. It is feasible to produce a Quadcopters that will approach the performance of the

$15,000.00 Stead drone at a fraction of the cost. A similar practical lifting capability and nearly 40 minute useful flight times should

be achievable even with 18 inch Propellers. And given the extreme over design and ruggedness of the motors, similar reliability

and longevity could also be expected. This is the motor I will be using in my next Quadcopter and I will allow for up to 18

inch propellers.
http://www.rctigermotor.com/html/2013/Professional_0912/52.htmlhttp://www.rctigermotor.com/html/2013/Professional_0912/52.htmlhttp://www.rctigermotor.com/html/2013/Professional_0912/52.htmlhttp://www.kdedirect.com/KDE4014XF380.htmlhttp://www.kdedirect.com/KDE4014XF380.htmlhttp://www.kdedirect.com/KDE4014XF380.htmlhttp://quadcoptersarefun.com/MulticopterDesign/Tmotor16Prop.jpghttp://quadcoptersarefun.com/MulticopterDesign/TMotor4008.jpghttp://www.kdedirect.com/KDE4014XF380.htmlhttp://www.rctigermotor.com/html/2013/Professional_0912/52.html


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KDE has recently announced additional motors in a variety of sizes and these are thetop choice wherever possible.

A Hyper Efficient Medium Smaller Professional Grade Motor for Long Endurance

The $70.00T-Motor MN3508 380KV Navigator series motoris ideal for long flighttime applications.

This is the only motor in this size that can get G/W efficiencies over 17 at 50 percent

throttle. If you want to build a 4-8 pound copter for maximum endurance this is the motor to

use with a 4 cell Li-Po. Because of its extremely high efficiency in its hover range it is also a candidate for

high efficiency lithium batteries. Panasonic or LGs high power Lithium batteries have about twice the energy density

of the Li-Pos we normally use. But maximum discharge is only 2C so low current draw is required, the high

efficiency of these motors can provide that. Carbon fibre 14 inch to 16 inch propellers will be required.

Professional Grade Power System for Small Quadcopters (10 inch to 14 inch Propellers)

The largest market segment is for Quadcopters in frame sizes that use 10 to 14 inchpropellers and weigh 3 to 7 pounds.

The650 KV T-Motor MT3506at $65.00 is a high quality small, powerful pancakethat can turn 10 to 14 inch props.

With a 3 cell Li-Po battery and T-Motor 14 inch prop at $73.00 a pair it can lift up to7 pounds and achieve very good endurance.

Add 4 T-Motor 18 Amp ESCs at $27.00 @ four each = $514.00 for top qualitymotors, props and ESCs.

This small pancake motor can achieve good efficiency with 3S 11.1 volt or 4S 14.8volt Li-Po batteries and an appropriate sized prop.
http://www.rctigermotor.com/html/2013/Navigator_0910/36.htmlhttp://www.rctigermotor.com/html/2013/Navigator_0910/36.htmlhttp://www.rctigermotor.com/html/2013/Navigator_0910/36.htmlhttp://www.rctigermotor.com/html/2013/Professional_0912/49.htmlhttp://www.rctigermotor.com/html/2013/Professional_0912/49.htmlhttp://www.rctigermotor.com/html/2013/Professional_0912/49.htmlhttp://quadcoptersarefun.com/MulticopterDesign/TMotor14x48Props.jpghttp://quadcoptersarefun.com/MulticopterDesign/TMotorMN3508.jpghttp://quadcoptersarefun.com/MulticopterDesign/KDE4014XF-380.jpghttp://quadcoptersarefun.com/MulticopterDesign/KDE4014XF-380B.jpghttp://www.rctigermotor.com/html/2013/Professional_0912/49.htmlhttp://www.rctigermotor.com/html/2013/Navigator_0910/36.html


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The frame should be sized to accept up to 14 inch propellers and various batteryconfigurations.

It should be configurable to achieve 20+ minute flight times with a GoPro size cameraand brushless gimbal plus FPV or telemetry.

This would still be a very capable and rugged Quadcopter capable of professional

results and reliability.

The above Motor - Propeller - ESC setups are all as close to professional quality aswe can currently make them.

Consumer Grade Power System for Medium Quadcopters (14 inch to 16 inch Propellers)

It is also possible to build a reasonably reliable and efficient Quadcopter using lessexpensive components.

The $45.00SunnySky 390KV X4112S motoror the really low cost $18.00RCTimer5010-14 360KV motor.

