Alternatives for Autonomous Navigation of Small Solar System Explorers
G. González Peytaví, A. Probst, T.P. Andert, B. Eissfeller, R. Förstner
5th Interplanetary CubeSat Workshop, Oxford, UK, 24-25 May 2016
5th Interplanetary CubeSat Workshop, Oxford, UK, 24-25 May, 2016
• Distributed networks in Solar system exploration
• Autonomous navigation – What for?
• AutoNav alternatives – Absolute navigation – Relative navigation
• Evaluation of alternatives
Outline Alternatives for Autonomous Navigation of Small Solar System Explorers
The next 20 minutes…
Increase spatial
coverage
Cooperative Remote Sensing
Increase temporal coverage
Larger baselines
Multi-node experimentation
Controlled baselines
Separation of payload
critical modules
Mission safety Spatially
distributed redundancy
5th Interplanetary CubeSat Workshop, Oxford, UK, 24-25 May, 2016
Distributed networks in Solar system exploration Alternatives for Autonomous Navigation of Small Solar System Explorers
Cooperative Scientific Exploration and Prospection
Attractive solution • reduced launch mass
increments
Strong dependency on SC master • Propulsion • Communication • Navigation
Interplanetary CubeSat Networks
5th Interplanetary CubeSat Workshop, Oxford, UK, 24-25 May, 2016
Autonomous Navigation – What for? Alternatives for Autonomous Navigation of Small Solar System Explorers
During interplanetary cruise
Self-reliant course corrections
Independent targeting/observation sequences
Reduce contact to ground-control for orbit determination
During proximity operations
Near-real time mission planning
Independent surface targeting/observation sequences
Support investigations of trajectory perturbing phenomena
(gravity, radiation, drag, etc.)
Why AutoNav?
𝑂 𝒓� = 100 𝑘𝑘 ,3𝜎 trajectory planning 𝑂 𝒓� = 10 𝑘𝑘 , 3𝜎 rendezvous planning
𝑂 𝒓� = 1⋯100 𝑘𝑘 ,3𝜎 during fly-by 𝑂 𝒓� = 100 𝑘 , 3𝜎 small-body orbiting 𝑂 𝒓� = 1 𝑘 , 3𝜎 small-body landing
5th Interplanetary CubeSat Workshop, Oxford, UK, 24-25 May, 2016
Alternatives – Absolute Navigation Alternatives for Autonomous Navigation of Small Solar System Explorers
Absolute Navigation
5th Interplanetary CubeSat Workshop, Oxford, UK, 24-25 May, 2016
Alternatives – Absolute Navigation Alternatives for Autonomous Navigation of Small Solar System Explorers
Pulsar-based Navigation
Ray et al., 2006
Optical Solar Interferometry
Celestial Navigation
5th Interplanetary CubeSat Workshop, Oxford, UK, 24-25 May, 2016
Alternatives – Absolute Navigation Alternatives for Autonomous Navigation of Small Solar System Explorers
Optical Solar Interferometry
CCD detector Sun entrance
Star-light entrance
Attenuator
Coupled Sun Star Tracker
LOS Velocity Signal Frequency Doppler Shift fD
1 mm/s 8x109 Hz (radio) 0.027 Hz
1 mm/s 5x1014 Hz (visible) 1667 Hz
• Modes: – Sun imager – Sun line-of-sight – Conventional imaging system
(Wide-angle camera)
𝑓𝐷𝐷𝐷𝐷𝐷𝐷𝐷 = 𝑓𝑣𝑐
Resonance Scattering Interferometer
Helioseismic and magnetic Imager (HMI) aboard the Solar Dynamics Observatory. Scherrer, 2005
σ = 0.026 rad σ = 1 cm/s
5th Interplanetary CubeSat Workshop, Oxford, UK, 24-25 May, 2016
Alternatives – Absolute Navigation Alternatives for Autonomous Navigation of Small Solar System Explorers
Optical Solar Interferometry + Celestial Navigation
Cruise Nav.
