An insect-inspired bionic sensor for tactile localization and material classification with state-dependent modulation

Insects carry a pair of antennae on their head: multimodal sensory organs that serve a wide range of sensory-guided behaviors. During locomotion, antennae are involved in near-range orientation, for example in detecting, localizing, probing, and negotiating obstacles. Here we present a bionic, active tactile sensing system inspired by insect antennae. It comprises an actuated elastic rod equipped with a terminal acceleration sensor. The measurement principle is based on the analysis of damped harmonic oscillations registered upon contact with an object. The dominant frequency of the oscillation is extracted to determine the distance of the contact point along the probe and basal angular encoders allow tactile localization in a polar coordinate system. Finally, the damping behavior of the registered signal is exploited to determine the most likely material. The tactile sensor is tested in four approaches with increasing neural plausibility: first, we show that peak extraction from the Fourier spectrum is sufficient for tactile localization with position errors below 1%. Also, the damping property of the extracted frequency is used for material classification. Second, we show that the Fourier spectrum can be analysed by an Artificial Neural Network (ANN) which can be trained to decode contact distance and to classify contact materials. Thirdly, we show how efficiency can be improved by band-pass filtering the Fourier spectrum by application of non-negative matrix factorization. This reduces the input dimension by 95% while reducing classification performance by 8% only. Finally, we replace the FFT by an array of spiking neurons with gradually differing resonance properties, such that their spike rate is a function of the input frequency. We show that this network can be applied to detect tactile contact events of a wheeled robot, and how detrimental effects of robot velocity on antennal dynamics can be suppressed by state-dependent modulation of the input signals.

[1]  Eugene M. Izhikevich,et al.  Resonate-and-fire neurons , 2001, Neural Networks.

[2]  Florentin Wörgötter,et al.  Efference copies in neural control of dynamic biped walking , 2009, Robotics Auton. Syst..

[3]  Makoto Kaneko,et al.  Dynamic contact sensing by flexible beam , 1998 .

[4]  Oliver Dr. Lange,et al.  Vorrichtung und Verfahren zur Erfassung von Hindernissen , 2005 .

[5]  Ralf Möller,et al.  Passive sensing and active sensing of a biomimetic whisker , 2006 .

[6]  Volker Dürr,et al.  Insectoid obstacle detection based on an active tactile approach , 2005 .

[7]  Bruno A Olshausen,et al.  Sparse coding of sensory inputs , 2004, Current Opinion in Neurobiology.

[8]  W. Stein,et al.  Physiology of vibration-sensitive afferents in the femoral chordotonal organ of the stick insect , 1999, Journal of Comparative Physiology A.

[9]  Frank C. Hoppensteadt,et al.  Bursts as a unit of neural information: selective communication via resonance , 2003, Trends in Neurosciences.

[10]  Eugene M. Izhikevich,et al.  Simple model of spiking neurons , 2003, IEEE Trans. Neural Networks.

[11]  V. Dürr,et al.  Biomechanics of the stick insect antenna: damping properties and structural correlates of the cuticle. , 2011, Journal of the mechanical behavior of biomedical materials.

[12]  Amir Karniel,et al.  Three creatures named 'forward model' , 2002, Neural Networks.

[13]  J. Poulet,et al.  New insights into corollary discharges mediated by identified neural pathways , 2007, Trends in Neurosciences.

[14]  Joseph H. Solomon,et al.  Biomechanics: Robotic whiskers used to sense features , 2006, Nature.

[15]  V. Dürr,et al.  Antennal movements and mechanoreception: neurobiology of active tactile sensors , 2005 .

[16]  Ruggero Petacchi,et al.  Ultrastructural characterization of antennal sensilla and immunocytochemical localization of a chemosensory protein in Carausius morosus Brünner (Phasmida: Phasmatidae). , 2002, Arthropod structure & development.

[17]  T. Prescott,et al.  Active vibrissal sensing in rodents and marsupials , 2011, Philosophical Transactions of the Royal Society B: Biological Sciences.

[18]  Volker Dürr,et al.  Helping a Bio-inspired Tactile Sensor System to Focus on the Essential , 2011, ICIRA.

[19]  B. Webb.  Neural mechanisms for prediction: do insects have forward models? , 2004, Trends in Neurosciences.

[20]  Noah J. Cowan,et al.  Dynamical Wall Following for a Wheeled Robot Using a Passive Tactile Sensor , 2005, Proceedings of the 2005 IEEE International Conference on Robotics and Automation.

[21]  V. Dürr,et al.  Active tactile exploration for adaptive locomotion in the stick insect , 2011, Philosophical Transactions of the Royal Society B: Biological Sciences.

[22]  Berthold Hedwig,et al.  A corollary discharge maintains auditory sensitivity during sound production , 2002, Nature.

[23]  A. Wing,et al.  Active touch sensing , 2011, Philosophical Transactions of the Royal Society B: Biological Sciences.

[24]  T. Prescott,et al.  Biomimetic vibrissal sensing for robots , 2011, Philosophical Transactions of the Royal Society B: Biological Sciences.

