Below are the topics of the GNC 2021 edition.

Advances in Sensors and Actuators 
Papers are encouraged to describe new hardware developments and promising new technologies. Papers may cover component developments, equipment developments and new test results. Papers are also encouraged on requirement evolution and trends. This session will cover all types of sensors used in GNC, such as gyroscopes, accelerometers, inertial measurement units, high bandwidth angular rate sensors, star trackers, Sun sensors, Earth sensors, magnetometers, navigation cameras (visible, IR, multi-spectral, 3D), as well as actuators, magnetic torquers & reaction wheels.

Advances in Controls 
The session contemplates advanced control technologies driven by demanding and complex space missions. Papers should focus on demonstrating how advanced techniques (such as advanced modelling, analysis, control, and optimization techniques) can be used for given applications and quantifying their benefits at system level in terms of performance and stability margins, GNC design, development, validation and verification process. This session covers as well simultaneous co-design between GNC and other disciplines (propulsion, aerodynamics, structures). 

Current Space Missions 
The Current Space Missions session presents the GNC detailed design aiming at answering the mission’s key requirements and challenges. Current missions are those presently in Phases B, C or D. Papers should highlight especially for  innovative GNC concepts, architectures design, describing challenging trade-offs and criticalities.

Future Space Missions
The Future Space Missions session presents the GNC preliminary design, and their key requirements and challenges, together with how these have been addressed. This session targets pre-Phase A or Phase A missions. Papers are encouraged especially to address missions with innovative GNC designs driven by challenging demands and requirements.

In-Orbit Experiences and Demonstrators 
This session presents the results of in-orbit experiences of GNC systems and hardware. Emphasis is placed on in flight performance validation and demonstration of new techniques as well as anomaly description, recovery and work-arounds. The session also covers experience and lessons learnt from  field tests. The session also addresses the development, design and verification of novel demonstrator capabilities at all phases of development.

GNC for Future Space Transportation Systems
This session addresses the challenges of GNC design and development for space transportation that includes launch, orbital, and re-entry descent & landing vehicles. This session covers GNC design, development, testing and operations for any space vehicle devoted to space transportation (including the case of manned missions). We encourage papers in the field of micro-launchers or reusable launchers.

GNC for Planetary Exploration
This session explores the specific challenges and hardware requirements needed for interplanetary exploration missions. This session focuses on GNC systems for the exploration of the Moon and planetary missions.  The session covers also autonomous orbit insertion, aerobraking, and entry descent and landing, with a particular emphasis on the GNC chain validation strategies through prototyping, bread boarding, real time testing, and dynamics testing through ground-based or flying testbeds.

GNC for Small Body Missions
This session focuses on the specific challenges of GNC systems for missions to small celestial bodies, including autonomous and semi-autonomous relative navigation strategies, close proximity operations definition and planning, and GNC architectures, algorithms and hardware design, development, verification and validation to support close proximity operations. Specific challenges on the GNC system posed by small-body landing missions are also addressed.

GNC for In Orbit Robotic Operations
This session addresses the new challenges arising from the need of performing in-orbit robotic operations such as servicing, assembly, and active debris removal, from a GNC perspective. Core topic of this session is the spacecraft and spacecraft composites stabilization during proximity operations near the target object when robotic arms are used for target manipulation. Additional topics cover the design, development, and verification of GNC systems in support to target de-tumbling, non-cooperative rendezvous, image processing and navigation.

High Performance Pointing Systems
This session is focused on high accuracy and high stability pointing systems (in the range of the arc seconds or below) typically needed for emerging science missions or high resolution imaging satellites. The session will in particular address pointing error engineering, active disturbance isolation, line of sight stabilization, calibration, filtering and control techniques and AOCS architectural design with sensors and actuators to cope with a very high pointing requirements.

Autonomy, Fault Tolerant Control and Operations
FDIR engineering aims to cover unintended behaviours that may affect the system, and being the number of unintended behaviour potentially infinite it might lead to increasing system complexity. The FDIR concept shall cope with constraints on the system autonomy needs, mission availability requirements and operations possibly leading to costly verification and validation challenges. This session will report about harmonization of FDIR process, health monitoring and technologies to implement solutions with particular focus on efficiency in the system development process, not only during system verification and validation, but also in the early phases of the mission design. The session welcomes also presentations about trade off between on board autonomy and ground control operations related to FDIR and mission specific constraints addressing all unmanned missions (Earth Observation in LEO or GEO, telecommunication satellites and interplanetary missions with very long ground reaction times). 

Sensors Data Fusion and Autonomous Navigation
This session is devoted to autonomous navigation from conceptual design to hardware implementation, and testing. The list of topics covered includes: autonomous orbit determination (based in particular on GNSS systems in Earth orbits), autonomous vision-based, infrared, and multi-spectral navigation, covering planetary landing (absolute and relative navigation), interplanetary navigation (e.g. encounter with small bodies or planetary swing-by optimization), rendezvous navigation,  hybrid navigation techniques and multi-sensors data fusion tailored to space missions, and associated avionics implementation solutions. Beyond describing the techniques themselves, the papers should demonstrate their benefits at system level.

Challenges of LEO missions
This session will analyze the main challenges of AOCS for LEO satellites, mostly focusing on the new generation of LEO platforms for Earth Observation (e.g. Copernicus programme) and the (foreseen) constellations of satellites to be launched in LEO orbit, to increase coverage for services and shorter revisit time for operational missions. In particular, the session will discuss about the optimization and innovation of the AOCS design and process of the most recent LEO platforms. The changes/optimization in V&V process for large scale productions at unit hardware and AOCS/system level verification. In addition, papers are encouraged to discuss the compliance with debris mitigation guidelines, the challenges of implementing (autonomous) collision avoidance in flight and safe controlled re-entry.

Trends in AI for GNC Systems
Recent advances in Artificial Intelligence (AI) and specifically in Machine Learning have the potential to complement and augment the GNC system architectures with new techniques for modelling and system identification, filtering, and control. In addition, an enhancement of on-board autonomy can be envisaged through AI techniques. This session discusses the current trends in the integration of AI within GNC systems, applied to tasks such as spacecraft stabilization and control, image processing (e.g. feature recognition and tracking), failure diagnostics and prognostics, health monitoring and management systems, etc. In addition, papers are encouraged to discuss how AI can be employed to augment the traditional design and verification process of GNC systems.