Suspended RC Plane Landing Gear
I needed to improve the takeoff, landing, and ground handling performance of an RC plane. My goal was to model and build suspended gear for the RC plane and move the gear forward. In one day, I designed, constructed, and integrated the new landing gear. The new landing gear significantly enhanced the plane's takeoff, landing, and ground handling performance by eliminating noseovers and bouncy landings.
Problem
From the factory, the Volantex Ranger EX has very rearward placed main landing gear which makes nose overs on the ground very easy. Landing? Nose over. Taxiing? Nose over. Also, the landing gear was quite stiff which make it difficult to keep on the ground while landing. So there were two issues to solve, nose overs and suspension of the landing gear.
Design
I decided to use a cross cable/bungee cord style suspension system which is used by Super Cubs and other small bush airplanes. It seemed like an easy system to manufacture quickly. This ended up being true as I modeled and built the landing gear in a day.
I modeled the replacement internal supporting structure and landing gear system using Onshape. I neglected modeling the wheels and steel wires for the sake of time savings. The carbon fiber internal structure replaced the plywood structure that was present from the factory. The landing gear assembly was made using 1.5 and 3.0 mm carbon fiber plate.
Manufacturing
I used Fusion CAM to program a CNC router to cut 1.5 and 3.0 mm carbon fiber plate to construct the mount of the suspended landing gear.
I 3D printed aerocovers for the mount and fabricated pivot joints using 3/8" aluminum rod and grinding down a flat face to design dimension. I drilled and tapped two holes on each joint for M3 screws to mount the landing gear struts.
The carbon fiber internal structure was a sandwich of 1.5 mm plate, brass standoffs, and another 1.5 mm plate. The bottom plate was for mounting the landing gear and the top plate was there to mount the flight battery.
The pivot joint that the landing gear strut mounts to.
I used thin steel wire and some springs I found on an old drone to make the cross cables.