CCPM advice

[Azhar]

Good Day

I am working on a project which entails developing an algorithm capapble of carrying out the mixing function electronically for a single rotor (5 bladed) helicopter. I do not have much experience with rotary wing aircraft and have espent the last few days getting aquainted with the control characteristics pertinent to such aircraft.

In particular I need to obtain the relationship between the control inputs (collective & cyclic) and the actuator displacements which will produce the correct change in blade pitch. The actuators are attached to the lower, non-rotating swash plate. This information is vital for developing the algorithm - or rather, this is what I have assumed. Additionally, the algorithm should be capable of minimising the cross-soupling between inputs by pre-empting the cyclinders to take the appropriate corrective action when a certain control input/s is applied. Essentially the goal is to determine the mathematical relation between the control input and actuator displacement such that the mixing function is incorporated.

Could anyone kindly assist by pointing me in the correct direction to tackle this problem or additionally, advise as to appropriate references which would aid in helping me gain a fundamental understanding of the factors involved.

Many Thanks in advance

Any assitance would be greatly appreciated

[extrapilot]

Azhar

There are many texts which describe control system/actuator theory. Rotary wing is substantially more complex than most realize; you will find that coupling is often beneficial, and that the rotor dynamics change dramatically in transitory flight, in autorotation, etc.

I would start with the classic reference materials; they approach these problems mathematically, but will also provide you the background you will need to get a decent start on your work:

Principles of Helicopter Aerodynamics, Gordon Leishman
Rotary-Wing Aerodynamics, Stepniewski/Keys
Helicopter Dynamics, Bramwell

[Azhar]

Extrapilot

I appreciate your input and will have a look at those texts. Thank you very much.

Have a great day