Which will work well with an easy to install and low EMF $40.00Hobbywing four in

one ESC
http://www.himodel.com/electric/SUNNYSKY_X4112S_400KV_Outrunner_Brushless_Motor_for_Multi-rotor_Aircraft.htmlhttp://www.himodel.com/electric/SUNNYSKY_X4112S_400KV_Outrunner_Brushless_Motor_for_Multi-rotor_Aircraft.htmlhttp://www.himodel.com/electric/SUNNYSKY_X4112S_400KV_Outrunner_Brushless_Motor_for_Multi-rotor_Aircraft.htmlhttp://www.rctimer.com/product_575.htmlhttp://www.rctimer.com/product_575.htmlhttp://www.rctimer.com/product_575.htmlhttp://www.rctimer.com/product_575.htmlhttp://mymobilemms.com/OFFTHEGRIDWATER.CA/index.php?main_page=product_info&cPath=2_4&products_id=203http://mymobilemms.com/OFFTHEGRIDWATER.CA/index.php?main_page=product_info&cPath=2_4&products_id=203http://mymobilemms.com/OFFTHEGRIDWATER.CA/index.php?main_page=product_info&cPath=2_4&products_id=203http://mymobilemms.com/OFFTHEGRIDWATER.CA/index.php?main_page=product_info&cPath=2_4&products_id=203http://quadcoptersarefun.com/MulticopterDesign/Hobbywing4in1ESC.jpghttp://quadcoptersarefun.com/MulticopterDesign/RCTimer5010.jpghttp://quadcoptersarefun.com/MulticopterDesign/SunnySkyZ4112S.jpghttp://quadcoptersarefun.com/MulticopterDesign/TMotor14x48Props.jpghttp://quadcoptersarefun.com/MulticopterDesign/TMotorMT3506.jpghttp://mymobilemms.com/OFFTHEGRIDWATER.CA/index.php?main_page=product_info&cPath=2_4&products_id=203http://mymobilemms.com/OFFTHEGRIDWATER.CA/index.php?main_page=product_info&cPath=2_4&products_id=203http://www.rctimer.com/product_575.htmlhttp://www.rctimer.com/product_575.htmlhttp://www.rctimer.com/product_575.htmlhttp://www.himodel.com/electric/SUNNYSKY_X4112S_400KV_Outrunner_Brushless_Motor_for_Multi-rotor_Aircraft.html


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And they both work well with RC Timer 15x5.5 inch (4 for $28.00) or 16x5.5 inch (4for $35.00) CF propellers.

The Sunnysky Combo will cost about $260.00 and work very efficiently for coptersup to about ten pounds.

The RCTimer Combo will cost about $150.00 and will provide extended flight timefor copters up to about 6 pounds.

These motors will both actually support up to 17 inch propellers and work with 3 to 6cell LiPo batteries.

You could still design a copter that would get 30 minute flight times while carrying aGoPro and gimbal if desired.

The frame for either of these motors should be designed to support at least 16 inchprop diameter and 17 inch would be better.

These will not last as long nor be as reliable as the previous T-Motor configurations

but will still deliver lots of solid use.

Consumer Grade Power System for Small Quadcopters (8 to 12 inch Propellers)

Here is a durable and low cost alternative for powering smaller hobby or even semi-pro sub 5 pound Quadcopters.

The DJI 2212 Motors provided with their low cost ARF Flame wheel Quadcopters areunusually durable and cost $24.00 each.

And DJI specially hubbed 10 inch plastic props at $8.00 a pair are well balanced,efficient and rugged.

And this easy to use $40.00 four in one ESC eliminates a power distribution board,reduces EMF and provides good reliability.
http://quadcoptersarefun.com/MulticopterDesign/DJI10InchProp.jpghttp://quadcoptersarefun.com/MulticopterDesign/DJIMotor.jpghttp://quadcoptersarefun.com/MulticopterDesign/RCTimer16Props.jpghttp://quadcoptersarefun.com/MulticopterDesign/RCTimer15Props.jpg


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For $150.00 you can actually get quite a useful and durable power system for asmaller sub five pound quadcopter.

The $40.00 Sunny Sky X4108S pancake motor is also capable of being used onQuadcopters lifting up to 10 pounds.

It is well regarded, efficient and durable and is suitable for use with 14 or 15 inchpropellers and 4 cell to 6 cell Li-Po batteries.

Clearly these are not the only alternatives.o If you want to use your copter for constant, professional use you will want

something like the first 3 configurations.o For occasional, hobby or non-critical use for flying, FPV and / or personal

video or photography the others should be OK.o

The KDE and Pro T-Motors bearings last longer and are more weather proofand reliable than less expensive alternatives.o And the more expensive Carbon Fibre props are more efficient, better

balanced and more durable than cheaper alternatives.o But properly installed on an appropriate copter the less expensive alternatives

listed can provide many reliable hours of flying.o I have favoured slow speed pancake motors because efficiency and flight time

benefit from the larger propellers they can use. The above illustrates just some of the possibilities in identifying an appropriate power

system for your project.

