motors

Assessing motor merits (or, rather, communicating them) requires a common understanding of your value system. Does efficiency rule your value system (in an electric multi rotor, I believe it should given the state of battery technologies today) or do you other specific requirements? Flight time, lift capability, intended application (is this a fun fly/acro craft, or is it intended as a hover/photo platform, or will it be something in the middle, for example)

If efficiency is not a concern, then the engineering can be much less precise.

With these motors, you have a weight issue, sure, but the mounting issue may be more significant. Questions of efficiency rely on all the things I have mentioned before. If you do want to pursue efficiency, I wanted to bring your attention to an invaluable resource http://www.flybrushless.com/

Spending sometime there looking at general thrust windows, RPM windows for different props, Watt requirements for different thrust yields, then matching a motor that can deliver its most efficient performance at those RPM/Watt ranges is what you want to do. The weight of the motors is not an issue if the system is efficient, most motors will easily lift themselves, at 200% or more of their own weight. As long as you've designed an efficient system everywhere else, choosing a more efficient motor for your weight range is vastly more important than the weight of the motor itself (in anything but mini/micro multi rotors...)

Just some things to think about.... and good luck!

PS - the 880 and 850 motors from jDrones are really very good motors.... I've done the math, and I encourage you to do the same....

Replies

Moderator

Michael Pursifull May 1, 2012 at 8:32am

Assessing motor merits (or, rather, communicating them) requires a common understanding of your value system. Does efficiency rule your value system (in an electric multi rotor, I believe it should given the state of battery technologies today) or do you other specific requirements? Flight time, lift capability, intended application (is this a fun fly/acro craft, or is it intended as a hover/photo platform, or will it be something in the middle, for example)

If efficiency is not a concern, then the engineering can be much less precise.

With these motors, you have a weight issue, sure, but the mounting issue may be more significant. Questions of efficiency rely on all the things I have mentioned before. If you do want to pursue efficiency, I wanted to bring your attention to an invaluable resource http://www.flybrushless.com/

Spending sometime there looking at general thrust windows, RPM windows for different props, Watt requirements for different thrust yields, then matching a motor that can deliver its most efficient performance at those RPM/Watt ranges is what you want to do. The weight of the motors is not an issue if the system is efficient, most motors will easily lift themselves, at 200% or more of their own weight. As long as you've designed an efficient system everywhere else, choosing a more efficient motor for your weight range is vastly more important than the weight of the motor itself (in anything but mini/micro multi rotors...)

Just some things to think about.... and good luck!

PS - the 880 and 850 motors from jDrones are really very good motors.... I've done the math, and I encourage you to do the same....
Moderator

Michael Pursifull May 1, 2012 at 7:56am

what is the application? how do you plan to use them?

This reply was deleted.

Discussions

motors

Replies

Activity