Editing Robot locomotion (section)

== Types of locomotion ==
=== Walking ===
* ''See'' [[Passive dynamics]]
* ''See'' [[Zero Moment Point]]
* ''See'' [[Leg mechanism]]
* ''See'' [[Hexapod (robotics)]]

[[File:F4-motion.gif|alt=Klann linkage|thumb|[[Klann linkage]] walking motion]] [[Walking robot]]s simulate human or animal [[gait]], as a replacement for wheeled motion. Legged motion makes it possible to negotiate uneven surfaces, steps, and other areas that would be difficult for a wheeled robot to reach, as well as causes less damage to environmental terrain as wheeled robots, which would erode it.<ref>{{cite thesis |url=http://www.amandaghassaei.com/files/thesis.pdf |title=The Design and Optimization of a Crank-Based Leg Mechanism |author=Ghassaei, Amanda |date=20 April 2011 |publisher=Pomona College |access-date=18 October 2018|archive-url=https://web.archive.org/web/20131029234530/http://www.amandaghassaei.com/files/thesis.pdf |archive-date=29 October 2013 |url-status=live}}</ref>

Hexapod robots are based on insect locomotion, most popularly the [[cockroach]]<ref>{{cite web|url=https://hub.jhu.edu/2018/02/13/cockroach-locomotion-robotics-research/|title=By studying cockroach locomotion, scientists learn how to build better, more mobile robots|last=Sneiderman|first=Phil|date=13 February 2018|work=Hub|publisher=[[Johns Hopkins University]]|access-date=18 October 2018}}</ref> and [[stick insect]], whose neurological and sensory output is less complex than other animals. Multiple legs allow several different gaits, even if a leg is damaged, making their movements more useful in robots transporting objects.

Examples of advanced running robots include [[ASIMO]], [[BigDog]], [[HUBO|HUBO 2]], [[RunBot]], and [[Toyota Partner Robot]].

===Rolling===
In terms of energy efficiency on hard, flat surfaces, wheeled robots are the most efficient. This is because an ideal, non-deformable rolling (but not slipping) wheel loses no energy. This is in contrast to [[legged robot]]s which suffer an impact with the ground at [[Heel strike (gait)|heel strike]] and lose energy as a result.[[Image:Segway 01.JPG|thumb|right|[[Segway PT|Segway]] in the Robot museum in [[Nagoya]]]]
For simplicity, most mobile robots have four [[wheel]]s or a number of [[continuous track]]s. Some researchers have tried to create more complex wheeled robots with only one or two wheels. These can have certain advantages such as greater efficiency and reduced parts, as well as allowing a robot to navigate in confined places that a four-wheeled robot would not be able to.

Examples:
[[Boe-Bot]],
[[Cosmobot]],
[[Elmer (robot)|Elmer]],
[[Elsie (robot)|Elsie]],
[[Enon (robot)|Enon]],
[[HERO (robot)|HERO]],
[[IRobot Create]],
[[iRobot]]'s Roomba,
[[Johns Hopkins Beast]],
[[Land Walker]],
[[Modulus robot]],
[[Musa (robot)|Musa]],
[[Omnibot]],
[[PaPeRo]],
[[Phobot]],
[[Pocketdelta robot]],
[[Push the Talking Trash Can]],
[[RB5X]],
[[Rovio (robot)|Rovio]],
[[Seropi]],
[[Shakey the robot]],
[[Sony Rolly]],
[[Spykee]],
[[TiLR]],
[[Topo (robot)|Topo]],
[[TR Araña]], and
[[Wakamaru]].

===Hopping===
Several robots, built in the 1980s by [[Marc Raibert]] at the [[Massachusetts Institute of Technology|MIT]] Leg Laboratory, successfully demonstrated very dynamic walking. Initially, a robot with only one leg, and a very small foot, could stay upright simply by [[wikt:hop|hopping]]. The movement is the same as that of a person on a [[pogo stick]]. As the robot falls to one side, it would jump slightly in that direction, in order to catch itself.<ref>{{cite web|url=http://www.ai.mit.edu/projects/leglab/robots/3D_hopper/3D_hopper.html|publisher=MIT Leg Laboratory|title=3D One-Leg Hopper (1983–1984)|access-date=2007-10-22}}</ref> Soon, the algorithm was generalised to two and four legs. A bipedal robot was demonstrated running and even performing [[somersault]]s.<ref>{{cite web|url=http://www.ai.mit.edu/projects/leglab/robots/3D_biped/3D_biped.html|publisher=MIT Leg Laboratory|title=3D Biped (1989–1995)}}</ref> A [[quadrupedalism|quadruped]] was also demonstrated which could [[trot (horse gait)|trot]], run, [[Horse gait#Pace|pace]], and bound.<ref>{{cite web|url=http://www.ai.mit.edu/projects/leglab/robots/quadruped/quadruped.html|publisher=MIT Leg Laboratory|title=Quadruped (1984–1987)}}</ref>