The Quad-Copter Frame

There are many types of frames and it is most important to put together a frame that isappropriate for your use.

Multicopter frames are available as bare frame kits, Almost Ready To Fly or ReadyTo Fly copters.

Most professional grade Multicopters are made from fibre glass and carbon fibre cuttubing and plate.

o Carbon fibre is very strong, but is also brittle and can shatter on impact, it isalso hard to machine and to glue to.

o

Fibre glass weighs a bit more for equivalent strength but is more shatterresistant and easier to machine and glue to.
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o Fibre glass or carbon fibre tube and sheet construction are very suitable to usefor making your own copters.

Many consumer grade Multicopters are made with injection moulded plastic parts andaluminium tubing.

o Some injection moulded parts can be very durable (Iriss Zytel frame arms for

instance), but others are not and break easily.o Square aluminium tubing frame arms are common, but they tend to bend or

break with annoying frequency in normal mishaps.o Except in specialized welded H or box frames aluminium tubing frame arms

are sub optimal and will not be covered here. Some of the newer, smaller, commercially made Quadcopters have monolithic

injection moulded plastic shells.o On smaller copters shells can be quite durable but they would be too fragile on

larger ones even if mould costs were justified. A few Quadcopters have monolithic shells made from vacuum formed laminated

Kydex or other plastic sheeto

Vacuum formed shells of laminated Kydex have proven very durable on smallcopters and are very good for waterproof uses.

o At least one vacuum formed copter has been made with blade guards, the SafeFlight 4410 (unfortunately out of business).

Hand laid fibre glass or carbon fibre is also popular on high end quadcopters.o There are some very attractive, hard to get and not inexpensive hand laid fibre

glass and carbon fibre shells made by DeX.o There are also a variety of fibre glass shells for civilian, commercial and

military use including an amphibious one.o Fibreglass shells tend to be expensive and may get damaged in use and can be

difficult to repair.

Each type of construction has advantages and disadvantages, it is important to figureout what meets your needs.

Prop to prop and prop to frame clearance limit the max diameter of your propellerblades.

o Allowing for various prop diameters will let you tune the copter for its currentweight, batteries and function..

o Allow an additional half inch of clearance from prop tip to tip or to centerframe to avoid asymmetrical prop wash vibration.

o A major design criteria is to size the frame appropriately for the largestpropellers you might ever want to use.

o

Generally bigger propeller diameter equals better efficiency and an X framelayout normally permits the largest possible props.o The motor speed and power and frame strength have to be matched to the

propeller diameter and to total lifting capacity.o Pancake Low KV, Low RPM motors can turn bigger propellers efficiently.o It is possible to overlap prop tips if you have one above the other, but it does

affect efficiency and induces asymmetric vibration.o Big slow props can have adverse vibration, instability, gust compensation and

response rate issues also so that is a downside. The additional motors of Hex and Octo copters can permit single motor out recovery

and provide smooth flight for video.

o

They need to use smaller propellers because of motor to motor clearancewhich is less efficient resulting in shorter flight times.


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o There is also additional cost and weight of the frames and extra motors andpropellers.

o And, the overall increase in complexity also reduces reliability.o High quality extended service larger pancake motors and props are just

starting to become available.

o

We are likely to see a shift to large Quadcopters from Hexa copters and Octocopters even for professional and commercial uses.

X Frame or Dead Cat

Conventional Small X Frame Quadcopter
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Typical Dead Cat or H Frame Quadcopter

X Frame versus H or Dead Cat: Advantages and Disadvantages

The Original X frame and more recent H or Dead Cat frames each have good and bad points.

The original X frame design is a good all around choice.o It is a symmetrical design, motor propeller units are spaced the same distance

from each other and from the center of the copter.o The weight (or mass) is also concentrated in the center of the copter.o This symmetry means all motor propeller units can be treated as equals and

control forces distributed equally.o For photo, video or FPV use, the camera(s) must be placed under the copter in

order to have visual clearance of the popellers.o This lowers the center of mass increasing forces required for pitching and

rolling the copter reducing performance somewhat.o It also requires an extended landing gear (which must also not visually

interfere with the camera) to clear the camera / gimbal.o With a camera the X frame also presents a taller profile which is affected more

by wind and gusts. The H or Dead Cat frame is specifically designed for photo / video applications and

permits a front mounted camera.o H design implies a central frame member interconnecting front and back

members that mount the prop/motor units on each end.o Originally H might have had a single central tube and could be subject to

twist, but for our examples we assume a rigid frame.

