Hi,
I'm considering starting a project building a F550. I'm a complete n00b at this aka absolute beginner. Since everything is new to me I've written up everything I learned so far including references and I'm currently at the point that I could use some feedback. I hope this is not too overwhelming as I had to dig up everything from scratch and go from there.
I've also been reading the 'read me first' and happy to have discovered aerosim which can give me some virtual practice.
The eventual ambition I have is to mount a gopro and het about 15 min. flight time. Getting there I've stumbled on some gaps and assumption to which I certainly could use some feedback.
During the writing of this I encountered a couple of questions I've marked these in red and would be most grateful if someone can shed some light on them!
Here's what I got so far (most of it is based on this)
_____________________________________GENERAL KNOWLEDGE_____________________________
Acronyms and Terms explained
Craft related
Y-4 Quadcopter (4 propellers)
Y-6 Hexacopter (6 propellers)
Y-8 Octacopter (etc.)
AUW All up weight (total weight of craft)(RoT: Thrust = 2x AUW)
The amount of propellers have the following impact: more propellers means more stable, and potentially: longer flight & more carrying capacity. Additionally when one motor fails: Y-4 will crash, Y-6 can get safely to ground (no control over direction), Y-8 can get safely home (full control remains)
Other
FPV First Person View
AP Aerial Phography
RoT Rule of Thumb
HK Hobbyking
RPM Revolutions per minute
Movement(rotation in one degree)
Pitch Nose up/down
Yaw Nose left/right
Roll Wings up/down
Control (Based on ‘normal’ airplane)
Elevation Controls the pitch (Horizontal flap on tail)
Ailerons Controls the roll (flaps on wings)
Rudder Controls the yaw (Vertical flap on tail)
Thrust Amount of power the propellers give
Thrust vs Elevation: when elevation is increased the nose of the plane goes up, this means that the original lift force vector is split up into two orthogonal force vectors which again means that the lift force vector becomes smaller = the plane starts to drop. By increasing thrust the elevation can be maintained (or increased).
______________________ CHOOSING PARTS AND SOME BASICS___________________________
Frame
Arm e.g. Y-6 has 6 arms
Centre plate holds the arms and the FC
Landing gear usually in combination with:
Gimbal a device where you attach your e.g. Camera to. The gimbal rotates in 2 or 3 Degr. of freedom to keep you camera stable.
Suggested
Frame: Flame Wheel F550 (Y-6)
http://www.hobbyking.com/hobbyking/store/uh_viewitem.asp?idproduct=49726
(435g)
()
Landing gear and Gimbal: Gopro brushless gimbal:
http://www.quadframe.us/collections/camera-mounts/products/gopro-brushless-gimbal
(190 g.)
And to be complete in weight: gopro silver ed.: (74g.)
()
FC
Flight Controller (Some ex.: KK, MultiWii, Ardupilot, Naza, Naze, Rabbit, WKM ). This is where the sensors are/go (gyro, accelerometer, sonar, GPS, Magnetometer, Barometer)
Gyro Detects rotation in all 3 degrees but will orientation will ‘drift’, hence ideal in combination with a:
Magnetometer aka compass Helps the gyro to keep its bearing.
GPS Global Positioning System, uses satellites to calculate exact (2-5m) position
Sonar Detects distance to ground (low altitude <15m) hence ideal in combination with:
Barometer Detects altitude of place (high altitude)
The least you need on board is a Gyro. Sensors can be bought separate or integrated.
Suggested FC: HK FC v1, 2.1 or 3
http://www.hobbyking.com/hobbyking/...ti_Rotor_Control_Board_V2_1_Atmega168PA_.html
(14.5g)
()
Motor
That which drives the propeller. Specifications:
Max current(A) This is closely related to the ESC (see below)
Shaft dia diameter of the shaft to which the propeller adapter will be attached
Suggested prop ‘ideal’ prop for this motor
Thrust (based on suggested prop)
Weight grams
Lipo(3S-4S) Lithium Polymer Battery (light weight high energy density)
kV RPM/V
RoT: the lower the voltage input the bigger the propellers that can be attached, the more thrust you can gain (per revolution)
Motor Mount That which attaches the motor to the frame (quite important).
Motor kV = RPM / Battery V or RPM = Motor kV x Battery V
E.g. 3S battery with a 600kV motor: RPM = 600 x 11.1 = 6660 RPM (without load)
This will start to make sense as soon as wel reach the propellers.
Another well known formula:
W(watt/power) = V(voltage) x I(ampere)
Suggested motors: 600kV or lower
http://www.hobbyking.com/hobbyking/...y_4206_530kv_Brushless_Multi_Rotor_Motor.html
(68g x 6 = 408g)
( x 7 = 147)
propeller adapter
is attached to the motor and the propellers are attached to it. Included with motor.
