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Integrated Sensing Systems for Asteroid Missions Asteroid Initiative Idea Synthesis Workshop Sept 30, 2013 Rich Dissly and Kevin Miller Ball Aerospace & Technologies Corp. Scope of Presentation. Use a notional mission scenario for asteroid capture to assess: What on-board sensors are needed?
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Integrated Sensing Systems for Asteroid MissionsAsteroid Initiative Idea Synthesis WorkshopSept 30, 2013Rich Dissly and Kevin MillerBall Aerospace & Technologies Corp.
Scope of Presentation Use a notional mission scenario for asteroid capture to assess: • What on-board sensors are needed? • Conclusion: Minimum suite includes narrow and wide FOV visible imagers, imaging LIDAR • What sensors are available? • Are there gaps? • Conclusion: Mature sensors exist. Gap in fully autonomous software for prox ops • Applicable to other recon missions to small bodies, AR&D, orbital debris remediation, satellite servicing Dissly – Integrated Sensing Systems for Asteroid Missions
What are Sensor Requirements for ARM? 4 Dist: <2km Nav Needs: Range, bearing Refine: Surface features Sensors: NFOV Vis Imager, Imaging LIDAR Dist: <10km Nav Needs: Range, bearing Refine: Shape, spin, surface Sensors: NFOV Vis Imager, LIDAR 3 Dist: 10-1000km Nav Need: Bearing Refine: Shape, spin Sensor: NFOV Vis Imager 2 Dist: 10-100m Nav Needs: Range, bearing, pose Refine: Surface features Sensors: Wide FOV Vis Imager, Imaging LIDAR 5 6 Dist: 0m Nav Needs: Range, bearing, pose Sensors: Wide FOV Vis Imagers, Imaging LIDAR, Contact sensors 1 Dist: 10^5 km Nav Need: Bearing Sensor: Narrow FOV Vis Imager Missing: Recon of Target Mechanical Properties Dissly – Integrated Sensing Systems for Asteroid Missions
Candidate Sensor: Flash Lidar • Successful demo of Vision Navigation Sensor on STS-134 (STORRM) • Radiometric performance can be made compatible with low albedo targets (asteroids) • Can enhance with adaptive beam steering (responsive to target parameters, geometry) Visible Image VNS Intensity Image VNS Range Image Dissly – Integrated Sensing Systems for Asteroid Missions
Technology Gap: Robust Real-Time, Fully Autonomous Proximity Operations • Example data: Fusion of visible image with LIDAR provides natural feature pose determination and hazard identification under all lighting conditions • This needs to be provided in REAL-TIME to spacecraft GNC system • Natural targets pose unique problems; e.g., how do you detect edges of an asteroid? • Has been partially demonstrated on the ground for semi-cooperative or non-cooperative targets (e.g., SOSC testing) • Autonomous closed-loop TRN/Haz Avoidance – will be demonstrated on Morpheus soon Visible LIDAR SOSC Asteroid Wall Fused Overlay Morpheus Landing Test Dissly – Integrated Sensing Systems for Asteroid Missions
Architectural Enhancements to Reduce Mission Risk • Need to assess target strength prior to capture attempt • Rubble pile? Monolith? • This affects capture operations • Likely requires touching surface Options: • Surface probe • Viable for 100m+ objects • Small explosive charge to assess target strength • Small free flyer • Includes contact probe for touch-and-go surface measurement • Provides unique vantage point for imaging capture sequence Asteroid Surface Probe Dissly – Integrated Sensing Systems for Asteroid Missions
Conclusions • ARM sensing requirements include (i) Range, (ii) Pose estimation for a resolved target, and (iii) High-resolution visible imaging correlated to pose estimation • These measurements need to be made autonomously and in real-time • Mature sensors exist for making these measurements • Software and testing for fully autonomous proximity operations needs additional development • Separate flight elements to contact/perturb the target surface can reduce mission risk Dissly – Integrated Sensing Systems for Asteroid Missions