Identification of cryovolcanism on Titan using fuzzy cognitive maps

Future planetary exploration of Titan will require higher degrees of on-board automation, including autonomous determination of sites where the probability of significant scientific findings is the highest. In this paper, a novel Artificial Intelligence (AI) method for the identification and interpretation of sites that yield the highest potential of cryovolcanic activity is presented. We introduce the theory of fuzzy cognitive maps (FCM) as a tool for the analysis of remotely collected data in planetary exploration. A cognitive model embedded in a fuzzy logic framework is constructed via the synergistic interaction of planetary scientists and AI experts. As an application example, we show how FCM can be employed to solve the challenging problem of recognizing cryovolcanism from Synthetic Aperture Radar (SAR) Cassini data. The fuzzy cognitive map is constructed using what is currently known about cryovolcanism on Titan and relies on geological mapping performed by planetary scientists to interpret different locales as cryovolcanic in nature. The system is not conceived to replace the human scientific interpretation, but to enhance the scientists’ ability to deal with large amounts of data, and it is a first step in designing AI systems that will be able, in the future, to autonomously make decisions in situations where human analysis and interpretation is not readily available or could not be sufficiently timely. The proposed FCM is tested on Cassini radar data to show the effectiveness of the system in reaching conclusions put forward by human experts and published in the literature. Four tests are performed using the Ta SAR image (October 2004 fly-by). Two regions (i.e. Ganesa Macula and the lobate high backscattering region East of Ganesa) are interpreted by the designed FCM as exhibiting cryovolcanism in agreement with the initial interpretation of the regions by Stofan et al. (2006). Importantly, the proposed FCM is shown to be flexible and adaptive as new data and knowledge are acquired during the course of exploration. Subsequently, the FCM has been modified to include topographic information derived from SAR stereo data. With this additional information, the map concludes that Ganesa Macula is not a cryovolcanic region. In conclusion, the FCM methodology is shown to be a critical and powerful component of future autonomous robotic spacecraft (e.g., orbiter(s), balloon(s), surface/lake lander(s), rover(s)) that will be deployed for the exploration of Titan.

[1]  Jeffrey S. Kargel,et al.  The geology of Triton. , 1995 .

[2]  Robert T. Pappalardo,et al.  Formation of Ganymede Grooved Terrain by Sequential Extensional Episodes: Implications of Galileo Observations for Regional Stratigraphy☆ , 1998 .

[3]  Jeffrey S. Kargel,et al.  Intelligent systems for the autonomous exploration of Titan and Enceladus , 2008, SPIE Defense + Commercial Sensing.

[4]  J. Burns,et al.  Cassini Imaging Science: Instrument Characteristics And Anticipated Scientific Investigations At Saturn , 2004 .

[5]  Zhi-Qiang Liu,et al.  On causal inference in fuzzy cognitive maps , 2000, IEEE Trans. Fuzzy Syst..

[6]  John S. Lewis,et al.  Volatile element chemistry in the solar nebula: Na, K, F, Cl, Br, and P , 1980 .

[7]  Roberto Orosei,et al.  Cryovolcanic features on Titan's surface as revealed by the Cassini Titan Radar Mapper , 2007 .

[8]  Gabriel Tobie,et al.  Titan's Hidden Ocean , 2008, Science.

[9]  C. Sotin,et al.  Evolution of Titan and implications for its hydrocarbon cycle , 2009, Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences.

[10]  G. Schubert,et al.  Saturn's icy satellites - Thermal and structural models , 1983 .

[11]  Chrysostomos D. Stylios,et al.  Fuzzy Cognitive Maps in modeling supervisory control systems , 2000, J. Intell. Fuzzy Syst..

[12]  G. Neukum,et al.  Cassini Observes the Active South Pole of Enceladus , 2006, Science.

[13]  Jeffrey S. Kargel,et al.  Rheological properties of ammonia-water liquids and crystal-liquid slurries - Planetological applications , 1991 .

[14]  C. Sotin,et al.  Episodic outgassing as the origin of atmospheric methane on Titan , 2005, Nature.

[15]  Gilberto Espinosa-Paredes,et al.  Emergency management for a nuclear power plant using fuzzy cognitive maps , 2008 .

[16]  C. Sotin,et al.  Analysis of a cryolava flow-like feature on Titan , 2009 .

[17]  Mark A. Tarbell,et al.  Multi-rover testbed for teleconducted and autonomous surveillance, reconnaissance, and exploration , 2009, Defense + Commercial Sensing.

[18]  Bart Kosko,et al.  Fuzzy Cognitive Maps , 1986, Int. J. Man Mach. Stud..

[19]  Mark A. Tarbell,et al.  CYCLOPS: A mobile robotic platform for testing and validating image processing and autonomous navigation algorithms in support of artificial vision prostheses , 2009, Comput. Methods Programs Biomed..

[20]  R. C. Tees.  Review of The organization of behavior: A neuropsychological theory. , 2003 .