o

Dead Cat is named for a German enthusiast who turned his stuffed pet cat intoa quadcopter.
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o Dead Cat infers that clearance between front and back props will be largerthan side to side clearance.

o Since the camera is in line with the frame, it presents a minimal side profileand is less affected by wind and gusts.

o On an H or Dead Cat a short landing gear is normally used and mechanical

complexity and weight is somewhat reduced.o The mass is still centered and is narrow side to side but long front to back with

the battery counter balancing the forward camera.o This long, thin mass means that more force is required for pitch control than

for roll control.o Prop/motor units are close together on the sides but wider apart in the front

and back to clear the frame and the cameras view.o This also means more force is necessary to change pitch than is required for

roll.o The combination of these two effects definitely requires that pitch be given

more "authority" than roll.o

On an APM or Pixhawk, this means that the "Rate" Pitch PID P value needs tobe higher than the "Rate" Roll PID P value.

o Normally APM parameters assume Rate for Pitch and Roll are the same, sothey need to be unlocked and set separately.

For a small to medium quadcopter with a small camera and brushless gimbal an H orDead Cat is a more efficient design.

o An H or Dead Cat also generally has higher performance than an equivalent Xframe with an under mounted camera.

o For larger cameras, and just due to wide spread availability, the conventionalX frame is also a perfectly good option.

o Both frame designs provide an adequate camera platform, but where feasible,the H or Dead Cat can be superior.

The Carbon Fibre or Fibreglass Tube and Plate Frame

The carbon fibre or fibreglass tube and plate frame is popular because it is strong and

light and easily manufactured.

The Tarot 650 is a typical layout medium sized carbon fibre Quadcopter frame thatcan work with up to 17 inch propellers.

It features folding arms and landing gear.

Its ability to support pancake motors and 17 inch props means it can provide longflight times. Some people have said the quality of construction is not as good as it could be but for

$125.00 it is an amazing bargain.


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Fabrication requirements and techniques for fibreglass and carbon fibre tube and platecopters.

On the copters shown above the method of attachment is by clamping carbon fibre

tube frame arms with aluminum brackets. This is because of the difficulties in attaching carbon fibre parts as well as the stress

that can result from drilling the tubing. Fibreglass is not quite as strong or light as carbon fibre but it is more flexible and

easier to join and machine. If what you need is available in a commercial frame kit you are normally better off

buying it as you will spend more making your own. It will also take a lot of time and effort to design the copter, to obtain the components

and to, cut, drill, machine and fabricate them. There is also a strong possibility that design and fabrication mistakes and

misperceptions will require that some things get redone.

If you have sufficient reason to make your own frame, tube and plate construction isoften most practical for home production.

It is reasonable to mix materials, commonly carbon fibre frame tubes and fibreglasscentral and motor mounting plates.

Carbon fibre and fibreglass tubing and plate can be cut with a hacksaw or power jig orband saw (with metal or fibreglass blades).

It can also be drilled and milled with HSS or TC coated drills and mills, but all toolingwears out very quickly cutting these materials.

Carbon fibre in particular is tricky to cut, drill and machine, it can tear, shatter or de-laminate if not done smoothly and slowly.

A drill press is mandatory for carbon fibre, you cant center punch a pilot drill hole, soit needs to be held precisely in place.
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Avoid milling of carbon fibre if at all possible, it is very difficult to accomplishsatisfactory results.

You will see carbon fibre plates that have milled slots on consumer copters but thesehave generally been cut with a water jet.

With carbon fibre you will generally get better results drilling precision placed holes

rather than attempting to mill slots in it. You can carefully and slowly cut a carbon fibre plates exterior edges with a power

saw and smooth them with a Dremel tool. If you must put in slots consider drilling a hole at each end and using a small circular

saw on a Dremel or flex shaft to connect them. It will be necessary to provide appropriate brackets to clamp the motor mounts and

central hub to the frame arm tubes. Tubing needs to be clamped but must not be crushed, silicone or rubber gasket can

provide protection and vibration isolation. Hardware should be aluminum or stainless steel machine screws and you can use

Nylok nuts or Blue Loctite on regular nuts.

Plate separation and mounting can be provided with Nylon or aluminum standoffs. (Note: It would be nice if somebody made an X internal slip-glue fit ferrule for the

center of the frame tubes but they dont - yet!) There are a wide variety of Carbon fibre and epoxy fibreglass components to choose

from. Carbon fibre products are available fromRockWest CompositesandCarbon Fibre

Tube ShopandDragon Plate A really good article on cutting and gluing carbon fibre products fromCarbon Fibre

Tube Shop Fibreglass and Carbon Fibre products are available from:CST SalesandACP Sales A datasheet for3M 2216 Epoxy Glueand a source for itAmazonI use this myself

and it is great! A datasheet forLoctite 9430 Glueand a source for Loctite 9340Amazon

Using manufactured Plastic and Fibreglass Components in Your Own Frames.

