Motivations and Preliminary Design forMid-Air Deployment of a Science Rotorcraft on Mars

Abstract

Mid-Air Deployment (MAD) of a rotorcraft during Entry, Descent and Landing (EDL) onMars eliminates the need to carry a propulsion or airbag landing system. This reduces the total mass inside the aeroshell by more than 100 kg and simplifies the aeroshell architecture. MAD's lighter and simpler design is likely to bring the risk and cost associated with the mission down. Moreover, the lighter entry mass enables landing in the Martian highlands, at elevations inaccessible to current EDL technologies. This paper proposes a novel MAD concept for a Mars helicopter. We suggest a minimum science payload package to perform relevant science in the highlands. A variant of the Ingenuity helicopter is proposed to provide increased deceleration during MAD, and enough lift to fly the science payload in the highlands. We show in simulation that the lighter aeroshell results in a lower terminal velocity (30 m/s) at the end of the parachute phase of the EDL, and at higher altitudes than other approaches. After discussing the aerodynamics, controls, guidance, and mechanical challenges associated with deploying at such speed, we propose a backshell architecture that addresses them to release the helicopter in the safest conditions. Finally, we implemented the helicopter model and aerodynamic descent perturbations in the JPL Dynamics and Real-Time Simulation (DARTS) framework. Preliminary performance evaluation indicates landing and helicopter operations can be achieved up to +5 km MOLA (Mars Orbiter Laser Altimeter reference).

Mid-Air Helicopter Delivery at Mars Using a Jetpack

“…Only MAHD allows the 64-cm rotors to fit within the 2.65-m aeroshell. Table 2 compares the performance of MSH between the 58 and 64-cm rotors 7 . Compared to an airbag lander, MAHD enables +27% range, +30% hover time and notably +150% payload mass.…”

“…Combined with the reduced weight of a helicopter compared to past rover or lander missions, this reduces the ballistic coefficient of the aeroshell by a factor of two. This means higher entry deceleration at entry, and access to the highelevation terrains never explored on Mars [7].…”

“…In previous work, we explored mid-air deployment of a smaller coaxial Mars helicopter without a jetpack [7]. While flying the rotorcraft directly out the backshell may be the ultimate mid-air deployment, the airspeed at separation on Mars is predicted to be in the 45-60 m/s range, mostly vertical.…”

Rotor Performance Predictions for Urban Air Mobility: Single vs. Coaxial Rigid Rotors

“…New studies delving further into the analysis of these vehicles range topics covering comprehensive and CFD analyses, handling qualities, system design, hazard analysis, and wind-tunnel testing [36][37][38][39][40][41][42][43][44][45][46][47]. Of particular interest to this work are recent studies of mid-air deployment and high rates of descent with these vehicles [48][49][50][51][52]. Some works have also looked at improving the design approach specifically for coaxial and octocopter configurations [53,54].…”