For Landers

NGC provides autonomy-enabling Guidance, Navigation and Control (GNC) software solutions for planetary landers, covering all phases of the descent, from de-orbiting until touchdown. The expertise is particularly focused toward autonomous systems requiring Hazard Detection and Avoidance (HDA) for safe landing and Vision-Based Navigation for Precision Landing. NGC provides such GNC systems for Moon, Mars or Asteroid exploration missions.

Guidance, Navigation and Control for Landers

Moon Landing Applications

NGC provides complete end-to-end services for the design and implementation of the GNC software required for autonomous Moon landing missions, including inertial and Vision-Based Navigation, Lidar-based Hazard Detection and Avoidance (HDA), trajectory design as well as guidance and control for braking, soft landing and Precision Landing. These were developed in an on-going series of technology development programs of the Canadian Space Agency (CSA) as well as mission programs and concept studies supported by the European Space Agency (ESA).

Lunar Lander

ESA Lunar Lander (Artist Conception) (© ESA, Source)

Mars Landing Applications

NGC provides the complete end-to-end design and implementation of the GNC software for Mars landing missions, including guided entry, inertial navigation, atmospheric parameter real-time identification, adaptive flight-path angle guidance, bank-angle control and Lidar-based HDA.

Mars Sample Return

ESA Mars Sample Return Mission Concept (Artist Conception) (© ESA, Source)

Asteroid Exploration Applications

NGC’s expertise extends to the design, validation and analysis of GNC software for asteroid rendezvous or asteroid trajectory deflection missions.

Comet Tchouri

Rosetta navigation camera image of Comet 67P/Churyumov-Gerasimenko (© ESA/Rosetta/NavCam – CC BY-SA IGO 3.0, Source)

Rosetta & Comet

ESA Don Quijote Asteroid Deflection Precursor Mission Concept (© ESA – AOES Medialab, Source)

Vision-Based Navigation

In order to meet Precision Landing requirements of future planetary exploration missions, NGC provides state-of-the-art image processing software for terrain-relative navigation, covering both absolute navigation (determination of absolute inertial position, velocity and orientation) and relative navigation (determination of surface-relative motion). Absolute navigation is realised by matching detected craters with an on-board crater map while relative navigation is performed by comparing successive images. The image processing software is complemented with extended Kalman filtering algorithms to provide real-time state estimation during the descent sequence. The technology put forward for landing applications shares many components with rover vision-based navigation technologies.

Feature Tracking for Landing

Relative Navigation with Feature Tracking

Crater Detection

Absolute Navigation with Crater Detection and Matching

Lidar-Based Navigation

NGC pioneered the use of Lidar technologies to perform position determination for landing applications. This technology determines the lander map-relative position by comparing a processed Lidar scan with a reference map of the area. These solutions have also been extended to rover applications.

Lidar-Based Navigation

Lidar-Based Navigation

High-Fidelity Engineering Simulators

In order to verify and validate autonomous flight software prior to launch, NGC develops low, medium and high-fidelity simulators for space vehicles. These engineering simulators consist in the numerical representation on computers of the sensors, actuators, dynamics and environment of the space vehicle so its closed-loop behaviour can be accurately reproduced and its performance in the real environment of space can be predicted with high accuracy and reliability. Low and medium-fidelity simulators are typically used in the design phases of a space vehicle where a rough assessment of stability and performance is required. High-fidelity simulators are used in the later stages of a project where parametric and statistical analyses of the system are evaluated in terms of its robustness and sensitivity to parameter uncertainty and varying operational and environmental conditions. The various simulators include:

  • attitude and orbital dynamics of an orbiting space vehicle,
  • attitude and orbital dynamics of vehicles flying in a formation,
  • attitude and orbital dynamics of vehicles during rendezvous and capture,
  • coupled attitude and trajectory dynamics of a landing vehicle.

High-Fidelity Hardware-in-the-Loop Emulators

As a complement and extension to computer simulations, the NGCLAB provides the emulators and equipment to conduct Hardware-in-the-Loop (HIL) simulations. The main objective of these HIL simulations is to immerse the flight software in the realistic operational conditions of its future environment including the measurements generated by a real sensor and the processing power of a real flight-like real-time computer. Some physical processes are too complex to model and simulate with high accuracy (e.g. Lidar instrument interaction with the terrain). Using the real sensor hardware avoids this complexity. Furthermore, these complex physical processes require so much computing power that they make real-time simulations impossible. Replacing them with real hardware avoids this problem.

The various equipment in the NGCLAB include the Landing Dynamic Test Facility (LDTF), a 6 degree-of-freedom mechanical arm mounted on a rail system that emulates the scaled, closed-loop motion of a planetary landing vehicle using real sensors (camera, Lidar, inertial measurement unit) as well as a flight-like processor in the loop

NGCLAB

NGC Landing Dynamic Test Facility (LDTF)