Although often not reasonable to make yourself some parts can be used effectively inyour own designs.

There are retrofit kits like the Team Black-sheep FPV sub-frame for a DJI Flamewheel quadcopter that reuse its plastic frame arms.

And there are many cases where components from various frames can be used to good

effect in our own designs. It is necessary to research your individual design to assure that the component pieces

are actually available from the distributors. Research can provide an excellent source of very desirable components: Like $14.00 CNC milled ultra toughfibreglass frame armsused in Hover things

Quadcopters: (Their FPV Pro is a great frame).
http://www.rockwestcomposites.com/http://www.rockwestcomposites.com/http://www.rockwestcomposites.com/http://www.carbonfibertubeshop.com/http://www.carbonfibertubeshop.com/http://www.carbonfibertubeshop.com/http://www.carbonfibertubeshop.com/http://www.dragonplate.com/http://www.dragonplate.com/http://www.dragonplate.com/http://www.carbonfibertubeshop.com/cut%20&%20bond.htmlhttp://www.carbonfibertubeshop.com/cut%20&%20bond.htmlhttp://www.carbonfibertubeshop.com/cut%20&%20bond.htmlhttp://www.carbonfibertubeshop.com/cut%20&%20bond.htmlhttp://www.cstsales.com/products.htmlhttp://www.cstsales.com/products.htmlhttp://www.cstsales.com/products.htmlhttp://www.acpsales.com/Carbon-Fiber.htmlhttp://www.acpsales.com/Carbon-Fiber.htmlhttp://www.acpsales.com/Carbon-Fiber.htmlhttp://multimedia.3m.com/mws/mediawebserver?6666660Zjcf6lVs6EVs666GGfCOrrrrQ-http://multimedia.3m.com/mws/mediawebserver?6666660Zjcf6lVs6EVs666GGfCOrrrrQ-http://multimedia.3m.com/mws/mediawebserver?6666660Zjcf6lVs6EVs666GGfCOrrrrQ-http://www.amazon.com/3M-Scotch-Weld-Epoxy-Adhesive-EC-2216/dp/B000WXL090/ref=sr_1_2?ie=UTF8&qid=1392508104&sr=8-2&keywords=3m+2216http://www.amazon.com/3M-Scotch-Weld-Epoxy-Adhesive-EC-2216/dp/B000WXL090/ref=sr_1_2?ie=UTF8&qid=1392508104&sr=8-2&keywords=3m+2216http://www.amazon.com/3M-Scotch-Weld-Epoxy-Adhesive-EC-2216/dp/B000WXL090/ref=sr_1_2?ie=UTF8&qid=1392508104&sr=8-2&keywords=3m+2216http://tds.loctite.com/tds5/docs/HYSA9430-EN.pdfhttp://tds.loctite.com/tds5/docs/HYSA9430-EN.pdfhttp://tds.loctite.com/tds5/docs/HYSA9430-EN.pdfhttp://www.amazon.com/Loctite-9340%C3%A2-Hysol-Adhesive-Temperature/dp/B000WXL1YE/ref=sr_1_1?s=industrial&ie=UTF8&qid=1392508821&sr=1-1&keywords=loctite+9340http://www.amazon.com/Loctite-9340%C3%A2-Hysol-Adhesive-Temperature/dp/B000WXL1YE/ref=sr_1_1?s=industrial&ie=UTF8&qid=1392508821&sr=1-1&keywords=loctite+9340http://www.amazon.com/Loctite-9340%C3%A2-Hysol-Adhesive-Temperature/dp/B000WXL1YE/ref=sr_1_1?s=industrial&ie=UTF8&qid=1392508821&sr=1-1&keywords=loctite+9340http://www.hoverthings.com/fliparmblack.htmlhttp://www.hoverthings.com/fliparmblack.htmlhttp://www.hoverthings.com/fliparmblack.htmlhttp://www.hoverthings.com/fliparmblack.htmlhttp://www.amazon.com/Loctite-9340%C3%A2-Hysol-Adhesive-Temperature/dp/B000WXL1YE/ref=sr_1_1?s=industrial&ie=UTF8&qid=1392508821&sr=1-1&keywords=loctite+9340http://tds.loctite.com/tds5/docs/HYSA9430-EN.pdfhttp://www.amazon.com/3M-Scotch-Weld-Epoxy-Adhesive-EC-2216/dp/B000WXL090/ref=sr_1_2?ie=UTF8&qid=1392508104&sr=8-2&keywords=3m+2216http://multimedia.3m.com/mws/mediawebserver?6666660Zjcf6lVs6EVs666GGfCOrrrrQ-http://www.acpsales.com/Carbon-Fiber.htmlhttp://www.cstsales.com/products.htmlhttp://www.carbonfibertubeshop.com/cut%20&%20bond.htmlhttp://www.carbonfibertubeshop.com/cut%20&%20bond.htmlhttp://www.dragonplate.com/http://www.carbonfibertubeshop.com/http://www.carbonfibertubeshop.com/http://www.rockwestcomposites.com/


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DJI injection moulded frame arms from their Flame wheel copters are used in theTBS Discovery FPV frame.

