I am designing and building a quad-copter. I have an approximate weight list for all the components except the batteries and brush-less motors. I'm looking for motor recommendations for what motor to use as the main lift engines.
I am aware that I need to figure out the total needed current in order to choose a battery but I need to choose what brush-less motors i'll be using first.
Motor1 recommends a 10x4.5 propeller. It might not have the power to swing your 12x6 propellers.
Motor2 is WAY too fast for a 12" propeller. With a 2S battery you can use a motor up to about 1100kv. For a 3S battery you have to drop to around 800kv.
Motor3 says suitable for 300-400 size (that's diagonal motor to motor). You need a 450 or bigger frame if you don't want your 12" propellers hitting each other.
Motor4 is even faster than motor2. Way too fast for 12" props.
Motor5 is almost as fast as motor4. Way too fast for 12" props.
Looks like motor1 would be your best bet but may burn up trying to push 92% more air (44% larger prop area times 33% higher pitch)
I went on to RCgroups they helped, but only a bit.
Link Here
I've created a new list of 5 motors on the above forum. They seem to be much more realistic; low kv's.
They directed me to two sites that are pretty useful for choosing components, but they don't leave room for custom built frames. (which is what i'm building)
I can change the prop length, but a longer length would be ideal. I'll start looking into comparing motor1 to the weight ratio, flight time, and prop length.
The maximum propeller size depends on the frame size. Either pick the frame and then pick propellers that fit or pick propellers and then pick/design a frame that fits.
The motors depend on the propellers. Pick motors that recommend the diameter and pitch of propeller that you have chosen. Larger propellers require slower motors (lower 'kv' rating).
The battery voltage depends on the motors. The motors will specify their design battery voltage, usually by stating the number of 3.7V LiPo cells in series (1S, 2S, 3S...).
ESC's depend on the battery voltage and the motor maximum power draw. If your motor specifies Watts instead of Amps you divide Watts by the battery voltage to get Amps. If the ESC's are "Opto" they don't provide a 5V output to power the flight controller, radio, and any servos. In that case you need a Battery Eliminator Circuit (BEC) which is what the RC people call a DC-to-DC converter. Some Power Distribution Boards have a BEC built in. Some commercial frames have a Power Distribution Board built in.
Everything else: Radio, Flight Controller, Servos (if any) is generic and runs off 5V from an ESC or BEC.
The frame will be custom made. I've just done a course on electricity so the physics of the voltages and currents won't be problematic anymore. As for the ESCs will I need one for each of my brush-less motors? Or is there multiple (4) data inputs to regulate the brush-less motors speed on the ESC?
Immortal_Conqueror:
As for the ESCs will I need one for each of my brush-less motors? Or is there multiple (4) data inputs to regulate the brush-less motors speed on the ESC?
It might be an idea to buy and build a simple RC plane kit, often referred to as 'park fliers'.
They are often close to fully assembled but at low cost you get something that flies and introduces you into the basics of RC flight, transmitters, receivers, motors, batteries, speed controllers (ESCs) etc.
I'd like to build and design my own. This is mostly for the learning experience. Plus I've already cracked hours into research so the learning experience that 'park fliers' would be pretty limited at this point. Also I've put plenty of time into building the flight controller from scratch and have already begun buying the parts. (not the ones that are still being decided on)
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Oh, another thought.
Have you ever flown a quad before?
I think that it would be valuable experience for you.
There are many relatively easy to fly models out there that are crazy cheap.
Google "hubsan quad nano"
Get 2 of them.
Immortal_Conqueror:
I've already cracked hours into research so the learning experience that 'park fliers' would be pretty limited at this point. Also I've put plenty of time into building the flight controller from scratch and have already begun buying the parts. (not the ones that are still being decided on)
Your designing and building your own flight controller, yet you do not have enough (any ?) exeperience of radio control stuff that tells you its normally one ESC per motor ?
srnet:
Your designing and building your own flight controller, yet you do not have enough (any ?) exeperience of radio control stuff that tells you its normally one ESC per motor ?
Radio controls have almost nothing to do with ESCs. ESCs are in the electrical field for quad-copters, which are needed to supply voltage to the brush-less motors. Your connection between the two isn't sound...
vinceherman:
Oh, another thought.
Have you ever flown a quad before?
I think that it would be valuable experience for you.
There are many relatively easy to fly models out there that are crazy cheap.
Google "hubsan quad nano"
Get 2 of them.
I've flown quads before, but thanks, I'll get one or two to use as mini-models for their electrical functions as well as for practicing my quad flying skills.
Immortal_Conqueror:
Radio controls have almost nothing to do with ESCs. ESCs are in the electrical field for quad-copters, which are needed to supply voltage to the brush-less motors. Your connection between the two isn't sound...
Fair enough, I stand corrected.
I mentioned it since just about every Radio Controlled model that I have built or converted to electic power in the last 30 years had 5 basic parts, Plane, Motor, Radio Control, Battery and of course the ESC.
Immortal_Conqueror:
Radio controls have almost nothing to do with ESCs. ESCs are in the electrical field for quad-copters, which are needed to supply voltage to the brush-less motors. Your connection between the two isn't sound...
Apart from the minor fact that ESCs are designed for RC models and to be controlled by the servo signals from RC receivers. If you don't understand those RC servo signals you'll have trouble controlling brushless motors via their ESCs.
Still if you know so much about it I guess you won't be needing any more help.
slipstick:
Apart from the minor fact that ESCs are designed for RC models and to be controlled by the servo signals from RC receivers. If you don't understand those RC servo signals you'll have trouble controlling brushless motors via their ESCs.
Still if you know so much about it I guess you won't be needing any more help.
Steve
To be fair ( and extra picky ), I haven't used a quad with standard parallel pwm servo signals for a few years now. Serial from the receiver and either a short pulse pwm ( oneshot, multishot ) or digital signal ( dshot) to the esc's from the flight controller. Still, good to know how servo signals work in general as its the easiest way to interface with the esc's and an arduino.
slipstick:
Still if you know so much about it I guess you won't be needing any more help.
Steve
I don't know about that xD. I know how to work with servos but the main issue i'm having is how to utilize ESCs (as in the programming portion) to control the brush-less motors speed. I've a discussion going on in the programming division of the forum.