Abstract
Sandy beaches can be smooth access points for future amphibious robots to enter and exit the water, but the terrain is challenging, especially for smaller scale robots. Strong hydrodynamic forces can interrupt navigation by displacing, reorienting, or even inverting the robot. Looking to animals that navigate these conditions, crabs have legs and gaits that are distinctive from land animals and robots. In order to better understand the potential advantages of crab-like legs for surf-zone terrain, our goal is to evaluate these legs on dry, wet, and submerged sandy terrain. With our modified 1.2 kg HEXY robot, we demonstrate two important advantages of crab-like legs. First, crab-like legs can allow the robot to resist vertical forces greater than the body weight (the maximum force required to lift the robot is 120% of the weight). This is important because, in contrast to robots that increase traction by adding weight, using the legs to effectively increase normal forces means that robots can be built lighter and smaller while still traversing the same environments. Secondly, we show distributed inward gripping with the crab-like legs reduce wave-induced displacement in lab tests (with default feet, waves displace the robot 1–4 cm, but with our crab-like feet, this displacement is eliminated). The modified foot designs of the robot are compatible with legged walking gaits (slow, medium, and fast). In the future, these leg designs and grasping strategies can be used to convert other land-based robots for amphibious locomotion.
This is a preview of subscription content, log in via an institution to check access.
Access this chapter
Tax calculation will be finalised at checkout
Purchases are for personal use only
References
Li, C., Umbanhowar, P., Komsuoglu, H., Koditschek, D., Goldman, D.: Sensitive dependence of the motion of a legged robot on granular media. PNAS 106, 3029–3034 (2009)
Sun, Y., Ma, S.: A versatile locomotion mechanism for amphibious robots: eccentric paddle mechanism. In: Advanced Robotics (2013)
J8 Atlas Xtreme Terrain Robot (XTR), Canada. http://www.army-technology.com/projects/j8-atlas-xtreme-terrain-robot-xtr/
Liang, C., Ceccarelli, M., Carbone, G.: Design and simulation of legged walking robots in MATLAB® environment. In: Perutka, K. (ed.) MATLAB for Engineers - Applications in Control, Electrical Engineering, IT and Robotics (2011). ISBN 978-953-307-914-1
Marvi, H., et al.: Sidewinding with minimal slip: snake and robot ascent of sandy slopes. Science 346(6206), 224–229 (2014)
Kim, T.H., Nam, J.M., Yun, J.M., Lee, K.I., You, S.K.: Relationship between cohesion and tensile strength in wet sand and at low normal stresses. In: Proceedings of International Conference on Soil Mechanics and Geotechnical Engineering, pp. 364–367 (2009)
Askari, H., Kamrin, K.: Intrusion in heterogeneous materials: simple global rules from complex micro-mechanics. arXiv preprint arXiv:1510.02966 (2015)
Full, R.J.: Using biological inspiration to build artificial life that locomotes. In: Gomi, T. (ed.) EvoRobots 2001. LNCS, vol. 2217, pp. 110–120. Springer, Heidelberg (2001). https://doi.org/10.1007/3-540-45502-7_6
Boxerbaum, A.S., Werk, P., Quinn, R.D., Vaidyanathan, R.: Design of an autonomous amphibious robot for surf zone operation: Part I mechanical design for multi-mode mobility. In: Proceedings of 2005 IEEE/ASME International Conference on Advanced Intelligent Mechatronics, pp. 1459–1464. IEEE (2005)
Harkins, R., Ward, J., Vaidyanathan, R., Boxerbaum, A.X., Quinn, R.D.: Design of an autonomous amphibious robot for surf zone operations: Part II-hardware, control implementation and simulation. In: Proceedings of 2005 IEEE/ASME International Conference on Advanced Intelligent Mechatronics, pp. 1465–1470. IEEE (2005)
Han, B., et al.: Mechanism design and gait experiment of an amphibian robotic turtle. Adv. Robot. 25(16), 2083–2097 (2011)
SeaOtter. http://www.weeprojects.com/c-2-innovations-inc-c-2i.html