And although this injection molded 3DR Iris arm isnt cheap at $27.00 it is made ofultra strong and resilient Zytel.

Homemade waterproof frame using a hinged electrical box

An excellent, very clean, rugged and waterproof design using carbon fibre arms and plastic

electrical and plumbing parts.
http://quadcoptersarefun.com/MulticopterDesign/IrisArmBlue.jpghttp://quadcoptersarefun.com/MulticopterDesign/TBS-Discovery-1.jpghttp://quadcoptersarefun.com/MulticopterDesign/HoverthingsFlipArm.jpghttp://quadcoptersarefun.com/MulticopterDesign/HoverthingsFlipFPV.jpg


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Here is a link toAlec Shorts construction article in Makezine I like the use of the central 4 way hub for stabilizing the tubes and the slip fit

adjustable tension Ts for motor mounts are also great. The mounting of an APM or Pixhawk would really require the separate GPS /

Magnetometer module in order to work correctly. There are a wide variety of latch type weatherproof electrical boxes which could be

used for this.

The main requirement is to get CF tube with an outer diameter appropriate to theplumbing / electrical fittings you want to use.

Ill definitely be visiting the electrical and plumbing section the next time Im inHome Depot.

Vacuum Formed Frames and Components.

Although this is specialized and requires a vacuum forming press it may be justifiedfor some applications.

A vacuum molding press can be made relatively inexpensively that can make wholesmall shell type frames or for components.

Copters made this way can be made weather tight and even water proof and they canbe incredibly tough.

Kydex is a laminated plastic sheet that produces a quite strong monocoque shell whenmolded properly.

The no longer in production Safe Flight Copters SFC4410-1 has a vacuum formedpropeller protected H Quad Frame.
http://makezine.com/projects/wavecopter-a-waterproof-quadcopter/http://makezine.com/projects/wavecopter-a-waterproof-quadcopter/http://makezine.com/projects/wavecopter-a-waterproof-quadcopter/http://quadcoptersarefun.com/MulticopterDesign/wavecopter.jpghttp://makezine.com/projects/wavecopter-a-waterproof-quadcopter/


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And the inexpensive ($120.00) and extra tough, water proofAquacopter frame(Areally excellent tough frame).
http://www.aquacopters.com/http://www.aquacopters.com/http://www.aquacopters.com/http://quadcoptersarefun.com/MulticopterDesign/Aquacopter.jpghttp://quadcoptersarefun.com/MulticopterDesign/SFC4410.pnghttp://www.aquacopters.com/


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A fully functional vacuum forming system can actually be constructed with a shopvacuum and an electric grill.

Vacuum forming can also be used to make central shells for copters with tube, plasticor fibre glass frame arms.

This may be over specialized for most uses, but if you want to make tough, lightcentral frame shells or covers.

Or, if you want to build multiple small to medium Quadcopters that are tough andwaterproof this could be just the ticket.

(Or you could just buy an Aquacopter frame!!!)

Specific Building Examples and Techinques

Some design considerations for a medium large, high efficiency, heavy liftQuadcopter build.

o A simple, rugged and very versatile X Quadcopter with a frame sized largeenough to accept 18 inch propellers might include:

o High quality 20mm carbon fibre tube frame arms with SteadiDrone motormounts and frame tube clamps from EBay or China.

o Cut and drilled carbon fibre or fibreglass top and bottom central frame platesmounted to the tube clamps and standoffs.

o A custom or commercial off the shelf landing gear system.o A Pro configuration might include top rated $120.00 KDE 4014XF-380KF

motors and a 30 amp 3 - 6 cell four in one ESC.
http://quadcoptersarefun.com/MulticopterDesign/VacuumPress.gif


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o The motors and ESC would cost about $540.00 and you would get a coptertuneable to lift up to 20+ pounds in total weight.

o It is reasonable to get this configuration to achieve usable 60 minute flighttimes even with photo or video equipment aboard.