Propeller
The blades that make the craft fly. Specifications:
Diameter the length of the entire blade or the virtual circle the propeller generates.
Pitch amount of travel per revolution (inch per revolution) (RoT, low pitch = less vibrations and more overall stable)
When you mount 10 inch diameter prop RPM (originally 6660) of motor will be reduced to 3600 RPM (Revolutions Per Minute). WHY?
60 Revolutions Per Second.
With a pitch of e.g. 3.8 you get 3.8 inch per revolution: so 60x3.8 inch/second = 228 Inch/Sec = 5.7 m/sec
With a pitch of e.g. 6 inch you get 60 x 6 = 360 Inch/Sec = 9.1 m/sec
Suggested propeller:
To prevent unwanted YAW you want the opposite arms to have one CW and one CCW propeller so they rotate in opposite directions. The frame is 550mm which theoretically means that the max propeller radius can be 11 inch but the motors will likely not be on the edge so its safer to keep the manufacturer suggested 8~10 inch.
10x4.5 SF Props Black CW (2pc) CCW (2pc)
http://www.hobbyking.com/hobbyking/store/__25824__10x4_5_SF_Props_Black_CW_2pc_CCW_2pc_.html
(60g. for the four)
So in total (60*1.5 = 90g)
($ 3 x 2 = 6)
Its completely unclear whether the propellers will fit around the shaft of the motors. How do I figure that out?
ESC
Electronic Speed Controller
ESC supplies power from battery but not constant, it varies according to input signal.
ESC also has BEC (Battery Eliminated Circuit). BEC is nothing but 5V output from ESC that can power up receiver, servomotor(for camera gimbal) and FC.
RoTs:
- the Ampere rating of the ESC should be higher than max amp rating of motor (about 1.2 to 1.5 higher).
- It should be programmable
- Go for quality (check user reviews)
The above motors suggests 25 Amp ESC’s while it’s a max 25 A motor, which contradicts this. WHY? I’m aware that things can burn through when to much current is drawn through them so I’ll go with a higher ESC.
Suggested ESC: HobbyKing 30A BlueSeries Brushless Speed Controller
I’m REALLY in the dark here so I just went for the first link I encountered and checked the RoT: http://www.hobbyking.com/hobbyking/...0A_BlueSeries_Brushless_Speed_Controller.html
(28g x 6 = 168g)
( x 7 = 84)
Battery
The fuel for the engine. Specifications:
mAh milli Ampere hours. In short the total amount of energy
C discharge rating. How fast you can discharge the battery
S S stands for the amount of cells in series (which means that the voltage output of each cell is added to the total V.). One cell has an output of 3.7V, hence a 3S outputs 11.1 V and a 4S outputs 14.8.
P Cells can also be put in parallel which increases the current.
Suggested Battery
Well… assuming the motors are correct they draw: 6x25A = 150 A at max thrust. So that’s A LOT (potential overkill ?). Again no clue, so trial and error, lets go for 4S (checked motor and ESC they both can handle it). ZIPPY Compact 4000mAh 4S 25C Lipo Pack has a discharge rate of 25C. So that’s a max of 25 x 4A (4000mA = 4A) = 100 A. We need 150 at least, so that’s not enough.
ZIPPY Flightmax 8000mAh 4S1P 30C makes 8*30 = 240A which is enough but weighs a whooping (845 g.)
()
Transmitter receiver
Suggestion taken from here: Turnigy 9X
http://blog.oscarliang.net/choose-rc-transmitter-quadcopter/
mode 2 is suggested to be the most common for Y-4, so I guess that accounts for Y-6 as well.
Hence:
http://www.hobbyking.com/hobbyking/..._Module_8ch_Receiver_Mode_2_v2_Firmware_.html
(19 g) (receiver module)
()
_____________________CONCLUSION SO FAR_______________________________
Now how do I calculate whether the craft can fly? Taking into account the weight:
<tbody>
</tbody>
2343.5 (or 2.4kg). This means I need at least a thrust of 5kg.
Total costs: 523 $ (378 EUR) Leaving out the gopro but taking spare parts into account.
I've got a *feeling* that the motors are too heavy. I've tried using eCalc but that completely eludes me. From what I gathered these motors are optimized for 12" props so I guess something lower is required. On the other hand, I *do* require quite a bit of lift.
pls shoot!
I'm considering starting a project building a F550. I'm a complete n00b at this aka absolute beginner. Since everything is new to me I've written up everything I learned so far including references and I'm currently at the point that I could use some feedback. I hope this is not too overwhelming as I had to dig up everything from scratch and go from there.