Kelasidi, E., et al.: Innovation in underwater robots: biologically inspired swimming snake robots. IEEE Robot. Autom. Mag. 23(1), 44–62 (2016)
Kelasidi, E., et al.: Locomotion efficiency optimization of biologically inspired snake robots. Appl. Sci. 8(1), 80 (2018)
Nirody, J.A., et al.: Geckos race across the water’s surface using multiple mechanisms. Curr. Biol. 28(24), 4046–4051 (2018)
Kashem, S.B.A., Mujahid, T., Malcolm, C.: A novel design of an amphibious robot having webbed feet as duck. In: International Conference on Computer and Drone Applications (IConDA). IEEE (2017)
Chen, Y., et al.: A biologically inspired, flapping-wing, hybrid aerial-aquatic microrobot. Sci. Robot. 2(11), eaao5619 (2017)
Weis, J.S.: Walking Sideways: The Remarkable World of Crabs. Cornell University Press, Ithaca (2012). ISBN 978-0-8014-5050-1. OCLC 794640315
Martinez, M.M., Full, R.J., Koehl, M.A.: Underwater punting by an intertidal crab: a novel gait revealed by the kinematics of pedestrian locomotion in air versus water. J. Exp. Biol. 201(18), 2609–2623 (1998)
Cunningham, C.W., Blackstone, N.W., Buss, L.W.: Evolution of king crabs from hermit crab ancestors. Nature 355(6360), 539 (1992)
Herreid, C.F., Full, R.J.: Locomotion of hermit crabs (Coenobita compressus) on beach and treadmill. J. Exp. Biol. 120(1), 283–296 (1986)
Martinez, M.M.: Running in the surf: hydrodynamics of the shore crab Grapsus tenuicrustatus. J. Exp. Biol. 204(17), 3097–3112 (2001)
Nguyen, D.N., et al.: Multi-objective optimization design for a sand crab-inspired compliant microgripper. Microsyst. Technol. 1–19 (2019)
Ayers, J., Witting, J.: Biomimetic approaches to the control of underwater walking machines. Philos. Trans. R. Soc. Lond. A Math. Phys. Eng. Sci. 365(1850), 273–295 (2007)
Krummel, G., Kaipa, K.N., Gupta, S.K.: A horseshoe crab inspired surf zone robot with righting capabilities. In: ASME 2014 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference, p. V05AT08A010. American Society of Mechanical Engineers, August 2014
Falconer, J.: Huge Six-Legged Robot Crabster Goes Swimming. IEEE Spectrum, 30 July 2013. https://spectrum.ieee.org/automaton/robotics/industrial-robots/six-legged-underwater-robot-crabster
Elsley, D.R., et al.: Autonomous legged underwater vehicles for near land warfare. In: Proceedings of the Autonomous Vehicles in Mine Countermeasures Symposium, Naval Postgraduate School, 4–7 April 1995
Wile, G.D., et al.: Screenbot: walking inverted using distributed inward gripping. In: IEEE/RSJ International Conference on Intelligent Robots and Systems, IROS 2008, pp. 1513–1518. IEEE, September 2008
Hawkes, E.W., et al.: Dynamic surface grasping with directional adhesion. In: IEEE/RSJ International Conference on Intelligent Robots and Systems, pp. 5487–5493. IEEE, November 2013
Palmer III, L.R., Diller, E., Quinn, R.D.: Toward gravity-independent climbing using a biologically inspired distributed inward gripping strategy. IEEE/ASME Trans. Mechatron. 20(2), 631–640 (2015)
Acknowledgment
We would like to thank Ariel Foss for help with data entry, Noah Napiewocki and Justin Wong for constructing the wave tank, and Chenming Wei for helping make the drawings of the feet. This work was sponsored by the Office of Naval Research and CWRU Graduate Student Travel Award.
Author information
Authors and Affiliations
Corresponding author
Editor information
Editors and Affiliations
Rights and permissions
Copyright information
© 2019 Springer Nature Switzerland AG
About this paper
Cite this paper
Graf, N.M., Behr, A.M., Daltorio, K.A. (2019). Crab-Like Hexapod Feet for Amphibious Walking in Sand and Waves. In: Martinez-Hernandez, U., et al. Biomimetic and Biohybrid Systems. Living Machines 2019. Lecture Notes in Computer Science(), vol 11556. Springer, Cham. https://doi.org/10.1007/978-3-030-24741-6_14
Download citation
DOI: https://doi.org/10.1007/978-3-030-24741-6_14
Published:
Publisher Name: Springer, Cham
Print ISBN: 978-3-030-24740-9
Online ISBN: 978-3-030-24741-6
eBook Packages: Computer ScienceComputer Science (R0)