albatrosmodel
Sep 15, 2008, 12:23 PM
Hi you widget craftsmen all over the world,
How about a SLIP/SKID compensator for our flying machines?
ALL flying craft benefit from staying aligned with the relative airflow (less drag, stay in manoeuvring and stability envelope).
Common exercise is: tediously practised coordinated turning and/or coupled aileron/rudder steering. But can anyone honestly SEE the fuselage alignment at 600 m distance or is it presumed skill between the ears? I did tests using yaw strings on my F3J glider, that were video evaluated. Outcome: slipping and skidding all over the place, except for 1 specific speed/bank state. Read Helmut Reichmann and appreciate that 1 state being the exception in performance flying. Especially hanggliders, parapentes, ultra lights, gliders, radio controlled models, UAV etc etc. Especially R/C glider and UAV performance and/or endurance would vastly improve when a more automated/ intuitive skid/slip control system were available.
Don’t confuse this with YAWING (a inertial turning) or CRABBING (a course/heading difference over ground). The common turn/slip indicator instrument is purely inertial and relates bank, speed and turn radius. For crabbing we use dead reckoning an GPS navigation telling us which heading to fly in relation to course. The YAW string instrument used on gliders is more like what is needed, a state of the art HUD indicator. But our reflexes still have to interfere (step rudder opposite string) and it still has to be used with brains ON (the nose is ahead of the aerodynamic/gravitational centre, so in turns never keep it in the middle unless you want to CREATE drag).
Why bother? Apart from the performance issue above, I see 2 interesting applications:
1. Fins/rudder on flying wing concepts (whether real planks or bird-wing shaped or V/Stromberg shaped) could be discarded by other means of yaw control (spoilers, brakes). Realistic looking bird models, dinosaur replica’s, R/C competition gliders.
2. Rudder input could be automated on glider/UAV concepts to eliminate any adverse or advantageous yaw tendencies. Proper layout of control hysteresis could eliminate damping. Extended performance, endurance, relaxation.
Is it too much asked for? Just to have the sensor/probe that measures the airflow direction/velocity difference between left and right? Just the chip/counter IC that delays the rudderservo(s) pulse as in a mixer?
It seems to me even as an electronic layman that this should be very easy to construct. In fact a club friend of mine did produce a working prototype, but it depends on a wind vane probe and has only digital control (Left OR Right, not a little more or less analogous control). Besides it proofed the wind vane/pot meter arrangement has too much friction and subsequent hysteresis. Mousewheel like opto devices might be the answer. I have seen all the electronic gadgets parading by so far: altimeters, loggers, gps readouts, speed, heading, variometers etc.etc. Even on model R/C controlled submarines they have differential pressure controls.
Now for the last but certainly not the least effective gadget here is your challenge. The first to be in business will earn the millions.
Be inventive, make our day(s).
Or am I naïve? So tell me the truth.
Regards, Albatrosmodel.
http://albatros.backpackit.com/pub/689461
http://www.rcgroups.com/forums/showthread.php?t=897603&page=5&highlight=albatross
How about a SLIP/SKID compensator for our flying machines?
ALL flying craft benefit from staying aligned with the relative airflow (less drag, stay in manoeuvring and stability envelope).
Common exercise is: tediously practised coordinated turning and/or coupled aileron/rudder steering. But can anyone honestly SEE the fuselage alignment at 600 m distance or is it presumed skill between the ears? I did tests using yaw strings on my F3J glider, that were video evaluated. Outcome: slipping and skidding all over the place, except for 1 specific speed/bank state. Read Helmut Reichmann and appreciate that 1 state being the exception in performance flying. Especially hanggliders, parapentes, ultra lights, gliders, radio controlled models, UAV etc etc. Especially R/C glider and UAV performance and/or endurance would vastly improve when a more automated/ intuitive skid/slip control system were available.
Don’t confuse this with YAWING (a inertial turning) or CRABBING (a course/heading difference over ground). The common turn/slip indicator instrument is purely inertial and relates bank, speed and turn radius. For crabbing we use dead reckoning an GPS navigation telling us which heading to fly in relation to course. The YAW string instrument used on gliders is more like what is needed, a state of the art HUD indicator. But our reflexes still have to interfere (step rudder opposite string) and it still has to be used with brains ON (the nose is ahead of the aerodynamic/gravitational centre, so in turns never keep it in the middle unless you want to CREATE drag).
Why bother? Apart from the performance issue above, I see 2 interesting applications:
1. Fins/rudder on flying wing concepts (whether real planks or bird-wing shaped or V/Stromberg shaped) could be discarded by other means of yaw control (spoilers, brakes). Realistic looking bird models, dinosaur replica’s, R/C competition gliders.
2. Rudder input could be automated on glider/UAV concepts to eliminate any adverse or advantageous yaw tendencies. Proper layout of control hysteresis could eliminate damping. Extended performance, endurance, relaxation.
Is it too much asked for? Just to have the sensor/probe that measures the airflow direction/velocity difference between left and right? Just the chip/counter IC that delays the rudderservo(s) pulse as in a mixer?
It seems to me even as an electronic layman that this should be very easy to construct. In fact a club friend of mine did produce a working prototype, but it depends on a wind vane probe and has only digital control (Left OR Right, not a little more or less analogous control). Besides it proofed the wind vane/pot meter arrangement has too much friction and subsequent hysteresis. Mousewheel like opto devices might be the answer. I have seen all the electronic gadgets parading by so far: altimeters, loggers, gps readouts, speed, heading, variometers etc.etc. Even on model R/C controlled submarines they have differential pressure controls.
Now for the last but certainly not the least effective gadget here is your challenge. The first to be in business will earn the millions.
Be inventive, make our day(s).
Or am I naïve? So tell me the truth.
Regards, Albatrosmodel.
http://albatros.backpackit.com/pub/689461
http://www.rcgroups.com/forums/showthread.php?t=897603&page=5&highlight=albatross