EKF Particle Filter
�̅�𝑠𝑠 , �̅�𝑠𝑠
Resonance Scattering Interferometer
Coupled Sun Star Tracker
WA Camera
�̅�𝐷𝑟𝑟𝑟𝑟𝐷
𝑙�̅�𝑠𝑠
𝑙�̅�𝐷𝑟𝑏
5th Interplanetary CubeSat Workshop, Oxford, UK, 24-25 May, 2016
Alternatives – Absolute Navigation Alternatives for Autonomous Navigation of Small Solar System Explorers
Optical Solar Interferometry + Celestial Navigation
3σ after 5 yrs UKF PF
15 m
in
𝑂 𝒓� km 126.7 39.0
𝑂 𝒓�̇ km/s 151.1 53.6
24 h
r 𝑂 𝒓� km 207.3 167.9
𝑂 𝒓�̇ km/s 39.3 57.4
5th Interplanetary CubeSat Workshop, Oxford, UK, 24-25 May, 2016
Alternatives – Absolute Navigation Alternatives for Autonomous Navigation of Small Solar System Explorers
Pulsar-based Navigation
NICER X-ray Timing Instrument Source: NASA
3D Position error < 5km with simultaneous observation of 3 pulsars following ROSETTA trajectory (Simulations) Bernhardt, M. G. Bad Honnef ,2015
5th Interplanetary CubeSat Workshop, Oxford, UK, 24-25 May, 2016
Alternatives – Relative Navigation Alternatives for Autonomous Navigation of Small Solar System Explorers
Relative Navigation
5th Interplanetary CubeSat Workshop, Oxford, UK, 24-25 May, 2016
Alternatives – Relative Navigation Alternatives for Autonomous Navigation of Small Solar System Explorers
Surface landmark tracking
Global model matching
Shape Model
Simultaneous Localization and Mapping
Visual Odometry
• Optical Camera • Imaging LiDAR
5th Interplanetary CubeSat Workshop, Oxford, UK, 24-25 May, 2016
Alternatives – Relative Navigation Alternatives for Autonomous Navigation of Small Solar System Explorers
LIDAR Point Cloud Matching
Image: Courtesy of H. Gómez (ISTA)
Light Curves
Source: Dr. T.M.Ho (DLR-Planetenforschung)
Asteroid 2008 TC3
Image Matching – Bundle adjustment
Images: Courtesy of R. Jacob (ISTA)
Navigation side-product: Object state estimation
5th Interplanetary CubeSat Workshop, Oxford, UK, 24-25 May, 2016
Alternatives – Relative Navigation Alternatives for Autonomous Navigation of Small Solar System Explorers
Grid-information maps
• Hazards • Fuel • Landing sites • Terrain slope
Shape reconstruction
Navigation side-product: Target modelling
5th Interplanetary CubeSat Workshop, Oxford, UK, 24-25 May, 2016
Evaluation of Alternatives Alternatives for Autonomous Navigation of Small Solar System Explorers
Criteria Ground-based Radio
Optical Solar Interfer.
Optical Celestial Nav.
Pulsar-based Nav.
Optical Odometry
with Cameras
Optical Odometry with LiDAR
On-board autonomy No Yes Yes Yes Yes Yes
TRL 9 3-4 5-6 5-6 7-8 5-6
Navigation accuracy 10-100 km 300 km 100 - 1000 km 5 – 100 km 100 km - 1 m 1m – 10cm
SoA Power demands 1 kW 100 W 10 - 15 W 15 W 10 – 15 W 5 – 10 kg
SoA Mass demands 10 kg 50 kg 5 – 10 kg 10 – 15 kg 5 – 10 kg 30 – 40 W
Illumination dependant
No Yes Yes No Yes No
Scale Invariant No No No Yes No Yes
Spatial range > 15 AU 4-5 AU 2-3 AU Solar system
< 1000 km < 2-5 km
Development costs
Sensor/Payload reusability
Radio Comm., Radio Science
Sun attitude Imaging, Astronomy
X-ray or Radio
astronomy
Mapping Opt. Comm. Terminal and
Mapping
System complexity Low High Medium High Medium Medium
Other requirements - Thermal Thermal Timing , Thermal, Long
obs.
Thermal Pointing
Alternatives for Autonomous Navigation of Small Solar System Explorers
G. González Peytaví, A. Probst, T.P. Andert, B. Eissfeller, R. Förstner
5th Interplanetary CubeSat Workshop, Oxford, UK, 24-25 May 2016