This question is an exact duplicate of:

I am planning to build a quadcopter, so I searched about motor drivers, then I thought "Do I really need a motor driver?", I mean the only thing I want to control is the motors' speeds, so won't MOSFET be enough for that?


marked as duplicate by Chris Stratton, Dave Tweed Jan 20 at 0:40

This question was marked as an exact duplicate of an existing question.

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    \$\begingroup\$ Yes, you really do need motor drivers. I recommend you look up just how the kinds of motors used in quadcopters work; they're usually three-phase permanent-magnet AC motors. \$\endgroup\$ – Hearth Jan 19 at 14:57
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    \$\begingroup\$ For a start, how will you get velocity (RPM) feedback to your control system if you use a simple DC motor? \$\endgroup\$ – Transistor Jan 19 at 15:04
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    \$\begingroup\$ What happens if something blocks the rotor? \$\endgroup\$ – Hearth Jan 19 at 15:28
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    \$\begingroup\$ How precisely can you control motor speed using just a MOSFET? How precisely do you need to control speed in order to maintain stable flight? Do every motor and every MOSFET have exactly the same characteristics? \$\endgroup\$ – Elliot Alderson Jan 19 at 15:36
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    \$\begingroup\$ Quadcopter motors are not controlled for a desired speed, rather the loop is closed around the behavior of the aircraft. Small ones using brushed motors do indeed use a single FET per motor PWM'd from the processor. Spend some time working with an open source firmware reflashed into a 20 gram toy before you think about doing anything fully original or larger. The wildly ignorant replies you are getting demonstrate why you should pursue experiential knowledge somewhere like rcgroups rather than guesses from first principles here. \$\endgroup\$ – Chris Stratton Jan 19 at 17:05