[21]  J J Hopfield,et al.  Neural networks and physical systems with emergent collective computational abilities. , 1982, Proceedings of the National Academy of Sciences of the United States of America.

[22]  Charles Elachi,et al.  Titan's Elusive Lakes? Properties and Context of Dark Spots in Cassini TA Radar Data , 2005 .

[23]  E. H. Mamdani,et al.  Application of Fuzzy Logic to Approximate Reasoning Using Linguistic Synthesis , 1976, IEEE Transactions on Computers.

[24]  Bruce Fegley,et al.  Solar nebula chemistry: origins of planetary, satellite and cometary volatiles , 1989 .

[25]  Chrysostomos D. Stylios,et al.  Modeling complex systems using fuzzy cognitive maps , 2004, IEEE Transactions on Systems, Man, and Cybernetics - Part A: Systems and Humans.

[26]  Ralph D. Lorenz,et al.  Pillow lava on Titan: expectations and constraints on cryovolcanic processes , 1996 .

[27]  Roberto Furfaro,et al.  Fuzzy logic expert system for tier-scalable planetary reconnaissance , 2006 .

[28]  Gabriel Tobie,et al.  Titan's internal structure inferred from a coupled thermal-orbital model , 2005 .

[29]  Rosaly M. C. Lopes,et al.  Resurfacing of Titan by ammonia-water cryomagma , 2005 .

[30]  J. Kargel,et al.  Cryovolcanism on the icy satellites , 1994 .

[31]  Jeffrey S. Kargel,et al.  Brine volcanism and the interior structures of asteroids and icy satellites , 1991 .

[32]  Robert T. Pappalardo,et al.  Cryomagmatic Mechanisms for the Formation of Rhadamanthys Linea, Triple Band Margins, and Other Low-Albedo Features on Europa , 2000 .

[33]  Guy J. Consolmagno,et al.  Resurfacing Saturn's satellites: Models of partial differentiation and expansion , 1985 .

[34]  Roberto Furfaro,et al.  Wind-based navigation of a hot-air balloon on Titan: a feasibility study , 2008, SPIE Defense + Commercial Sensing.

[35]  Randolph L. Kirk,et al.  Mapping of Titan: Results from the first Titan radar passes , 2006 .

[36]  Jeffrey S. Kargel,et al.  Neptune and triton , 1997 .

[37]  R. Kirk,et al.  Cassini Radar Views the Surface of Titan , 2005, Science.

[38]  Trent M. Hare,et al.  Topography and geomorphology of the Huygens landing site on Titan , 2007 .

[39]  Olivier Grasset,et al.  The Cooling Rate of a Liquid Shell in Titan's Interior , 1996 .

[40]  Angioletta Coradini,et al.  Photometric changes on Saturn's Titan: Evidence for active cryovolcanism , 2009 .

[41]  F. Attneave,et al.  The Organization of Behavior: A Neuropsychological Theory , 1949 .

[42]  T. Ross.  Fuzzy Logic with Engineering Applications , 1994 .

[43]  J. Moore,et al.  Flooding of Ganymede's bright terrains by low-viscosity water-ice lavas , 2001, Nature.

[44]  R. H. Brown,et al.  The Cassini Visual And Infrared Mapping Spectrometer (Vims) Investigation , 2004 .

[45]  Panagiota Spyridonos,et al.  Brain tumor characterization using the soft computing technique of fuzzy cognitive maps , 2008, Appl. Soft Comput..

[46]  John S. Lewis,et al.  Low temperature condensation from the solar nebula , 1972 .

[47]  Trent M. Hare,et al.  Next-generation robotic planetary reconnaissance missions: A paradigm shift , 2005 .

[48]  D. Schulze-Makuch,et al.  Tier-Scalable Reconnaissance Missions For The Autonomous Exploration Of Planetary Bodies , 2007, 2007 IEEE Aerospace Conference.

[49]  Jeffrey S. Kargel,et al.  Ammonia-water volcanism on icy satellites: Phase relations at 1 atmosphere , 1992 .

[50]  Trent M. Hare,et al.  The search for life beyond Earth through fuzzy expert systems , 2008 .

[51]  Chrysostomos D. Stylios,et al.  Active Hebbian learning algorithm to train fuzzy cognitive maps , 2004, Int. J. Approx. Reason..

[52]  Chrysostomos D. Stylios,et al.  An integrated two-level hierarchical system for decision making in radiation therapy based on fuzzy cognitive maps , 2003, IEEE Transactions on Biomedical Engineering.

[53]  Wolfgang Fink.  Generic Prioritization Framework for Target Selection and Instrument Usage for Reconnaissance Mission Autonomy , 2006, The 2006 IEEE International Joint Conference on Neural Network Proceedings.

[54]  F. Paganelli,et al.  Cassini RADAR images at Hotei Arcus and western Xanadu, Titan: Evidence for geologically recent cryovolcanic activity , 2009 .

[55]  R. Kirk,et al.  Rain, winds and haze during the Huygens probe's descent to Titan's surface , 2005, Nature.