Examples:
* The MIT cheetah cub is an electrically powered quadruped robot with passive compliant legs capable of self-stabilizing in large range of speeds.<ref>{{Cite journal|last=A. Spröwitz, A. Tuleu, M. Vespignani, M. Ajallooeian, E. Badri, A. J. Ijspeert|date=2013|title=Towards dynamic trot gait locomotion: Design control and experiments with cheetah-cub a compliant quadruped robot|url=http://infoscience.epfl.ch/record/184991|journal=The International Journal of Robotics Research|volume=32|issue=8|pages=932–950|doi=10.1177/0278364913489205|s2cid=90770}}</ref> 
* The Tekken II is a small quadruped designed to walk on irregular terrains adaptively.<ref>{{Cite journal|last=H. Kimura, Y. Fukuoka, A. H. Cohen|date=2004|title=Biologically inspired adaptive dynamic walking of a quadruped robot|journal=Proceedings of the International Conference on the Simulation of Adaptive Behavior|pages=201–210}}</ref>

===Metachronal motion===
Coordinated, sequential mechanical action having the appearance of a traveling wave is called a [[metachronal rhythm]] or wave, and is employed in nature by [[ciliate]]s for transport, and by [[worm]]s and [[arthropod]]s for locomotion.

===Slithering===
Several [[snake]] robots have been successfully developed. Mimicking the way real snakes move, these robots can navigate very confined spaces, meaning they may one day be used to search for people trapped in collapsed buildings.<ref>{{cite web|url=http://www.snakerobots.com/|publisher=snakerobots.com|title=Introduction|first=Gavin|last=Miller|access-date=2007-10-22}}</ref> The Japanese ACM-R5 snake robot<ref>[http://www-robot.mes.titech.ac.jp/robot/snake/acm-r5/acm-r5_e.html ACM-R5] {{webarchive|url=https://web.archive.org/web/20111011030934/http://www-robot.mes.titech.ac.jp/robot/snake/acm-r5/acm-r5_e.html |date=2011-10-11 }}</ref> can even navigate both on land and in water.<ref>{{Cite web |url=http://video.google.com/videoplay?docid=139523333240485714 |title=Swimming snake robot (commentary in Japanese) |access-date=2011-10-26 |archive-date=2012-02-08 |archive-url=https://web.archive.org/web/20120208074204/http://video.google.com/videoplay?docid=139523333240485714 |url-status=dead }}</ref>

Examples:
[[Snake-arm robot]],
[[Roboboa]], and
[[Snakebot]].

===Swimming===
*''See'' [[Autonomous underwater vehicle]]s
===Flying===
*''See'' [[Unmanned aerial vehicle]]

===Brachiating===
{{see also|Brachiation}}
Brachiation allows robots to travel by swinging, using energy only to grab and release surfaces.<ref>{{Cite web|date=2019-03-18|title=Video: Brachiating 'Bot Swings Its Arm Like An Ape|url=https://www.popsci.com/technology/article/2012-05/video-gibbot-brachiating-bot-swings-its-arm-ape/|access-date=2021-07-30|website=Popular Science|language=en-US}}</ref> This motion is similar to an ape swinging from tree to tree. The two types of brachiation can be compared to bipedal walking motions (continuous contact) or running (ricochetal). Continuous contact is when a hand/grasping mechanism is always attached to the surface being crossed; ricochetal employs a phase of aerial "flight" from one surface/limb to the next.

===Hybrid===
Robots can also be designed to perform locomotion in multiple modes. For example, the Reconfigurable Bipedal Snake Robot<ref>Rohan Thakker, Ajinkya Kamat, Sachin Bharambe, Shital Chiddarwar and K. M. Bhurchandi. “ReBiS- Reconfigurable Bipedal Snake Robot.” In Proceedings of the 2014 IEEE/RSJ International Conference on Intelligent Robots and Systems, 2014.</ref> can both slither like a snake and walk like a biped robot.