An Investigation into Metal-Based Energy Absorption Systems for Usage on Rotorcraft Landing Skids: Addressing Hard Landings and Repeated Impact Scenarios

Energy absorption systems on rotorcraft are widespread and commonly centered around fluid-based designs. However, damping systems that rely on fluids are not feasible for applications in extreme and cryogenic conditions. With the rise in autonomous rotorcraft that fly on planets other than Earth, a new energy absorption system must be developed that can meet the challenges these types of environments present. These designs must also be simple and require virtually no maintenance, as they will be isolated in space. The Ingenuity Helicopter employed an innovative energy absorption mechanism using two conjoined metallic spring-like disks—one made of titanium and the other of aluminum. Upon landing, the aluminum disk underwent plastic deformation to absorb impact energy, while the titanium disk provided a restoring force for repeated use [9]. A series of FEA simulations were conducted to study the system implemented on the ingenuity rotorcraft. Analysis began by simulating the compression of an aluminum and titanium pillar constrained by a rigid base. This allowed for the observation of the energy absorption of the aluminum pillar and the restorative force of the titanium pillar. A novel system of energy absorption using the principles of Ingenuity was also proposed and analyzed. This system consisted of a cylindrical aluminum core encased inside a titanium shell. Overall, several key findings were obtained through the simulations performed. It was found that as the aluminum plastically deformed at 590 microstrain, the titanium remained in the elastic region. This was true for both models analyzed. Further, an approximate energy to force applied ratio of 0.0024 J/N was obtained from each simulation. Additionally, both models featured a total plastic energy dissipation of just over 12J.