Kryptodrakon

Description

Pterosaur with a foam-centered head rudder.

Development Log

2022-04-18 — Kryptodrakon test 17.04.22
2023-01-28 — Kryptodrakon new head rudder control — The kryptodrakon was well able to fly without head, but with head crest in front of CG larger controll surfaces would be required because passive stabilization is working well only to some extent. Therefore a head rudder system was implemented that uses foam to help to center the head to the middle and a transmission by two push rods was used to make good use of servo travel range . Also probably a gyro will be required to make the head rudder system controllable. Another change is that The gullwing dihedral is now adjustable by bending a 5mm steel tube that was used to make the hinge, I don’t know how durable this solution is in the long term…
2023-06-14 — Kryptodrakon test 13.06.23 — two servos were added for twisting the wingtips by a piano wire, which creates a rudder by inducing/decreasin drag on either wing. however the effect is still too marginal to ensure enough controllability, besides it is difficult to make the wings equal because a steel pipe was bent and used as gull wing anhedral joint… then there is an issue in the gearbox that needs repairing. However some test show that the model is able to fly when enough control can be established. I will try to improve the deficiencies of the current model, increase control effect by larger servo horns and add a gyro for stabilization. I am also considering putting back one servo for head rudder control, but more weight is not good, and extra parts at front are easier to break on crash