A169

DESIGN: Electrotor-BladeMotor - Concerns & Tasks (all)

Overview:

A listing of Tasks, Potential Concerns and Thoughts, regarding the Electrotor-BladeMotor.

Concerns:

Redundancy:

Can Outrunner motors be located in series?.

Safety:

A breakdown in any one of the 4 planetary gear sets or in any one of the 4 pinions will eliminate any flight control.

Pitch control strength:

Will the torque of the motor (maximum of 9.55lbf-ft) be sufficient to rotate and hold the pitch or must the torque of the planetary reducer be used (maximum of 28.4 lbf-ft).

Rotor RPM:

The craft will have variable RRPM and this may cause a problem due to vibrations at one or more of the operating RPMs.

Rotor Synchronization and Roll:

The addition of extra electrical power to one rotor, to maintain the synchronization of the rotors, will result in that rotor having greater pitch and therefore greater lift. A possible synchronization ~ roll coupling. A slight reduction in the power of the inside blade on the other rotor may overcome this concern.

Rotor-Rotor Synchronization:

It looks like the rotors must have their azimuths > 45º out of phase for them to clash. This includes the chord width. Hopefully, the electrical system can overcome any chance of rotor getting that much out of synchronization.

Downwash on Pilot:

No pilot in his right mind would go up in this thing ~ at least not until 10 years of testing had been done.

Flight Control during Autorotation:

Include capacitors and/or a 'low battery power' sensors. This should provide power for limited flight control and landing.

Loss of Power in a Motor:

All three other motors in the same system will simultaneously have their power cut..

Will the addition of elevators, rudder and ailerons allow for 'run-on landings? These controls might also be an advantage during conventional flight by providing a little faster response to pilot inputs.

Autorotation:

There is no way, currently of consuming the rotors' inertia during an autorotative flare.

Loss of Rotor Synchronization upon Loss of Power:

It appears that is mandatory that the craft can NEVER experience a TOTAL loss of power. Idea; Triple redundancy. Motors with 3 windings in each blade, plus 3 totally independent circuits. and perhaps capacitors as the core in parts of the composite fuselage as additional backup.

Reliability:

Currently, the loss of any electrical item will probably be fatal on a manned craft. There must be redundancy of all electrical items I.e. two independent systems on manned craft at least.

Gears:

Can the gears handle the high RPM.

Frame:

Strength of the frame. Carbon tubes?

Stability of Teetering:

Re: small rotor & no paddle etc. Hub has delta3 (by Control System Geometry).

Tasks (to do):

Xx

Same Page Different Craft: ~ SynchroLite ~ UniCopter

Last Revised: June 7, 2009