o A more conservative hobby configuration might include $40.00 SunnySky

X4108S 380KV motors and a 25 amp four in one ESC.o The motors and ESC would cost about $200.00 and you would get a copter

tuneable to lift up to 10+ pounds in total weight.o Even with this setup you could achieve usable flight times in excess of 30

minutes with small to medium consumer size cameras. Some additional features that need to be considered are:

o A third frame plate under the two frame tube sandwiching plates canaccommodate the batteries, ESCs and Receiver.

o A vacuum formed, fabricated or adapted top and bottom shell canweatherproof the copter and increase its survivability.

o This frame is less than 27 inches from corner to corner, but props can be

removed for transport or folding arms could be used.o This frame will be very light and strong and it will allow lots of latitude in

how it is set up and it will be easy to upgrade.o Its ability to accept larger props even with an inexpensive power system will

provide much better than average flight times.o The copters capabilities will be according to the power system selected, the

battery combination used and the total weight.o You can include a camera gimbal under the center plate, make sure the landing

gear does not interfere with the cameras view.o The landing gear should minimize interference with prop wash and provide

strong, resilient and stable support.o

If you really are determined to build your own frame, this (or a smaller lighterversion of it) is a good place to start.


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The above design is a capable pro-grade Quadcopter with an exceptionally wideperformance and endurance envelope.

A Small Quadcopter Optimised to Use High Efficiency Lithium Batteries

Modern ultra efficient Lithium batteries can have nearly twice the energy per unitweight of the LiPo batteries we normally use.

3300 mah 3.7volt Panasonic NCR18650B batteries weigh 47 grams versus a normal

LiPo equivalent of about 100 grams per cell. Their disadvantage is that their maximum discharge rate is only 2C so 6.6 Amps. They will also last for many times the number of charge discharge cycles of our

normal LiPos. Used properly a copter using these batteries can get nearly twice the flight time of one

with the same weight of LiPo batteries. The most important factor in designing a copter to use these batteries is to keep the

weight low enough that their is sufficient current. This quadcopter design uses T-Motor MT2206 1200 KV 30 gram motors and 10 inch

props with a light carbon fibre frame. It includes a 2S 2P 6600mah lithium battery, flight controller, receiver and even an

FPV camera and transmitter.
http://quadcoptersarefun.com/MulticopterDesign/Quad18X12.jpg


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It weighs about a pound and since the battery is 2 parallel it can provide 13.2 amps ofcurrent (max current is less than 10 amps.)

Xcalc computationsshow that a hover time of 60 minutes might be possible with arealistic fly around time of over 40 minutes.

This is an easy to build practical and rugged design with exceptional capabilities and doublethe normal flight time.

A small practical Dead Cat H Frame for FPV and GoPro with Brushless Gimbal

This is a frame designed to be as small and light as possible for carrying a GoPro witha Brushless Gimbal and FPV.

The Dead Cat design has proven to be very efficient and does not require a downwardprotruding camera gimbal.

Depending on the battery this copter can weigh less than 2 pounds with cameras and abrushless gimbal.

You gain considerable agility and safety using as small a copter as possible. This frame also presents minimal side profile so is less affected by winds and gusts. In the future, harsher regulations for heavier UAVs will probably force migration to

small optimal multicopters like this one.
http://copter.ardupilot.com/wiki/advanced-multicopter-design/www.ecalc.ch/xcoptercalc.php?ecalchttp://copter.ardupilot.com/wiki/advanced-multicopter-design/www.ecalc.ch/xcoptercalc.php?ecalchttp://quadcoptersarefun.com/MulticopterDesign/Quad10X1.jpghttp://copter.ardupilot.com/wiki/advanced-multicopter-design/www.ecalc.ch/xcoptercalc.php?ecalc


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Ecalc calculations show realistic times for expected hover, but mix times for normal flightwould be much longer.

ECalc calulates mix as 50% hover to 50% max throttle use and with this efficient copter youwould never get close to that.

Normal flight times could be expected to be over 15 minutes with the setup shown.

Links To Specific MultiCopter Builds

Here is a link to Forrest Franzs build of a very simple, very light weight, very strongcarbon fibre Quadcopter frame
http://diydrones.com/forum/topics/build-your-own-copter-part-iii?xg_source=activityhttp://diydrones.com/forum/topics/build-your-own-copter-part-iii?xg_source=activityhttp://quadcoptersarefun.com/MulticopterDesign/QuadCompactH11FPV.jpghttp://diydrones.com/forum/topics/build-your-own-copter-part-iii?xg_source=activity


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And some links to some of Forrests extremely ambitious copter building techniquesand concepts.

o building-copters-with-round-tubes-stronger-lighter-easiero build-your-own-copter-part-iio build-your-own-copter-part-iiio build-your-own-copter-part-iv