I've also been reading the 'read me first' and happy to have discovered aerosim which can give me some virtual practice.
The eventual ambition I have is to mount a gopro and het about 15 min. flight time. Getting there I've stumbled on some gaps and assumption to which I certainly could use some feedback.
During the writing of this I encountered a couple of questions I've marked these in red and would be most grateful if someone can shed some light on them!
Here's what I got so far (most of it is based on this)
_____________________________________GENERAL KNOWLEDGE_____________________________
Acronyms and Terms explained
Craft related
Y-4 Quadcopter (4 propellers)
Y-6 Hexacopter (6 propellers)
Y-8 Octacopter (etc.)
AUW All up weight (total weight of craft)(RoT: Thrust = 2x AUW)
The amount of propellers have the following impact: more propellers means more stable, and potentially: longer flight & more carrying capacity. Additionally when one motor fails: Y-4 will crash, Y-6 can get safely to ground (no control over direction), Y-8 can get safely home (full control remains)
Other
FPV First Person View
AP Aerial Phography
RoT Rule of Thumb
HK Hobbyking
RPM Revolutions per minute
Movement(rotation in one degree)
Pitch Nose up/down
Yaw Nose left/right
Roll Wings up/down
Control (Based on ‘normal’ airplane)
Elevation Controls the pitch (Horizontal flap on tail)
Ailerons Controls the roll (flaps on wings)
Rudder Controls the yaw (Vertical flap on tail)
Thrust Amount of power the propellers give
Thrust vs Elevation: when elevation is increased the nose of the plane goes up, this means that the original lift force vector is split up into two orthogonal force vectors which again means that the lift force vector becomes smaller = the plane starts to drop. By increasing thrust the elevation can be maintained (or increased).
______________________ CHOOSING PARTS AND SOME BASICS___________________________
Frame
Arm e.g. Y-6 has 6 arms
Centre plate holds the arms and the FC
Landing gear usually in combination with:
Gimbal a device where you attach your e.g. Camera to. The gimbal rotates in 2 or 3 Degr. of freedom to keep you camera stable.
Suggested
Frame: Flame Wheel F550 (Y-6)
http://www.hobbyking.com/hobbyking/store/uh_viewitem.asp?idproduct=49726
(435g)
()
Landing gear and Gimbal: Gopro brushless gimbal:
http://www.quadframe.us/collections/camera-mounts/products/gopro-brushless-gimbal
(190 g.)
And to be complete in weight: gopro silver ed.: (74g.)
()
FC
Flight Controller (Some ex.: KK, MultiWii, Ardupilot, Naza, Naze, Rabbit, WKM ). This is where the sensors are/go (gyro, accelerometer, sonar, GPS, Magnetometer, Barometer)
Gyro Detects rotation in all 3 degrees but will orientation will ‘drift’, hence ideal in combination with a:
Magnetometer aka compass Helps the gyro to keep its bearing.
GPS Global Positioning System, uses satellites to calculate exact (2-5m) position
Sonar Detects distance to ground (low altitude <15m) hence ideal in combination with:
Barometer Detects altitude of place (high altitude)
The least you need on board is a Gyro. Sensors can be bought separate or integrated.
Suggested FC: HK FC v1, 2.1 or 3
http://www.hobbyking.com/hobbyking/...ti_Rotor_Control_Board_V2_1_Atmega168PA_.html
(14.5g)
()
Motor
That which drives the propeller. Specifications:
Max current(A) This is closely related to the ESC (see below)
Shaft dia diameter of the shaft to which the propeller adapter will be attached
Suggested prop ‘ideal’ prop for this motor
Thrust (based on suggested prop)
Weight grams
Lipo(3S-4S) Lithium Polymer Battery (light weight high energy density)
kV RPM/V
RoT: the lower the voltage input the bigger the propellers that can be attached, the more thrust you can gain (per revolution)
Motor Mount That which attaches the motor to the frame (quite important).
Motor kV = RPM / Battery V or RPM = Motor kV x Battery V
E.g. 3S battery with a 600kV motor: RPM = 600 x 11.1 = 6660 RPM (without load)
This will start to make sense as soon as wel reach the propellers.
Another well known formula:
W(watt/power) = V(voltage) x I(ampere)
Suggested motors: 600kV or lower
http://www.hobbyking.com/hobbyking/...y_4206_530kv_Brushless_Multi_Rotor_Motor.html
(68g x 6 = 408g)
( x 7 = 147)
propeller adapter
is attached to the motor and the propellers are attached to it. Included with motor.
Propeller
The blades that make the craft fly. Specifications:
Diameter the length of the entire blade or the virtual circle the propeller generates.
