HobbyKing.com New Products Flash Sale
Reply
Thread Tools
Old Jul 10, 2014, 03:16 PM
Registered User
Joined Jul 2014
1 Posts
Discussion
variable pitch quad copter design ideas + questions

hi, i have been working out a design for an electric quad copter with 450 size heli main rotor heads and 325mm blades

can anybody tell me if it will be beneficial to keep the 3 point cyclic pitch control on the rotor heads from the perspective of efficiency and flight performance?

i have a couple of ideas for both a belt driven design and a torque tube bevel gear design.
but in order to develop one further i need to work out the optimum gear ratio and motor size and find wich design will accommodate the best gear ratios

can anybody suggest how i can go about working out a good gear ratio?

i have a couple of e-calc readouts but im unsure if have entered the correct values for the props

here is the e-calc screenshot:



here is a rough sketch of an idea i have:



there would be a central circular block with 6 bearings pressed into it, one for each of the torque tubes and one for each of the bevel/spline main drive gears

each apposing pair of torque tubes would be driven by either the top or the bottom main gear this would be possible by offsetting their corresponding bearings in the central block, this would mean each torque tube would also be off center inside the arms of the copter

in between each arm of the copter i would mount 4 motors, 2 driving each main gear 2 with the pinnion at the top and 2 at the bottom

can any body see any inherent flaws in this idea?
the only problem i can see is that the central block is essentially floating and held only by one end of each gear shaft

im not sure if i should go with 3s or 6s, also low kv or high kv motor
my aim will be a heavy lift copter with a reasonable flight time 15-20mins

a rough shopping list so far:



does anyone know if this type of carbon tube will have the torsional strength to be used as a drive shaft?
blrh93 is offline Find More Posts by blrh93
Reply With Quote
Sign up now
to remove ads between posts
Reply


Thread Tools

Similar Threads
Category Thread Thread Starter Forum Replies Last Post
For Sale Cool Bi-Copter with Variable Pitch Tail Rotor AtomicPunk Aircraft - Electric - Multirotor (FS/W) 10 May 30, 2013 05:12 PM
Build Log Variable pitch multi-rotor copter :: Development Stage outsider787 Multirotor Talk 267 Jan 29, 2013 12:10 PM
Discussion The V-Pitch Variable Pitch Prop motor...quad? docinfrance Multirotor Talk 33 May 11, 2012 05:36 PM
Discussion Variable pitch quad copters? GreenAce92_v2 Multirotor Talk 4 Mar 06, 2012 12:21 AM
New Product You thought you had a cool quad...new variable pitch prop quad!! Bigcats30 Multirotor Talk 3 Feb 28, 2012 04:22 PM