A link to Stuart Dodins really niceX8 heavy lifter Octocopter
http://diydrones.com/group/arducopterusergroup/forum/topics/building-copters-with-round-tubes-stronger-lighter-easier-tohttp://diydrones.com/group/arducopterusergroup/forum/topics/building-copters-with-round-tubes-stronger-lighter-easier-tohttp://diydrones.com/forum/topics/build-your-own-copter-part-iihttp://diydrones.com/forum/topics/build-your-own-copter-part-iihttp://diydrones.com/forum/topics/build-your-own-copter-part-iiihttp://diydrones.com/forum/topics/build-your-own-copter-part-iiihttp://diydrones.com/forum/topics/build-your-own-copter-part-ivhttp://diydrones.com/forum/topics/build-your-own-copter-part-ivhttp://diydrones.com/profiles/blogs/project-custom-design-heavy-lift-x8-carbon-fiber-octocopterhttp://diydrones.com/profiles/blogs/project-custom-design-heavy-lift-x8-carbon-fiber-octocopterhttp://diydrones.com/profiles/blogs/project-custom-design-heavy-lift-x8-carbon-fiber-octocopterhttp://quadcoptersarefun.com/MulticopterDesign/ForrestsQuad.jpghttp://diydrones.com/profiles/blogs/project-custom-design-heavy-lift-x8-carbon-fiber-octocopterhttp://diydrones.com/forum/topics/build-your-own-copter-part-ivhttp://diydrones.com/forum/topics/build-your-own-copter-part-iiihttp://diydrones.com/forum/topics/build-your-own-copter-part-iihttp://diydrones.com/group/arducopterusergroup/forum/topics/building-copters-with-round-tubes-stronger-lighter-easier-to


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A Commercial MultiCopter Exhibiting Advanced Design Concepts

The Aeryon SkyRanger is an innovative and professional quality QuadCopter design for highend UAV applications.

This copter has a lot of things right and is really a study in good design and qualityconstruction.
http://quadcoptersarefun.com/MulticopterDesign/AeryonSkyRanger2.jpghttp://quadcoptersarefun.com/MulticopterDesign/StuartDodinX8.jpg


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1.

The rotating ball full enclosure camera Gimbal provides good weather protection andimproved performance.

2.

The motors are on the bottom under the arms.1. More aerodynamically efficient with no prop wash interference and very little

intake interference.

2.

Noticeably increased flight times, greater lift capability and quieter as well.3. High torque, low KV pancake style motors and slow turning, large diameter, high

efficiency props.1. This is much more efficient than faster motors with smaller diameter

conventional design props.2. This also increases flight times and load capacity and reduces the sound

footprint.4. Tapered carbon fibre frame arms are more aerodynamically efficient and are light and

very strong.5. The fully enclosed weather tight framework with snap latch type access makes

maintaining the copter easy.

6.

A simple spring loaded landing gear provides for uneven landing sites and minimalinterference with the prop wash.

This QuadCopter incorporates several excellent design concepts and shows what can be done

without budget constraints.

The Skyranger has features we can use in our own designs but it is important to understandall designs are compromises.

The 3DRobotics Iris is one of the best designed QuadCopters that you can actually get and itis a real bargain.

Conclusion and Additional Design Considerations

I have not covered either 3D printing or CNC machining.

o

These are both perfectly valid techniques for either whole frames or for partsor accessories.
http://quadcoptersarefun.com/MulticopterDesign/Skyranger.jpg


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o But most people do not have the equipment or capability which is why theyare not covered here.

o Clearly if you have either of these capabilities they can greatly enhance yourcopter projects.

I have also not covered in depth hand laid fibreglass or carbon fibre or vacuum

bagging.o You can make Dynamite frames or shells this way but it requires serious

individual skill and capability (especially carbon fibre). I have also not gone into detail about the engineering criteria for multicopters:

o A. I dont know.o B. From what Ive seen very few people do.o C. One who does is Paul Pounds PHD and here is his Paper on the subject:

Quadrotors If you stick to a simple design and try to keep frame arm to a simple single small tube

under the prop wash it will work fine.o Round tubing has about half the flat plate area (prop wash interference) as the

same sized square tubing.o You can improve efficiency by putting the motor prop under the frame arm

but then there are frame design and clearance issues. Try to keep the weight centralized as much as possible and keep the flight controller

near the horizontal centercentreif possible.o So that the copter tends to roll and pitch as though pivoting around the center

of mass and around the flight controller.o But it is not as critical as some people have made it out to be because the

stabilizing throttles will automatically compensate. You can do a lot with a rudimentary understanding of the forces involved, if you need

more it is a career, not a hobby.

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