Pitch amount of travel per revolution (inch per revolution) (RoT, low pitch = less vibrations and more overall stable)
When you mount 10 inch diameter prop RPM (originally 6660) of motor will be reduced to 3600 RPM (Revolutions Per Minute). WHY?
60 Revolutions Per Second.
With a pitch of e.g. 3.8 you get 3.8 inch per revolution: so 60x3.8 inch/second = 228 Inch/Sec = 5.7 m/sec
With a pitch of e.g. 6 inch you get 60 x 6 = 360 Inch/Sec = 9.1 m/sec
Suggested propeller:
To prevent unwanted YAW you want the opposite arms to have one CW and one CCW propeller so they rotate in opposite directions. The frame is 550mm which theoretically means that the max propeller radius can be 11 inch but the motors will likely not be on the edge so its safer to keep the manufacturer suggested 8~10 inch.
10x4.5 SF Props Black CW (2pc) CCW (2pc)
http://www.hobbyking.com/hobbyking/store/__25824__10x4_5_SF_Props_Black_CW_2pc_CCW_2pc_.html
(60g. for the four)
So in total (60*1.5 = 90g)
($ 3 x 2 = 6)
Its completely unclear whether the propellers will fit around the shaft of the motors. How do I figure that out?
ESC
Electronic Speed Controller
ESC supplies power from battery but not constant, it varies according to input signal.
ESC also has BEC (Battery Eliminated Circuit). BEC is nothing but 5V output from ESC that can power up receiver, servomotor(for camera gimbal) and FC.
RoTs:
- the Ampere rating of the ESC should be higher than max amp rating of motor (about 1.2 to 1.5 higher).
- It should be programmable
- Go for quality (check user reviews)
The above motors suggests 25 Amp ESC’s while it’s a max 25 A motor, which contradicts this. WHY? I’m aware that things can burn through when to much current is drawn through them so I’ll go with a higher ESC.
Suggested ESC: HobbyKing 30A BlueSeries Brushless Speed Controller
I’m REALLY in the dark here so I just went for the first link I encountered and checked the RoT: http://www.hobbyking.com/hobbyking/...0A_BlueSeries_Brushless_Speed_Controller.html
(28g x 6 = 168g)
( x 7 = 84)
Battery
The fuel for the engine. Specifications:
mAh milli Ampere hours. In short the total amount of energy
C discharge rating. How fast you can discharge the battery
S S stands for the amount of cells in series (which means that the voltage output of each cell is added to the total V.). One cell has an output of 3.7V, hence a 3S outputs 11.1 V and a 4S outputs 14.8.
P Cells can also be put in parallel which increases the current.
Suggested Battery
Well… assuming the motors are correct they draw: 6x25A = 150 A at max thrust. So that’s A LOT (potential overkill ?). Again no clue, so trial and error, lets go for 4S (checked motor and ESC they both can handle it). ZIPPY Compact 4000mAh 4S 25C Lipo Pack has a discharge rate of 25C. So that’s a max of 25 x 4A (4000mA = 4A) = 100 A. We need 150 at least, so that’s not enough.
ZIPPY Flightmax 8000mAh 4S1P 30C makes 8*30 = 240A which is enough but weighs a whooping (845 g.)
()
Transmitter receiver
Suggestion taken from here: Turnigy 9X
http://blog.oscarliang.net/choose-rc-transmitter-quadcopter/
mode 2 is suggested to be the most common for Y-4, so I guess that accounts for Y-6 as well.
Hence:
http://www.hobbyking.com/hobbyking/..._Module_8ch_Receiver_Mode_2_v2_Firmware_.html
(19 g) (receiver module)
()
_____________________CONCLUSION SO FAR_______________________________
Now how do I calculate whether the craft can fly? Taking into account the weight:
| g | $ | |
| Frame | 435 | 21 |
| Land & gimbal | 190 | 118 |
| Gopro | 74 | 0 |
| FC | 14,5 | 13 |
| Motors | 408 | 147 |
| Propellers | 90 | 6 |
| ESC | 168 | 84 |
| Battery | 845 | 64 |
| Wiring | 100 | 10 |
| Receiver | 19 | 60 |
| Total | 2343,5 | 523 |
<tbody>
</tbody>
2343.5 (or 2.4kg). This means I need at least a thrust of 5kg.
Total costs: 523 $ (378 EUR) Leaving out the gopro but taking spare parts into account.
I've got a *feeling* that the motors are too heavy. I've tried using eCalc but that completely eludes me. From what I gathered these motors are optimized for 12" props so I guess something lower is required. On the other hand, I *do* require quite a bit of lift.
pls shoot!
