Sunday, October 31, 2010

The Pantheon by David Moore

The Pantheon by David Moore: "This famous building stands in the business district of Rome--much as it was built some 18 centuries ago. Amazingly, it has withstood the ravages of both the elements and war permitting a firsthand view of a unique product constructed by Roman hands. Now, it is exposed to acid rain and fumes from passing automobiles and overshadowed by buildings of inferior taste; but, with trust in the future, the Pantheon will survive."

Saturday, October 30, 2010

Differential ailerons

Differential ailerons: "There is a simple way of accomplishing differential aileron throws mechanically, by positioning control horns away from the hinge of the control surface. On this page we provide simple charts that allow one to measure and position aileron control horns to get precise maximum throw angles while achieving the desired differential."

Friday, October 22, 2010

what is DEPRON

what is DEPRON: "Depron is actually polystyrene (EPS/XPS) plastic and the (EPS) means expanded while (XPS) means extruded. For our purposes, we’re only interested in the stronger, denser XPS Depron which also happens to be closed-cell foam."

Depron Foam - Technical Information

Depron Foam - Technical Information: "Below are links to the current Depron Foam technical information:"

Monday, October 18, 2010

Untitled Page

RP Flight Systems: "The Spectra line of unmanned aircraft have been developed as an 'unclassified' asset, meaning there are no 'dual use' or military equipment installed that would produce data that would have to be 'declassified' before distribution."

Friday, October 15, 2010

RC Glossary

The Ultimate RC Flying Glossary!: "This RC flying glossary contains some of the more common words and terms that you'll hear now and again when you're reading about rc airplanes, or you're down at the flying field."

Wednesday, October 13, 2010

Draganflyer X4 Four Rotor UAV Helicopter Aerial Video Platform

Draganflyer X4: "The small, battery powered Dragaflyer X4 gets you the same great aerial pictures that renting a plane can, but at a fraction of the cost. Avoid the hassle and expense of using a full size aircraft for projects that can be accomplished easily and economically with our Draganflyer X4 UAV."  One of the original commercial units, and a steal at only $8,000!

Thursday, October 7, 2010

Basic Servo Motion

Stick/Servo Relationship

rudder   L = CCW, R = CW 
aileron  L = CCW, R = CW 
elevator F = CCW, B = CW

Non-Reversing Installation

rudder             elev 
servo stem  horn   servo stem   horn 
----- ----  ----   ----- ----   ---- 
left  top   left   left  top    bottom 
right top   right  left  bottom top 
down  left  left   right top    top 
down  right right  right bottom bottom 
                   up    left   top 
                   up    right  bottom 
                   down  left   bottom 
                   down  right  top

Plausible Rudder/Elevator Combinations

DRR/DLB (inverted, for ezflyer)
LTL/RTT (flat, on top, 300s)
RTT/RBB (2 rights, above and below wing)
LTL/RBB (stacked, flat, around wing)
LTL/LBT (left, high, up and down)
Best configuration for RET (rudder/elevator/throttle) flyer (e.g. Blu-Baby) with push rods on outside of plane

rudder             elev 
servo stem  horn   servo stem   horn 
----- ----  ----   ----- ----   ---- 
left  top   left   right top    top

The Fleet: H-6, Nutball 17

202g (7.1oz) AUW w/ 2S 500mah
paint added 3g

Tuesday, October 5, 2010

Balancing servo throws

from: Setting up your Airplane
 Preferred servo orientation to maximize stiffness:

Linkage setup:
  • dimensions "A" and "B" are determined by what the plans call for with respect to the total movement of the control surface (up/down, left/right, etc.) and how much travel your servo has.

    set radio for normal, high-rate throws.
  • at control surface, mount the control horn so that distance "A" is as large as possible -- about 1" or so for large aircraft, 3/4" or so for smaller airplanes; commensurately larger for giant scale or smaller for park flyers.
  • deflect the control surface to the maximum the plans call for, and measure the (horizontal) distance that the hole in the control horn moves. Call this dimension "C".
  • Using radio, center servo arm.  run the servo to its extremes and measure the distance some particular hole in the servo arm moves. Choose the hole that is closest to dimension "C" that you measured at the control surface. The distance from the middle of the servo attaching screw to that hole is dimension "B".
  • fix control surface in neutral position, and measure the distance between the hole on the servo arm and the hole in the control horn with the servo in its neutral position.
  • manufacture a straight rod and attach it to those points.
  • mount the servo, making sure that the servo arm is perpendicular to the control rod, as shown, and that the control horn is also perpendicular to the rod.
  • turn on your radio again and run that channel to its extremes and measure the throws at the edge of the control surface. Now reference the plans for your model. Are the throws too much, too little, or just right? If too much, increase dimension "A" (or decrease "B").  If too little, reduce "A".
  • the throws in each direction should be identical. If not, check that the setup is as shown above, with 90 degree angles at both ends. You may have to adjust the neutral on your servo, or bend the arm at the control horn, but try hard to equalize those throws!
  • What you’re doing here is maximizing the utilization of your servo’s power. By using the entire rotation of your servo arm to cause the control surface to move its maximum distance, you’ve used the mechanical advantage of the servo to its fullest extent - all the power your servo has is being used.
  • If you merely install your servo and rod without regard to the total desired control throws, and the distance "B" at the servo is longer than at the control arm, you will have to reduce the maximum servo arm rotation allowed in order to keep the control surface movement at the correct distance. Result: poor utilization of your servo's power—you’re only using part of it, and resolution suffers as well.
  • If distance "B" at the servo is shorter than at the control arm, the opposite ensues, and you’ll most likely overdrive the servo, perhaps causing binding or other equally devastating problems, or you won’t get the full throws desired at the control surface.

EZ-Pod Kit [PT-EZ] : RangeVideo!, Wireless video solutions.

EZ-Pod Kit [PT-EZ] : RangeVideo!, Wireless video solutions.