[25]  Holger G Krapp.  Sensory Integration: Neuronal Adaptations for Robust Visual Self-Motion Estimation , 2009, Current Biology.

[26]  M. Sommer,et al.  Corollary discharge across the animal kingdom , 2008, Nature Reviews Neuroscience.

[27]  V. Dürr,et al.  The antennal motor system of the stick insect Carausius morosus: anatomy and antennal movement pattern during walking , 2001, Journal of Comparative Physiology A.

[28]  Holger G. Krapp,et al.  Insect-Inspired Estimation of Egomotion , 2004, Neural Computation.

[29]  Christian Berg,et al.  An insect brain computational model inspired by Drosophila melanogaster: Architecture description , 2010, The 2010 International Joint Conference on Neural Networks (IJCNN).

[30]  Stefan Schaal,et al.  Forward models in visuomotor control. , 2002, Journal of neurophysiology.

[31]  Anthony G. Pipe,et al.  Whiskerbot: A Robotic Active Touch System Modeled on the Rat Whisker Sensory System , 2007, Adapt. Behav..

[32]  Florentin Wörgötter,et al.  Using efference copy and a forward internal model for adaptive biped walking , 2010, Auton. Robots.

[33]  André Frank Krause,et al.  Bionic Tactile Sensor for Near-Range Search, Localisation and Material Classification , 2007, AMS.

[34]  Cristina Savin,et al.  Resonance or integration? Self-sustained dynamics and excitability of neural microcircuits. , 2007, Journal of neurophysiology.

[35]  M. Gebhardt,et al.  Physiological characterisation of antennal mechanosensory descending interneurons in an insect (Gryllus bimaculatus, Gryllus campestris) brain. , 2001, The Journal of experimental biology.

[36]  Paolo Arena,et al.  A spiking network for object and ego-motion detection in roving robots , 2012, The 2012 International Joint Conference on Neural Networks (IJCNN).

[37]  E. Staudacher,et al.  Gating of sensory responses of descending brain neurones during walking in crickets , 1998 .

[38]  Roger D. Quinn,et al.  Insect-like Antennal Sensing for Climbing and Tunneling Behavior in a Biologically-inspired Mobile Robot , 2005, Proceedings of the 2005 IEEE International Conference on Robotics and Automation.

[39]  R. F. MARK,et al.  Corollary Discharge? , 1968, Nature.

[40]  Jan Wessnitzer,et al.  Resonant neurons and bushcricket behaviour , 2007, Journal of Comparative Physiology A.

[41]  Noah J. Cowan,et al.  A tunable physical model of arthropod antennae , 2010, 2010 IEEE International Conference on Robotics and Automation.

[42]  Luigi Fortuna,et al.  Integrating high-level sensor features via STDP for bio-inspired navigation , 2007, 2007 IEEE International Symposium on Circuits and Systems.

[43]  Toshio Tsuji,et al.  Active antenna for contact sensing , 1998, IEEE Trans. Robotics Autom..

[44]  Janette Atkinson,et al.  Channels in Vision: Basic Aspects , 1978 .

[45]  Robert J. Full,et al.  Templates and Anchors for Antenna-Based Wall Following in Cockroaches and Robots , 2008, IEEE Transactions on Robotics.

[46]  Larry S. Davis,et al.  Human detection using partial least squares analysis , 2009, 2009 IEEE 12th International Conference on Computer Vision.

[47]  André Frank Krause,et al.  Feel Like an Insect: A Bio-Inspired Tactile Sensor System , 2010, ICONIP.

[48]  P. Arena,et al.  STDP-based behavior learning on the TriBot robot , 2009, Microtechnologies.

[49]  Xiao-Jing Wang,et al.  Persistent neural activity: experiments and theory. , 2003, Cerebral cortex.

[50]  Helge J. Ritter,et al.  Neural computation and self-organizing maps - an introduction , 1992, Computation and neural systems series.

[51]  H. Sebastian Seung,et al.  Learning the parts of objects by non-negative matrix factorization , 1999, Nature.

[52]  D. Kleinfeld,et al.  'Where' and 'what' in the whisker sensorimotor system , 2008, Nature Reviews Neuroscience.

[53]  Volker Dürr,et al.  Functional grouping of descending interneurons that mediate antennal mechanosensory information to motor networks , 2009 .

[54]  P. Arena,et al.  A cricket-inspired Neural Network For FeedForward Compensation and Multisensory Integration , 2005, Proceedings of the 44th IEEE Conference on Decision and Control.

[55]  Luigi Fortuna,et al.  A bio-inspired auditory perception model for amplitude-frequency clustering (keynote Paper) , 2005, SPIE Microtechnologies.

[56]  Luigi Fortuna,et al.  Reactive navigation through multiscroll systems: from theory to real-time implementation , 2008, Auton. Robots.

[57]  Takeshi Tsujimura,et al.  A tactile sensing method for employing force/torque information through insensitive probes , 1992, Proceedings 1992 IEEE International Conference on Robotics and Automation.

[58]  Mark R. Cutkosky,et al.  A Biologically Inspired Passive Antenna for Steering Control of a Running Robot , 2003, ISRR.