Proprietary of Rafael – Advanced Defense Systems Ltd 1 Ilan Ramon 2016 TILDOCS# UNCLASSIFIED Ofer Salama RAFAEL small satellite constellations - Benefits & Constraints Benefits & Constraints

Proprietary of Rafael – Advanced Defense Systems Ltd 2 Ilan Ramon 2016 TILDOCS# UNCLASSIFIED Rafael’s small satellite constellations: LiteSat: microsatellite for Electro-Optic Earth Observation NanREC: nanosatellite for Communication Relay NanREC: nanosatellite for Communication Relay

Proprietary of Rafael – Advanced Defense Systems Ltd 3 Ilan Ramon 2016 TILDOCS# UNCLASSIFIED “Affordable”: low cost & high performance satellites High “operational effectiveness”/ cost (including launch – one launch to each orbit) “Operational effectiveness“: High operational performance (with updated technology) No Single Critical Failure (satellite level) Programmatic ORS capabilities (including Time to Market) Affordable Constellations – The Benefits

Proprietary of Rafael – Advanced Defense Systems Ltd 4 Ilan Ramon 2016 TILDOCS# UNCLASSIFIED LiteSat Imaging Resolution – 60 cm

Proprietary of Rafael – Advanced Defense Systems Ltd 5 Ilan Ramon 2016 TILDOCS# UNCLASSIFIED Accesses per Day Imaging - Constellation Capability

Proprietary of Rafael – Advanced Defense Systems Ltd 6 Ilan Ramon 2016 TILDOCS# UNCLASSIFIED LiteSat Satellite

Proprietary of Rafael – Advanced Defense Systems Ltd 7 Ilan Ramon 2016 TILDOCS# UNCLASSIFIED LiteSat Main Characteristics

Proprietary of Rafael – Advanced Defense Systems Ltd 8 Ilan Ramon 2016 TILDOCS# UNCLASSIFIED Image Products Exploitation Tools Change detection & Historical intelligence investigation Mosaics of images Stereo images Orientation Mapping Products Orthophoto DTM DSM 3D images Self generated GCP The products shown in RED require several frequent images (Revisit) of the same target

Proprietary of Rafael – Advanced Defense Systems Ltd 9 Ilan Ramon 2016 TILDOCS# UNCLASSIFIED Design Considerations

Proprietary of Rafael – Advanced Defense Systems Ltd 10 Ilan Ramon 2016 TILDOCS# UNCLASSIFIED Satellites with high attitude requirements usually use several STR’s LiteSat Elongated shape and limited size impose the use of a single STR and yet comply to mission accuracies, lifespan and reliability Single STR Design (1)

Proprietary of Rafael – Advanced Defense Systems Ltd 11 Ilan Ramon 2016 TILDOCS# UNCLASSIFIED The use of a single STR emphasize the following design constraints: Reliability: how can we guaranty for the systems reliability and NSPF with a single STR STR blinding which is commonly handled with several STRs, should be handled by other means Single STR Design (2)

Proprietary of Rafael – Advanced Defense Systems Ltd 12 Ilan Ramon 2016 TILDOCS# UNCLASSIFIED The STR is clearly a single point failure and therefore non HW ‘redundancy’ was implemented in the design: In case the STR fails, an accurate gyro is still available onboard and the camera is used as an additional STR The camera is pointed to known stars and the attitude sensors are compared to the reference attitude given by the stars The ‘Stars Imaging Process’ should be performed periodically and can degrade the image capacity Reliability and NSPF

Proprietary of Rafael – Advanced Defense Systems Ltd 13 Ilan Ramon 2016 TILDOCS# UNCLASSIFIED Stars Imaging Process (1) FK5 Star catalogue FK6 Star catalogue

Proprietary of Rafael – Advanced Defense Systems Ltd 14 Ilan Ramon 2016 TILDOCS# UNCLASSIFIED Stars Imaging Process (2) Angular separation

Proprietary of Rafael – Advanced Defense Systems Ltd 15 Ilan Ramon 2016 TILDOCS# UNCLASSIFIED Single STR Blinding Avoidance (1) In case the satellite is required to point the STR in the vicinity of the sun while maneuvering between image acquisitions, an onboard algorithm plans an attitude trajectory to avoid STR blinding.

Proprietary of Rafael – Advanced Defense Systems Ltd 16 Ilan Ramon 2016 TILDOCS# UNCLASSIFIED Since the algorithm is capable of handling any attitude constraint (not only STR blinding), all mission attitude constraints were included. Attitude constraints include: Single STR Blinding Avoidance (2) Consequence of ViolationAttitude Constraint# Loss of tracking abilityMinimal angle between the STR and the Sun1 Loss of tracking abilityMinimal angle between the STR and the Earth Disc2 Temporal damage to the cameraMinimal angle between the camera and the sun3 Permanent degradation of the cameraMinimal angle between the camera and the ATOX4

Proprietary of Rafael – Advanced Defense Systems Ltd 17 Ilan Ramon 2016 TILDOCS# UNCLASSIFIED Attitude Constraints Avoidance Animation (1) Play Movie

Proprietary of Rafael – Advanced Defense Systems Ltd 18 Ilan Ramon 2016 TILDOCS# UNCLASSIFIED Attitude Constraints Avoidance Animation (2) Play Movie

Proprietary of Rafael – Advanced Defense Systems Ltd 19 Ilan Ramon 2016 TILDOCS# UNCLASSIFIEDConclusion Affordable high performance constellation requires innovative solutions An example is demonstrated - LiteSat design incorporating structural and attitude constraints: Despite the fact that LiteSat is using a single STR, the hardware is ‘redundant’ by other means and processes onboard A novel attitude constraints avoidance algorithm is implemented onboard.

Proprietary of Rafael – Advanced Defense Systems Ltd 20 Ilan Ramon 2016 TILDOCS# UNCLASSIFIED Thank You