Snakes & Snake Robots

How snakes move

How Do Snakes Move Without Legs? The Answer Is Incredible

THE SCIENCE BEHIND SURVIVAL · YouTube

How Snakes Move! (They don't just slither!)

Snake Discovery · YouTube

How snakes move: Muscle activity of rectlinear locomotion of boa constrictors

Bruce Jayne · YouTube

Lateral undulation: a wave of sideways bends travels down the body. Contact with the ground or surrounding objects supplies the forces that move the snake forward.

Sidewinding: sideways bending combines with lifting. Some body regions remain planted while others move to new contact points.

Concertina: the snake anchors part of its body, extends another part, then draws the rest forward. This is useful in tight passages and on branches.

Rectilinear motion: muscles move the belly skin and scales relative to the skeleton, so a heavy snake can creep forward with little sideways bending.

Snake robots

Newest featured designs and versions first, followed by earlier machines. Current product families appear at the top; dates identify the work shown.

Browse the robots

Current S-series · Trondheim, Norway

Eelume S-series and its snake-robot lineage

The current S3 catalog offers 300 m or 600 m depth ratings, up to 11 hours / 62 km depending on payload, multi-aperture sonar and a 4K still camera. S6 is rated to 600 m with synthetic-aperture sonar and configurable multi-day operation. The manufacturer describes articulated maneuvering, close terrain following and acoustic communication. These figures describe the current S-series, not every earlier long, slender Eelume inspection robot.

[16] [17] [18]

Current Eelume S3 manufacturer illustration. Source: Eelume product catalog. — Current Eelume S3 manufacturer illustration. [16]

Current Eelume S6 manufacturer illustration. Source: Eelume product catalog. — Current Eelume S6 manufacturer illustration. [16]

Eelume manufacturer illustration of the mission workflow. [16]

Eelume deployment and support package, manufacturer illustration. [16]

Eelume is a Game-changer for Subsea IMR

Marine Technology TV · YouTube

Eelume autonomous underwater vehicle

Kongsberg Maritime · YouTube

Eelume - Reshaping Underwater Operations

Kongsberg Maritime · YouTube

Slangerobot på havbunnen - Eelume underwater robot | NTNU

NTNU · YouTube

Gassco Eelume

Gassco AS · YouTube

Eelume (teaser)

Eelume Subsea Intervention · YouTube

Eelume - The Explorer Norway

Innovasjon Norge · YouTube

Current Soryu-C · hibot, Japan

Soryu-C

The current listing gives a main-unit envelope of 1720 × 94.5 × 79.5 mm, mass 10.5 kg, speed 100 mm/s and traction force 49 N. The tether is 150 m. Two HD cameras support inspection. The manufacturer rates the main unit IP67 and specifies insertion through openings as small as 100 mm diameter. A separate reel has different dimensions and protection.

[58] [59] [60]

Manufacturer press-release photograph. [61]

Soryu-C

hibot Corporation · YouTube

HiBot Inspection robot SORYU4 - Police Demonstration

Michele Guarnieri · YouTube

Earlier SORYU4 inspection robot, distinct from the current Soryu-C.

Current Float Arm · hibot, Japan

Float Arm

A self-balancing articulated arm for confined-space inspection and maintenance. The published specification is 5 m extended length, 35 kg mass, 2.5 kg payload and up to nine links. Possible tools include HD or thermal cameras, ultrasonic probes, lidar and time-of-flight cameras. It follows a confined path as an arm rather than crawling independently across the floor.

[62] [63]

Float Arm in an industrial inspection setting. Source: hibot press release. — Float Arm in an industrial inspection setting. [64]

Float Arm - long reach arm for inspection and maintenance

hibot Corporation · YouTube

hibot at iREX 2025!

hibot Corporation · YouTube

FloatArm Concept

hibot Corporation · YouTube

Float Arm concept presentation; distinguish the illustrated mechanism from deployed inspection footage.

hibot at Maintenance & Resilience Tokyo 2025 - Float Arm & SQUID Robots in Action!

hibot Corporation · YouTube

TOKYO IREX22 hibot VirtualShow

hibot Corporation · YouTube

Broader hibot exhibition presentation with multiple platforms.

Current modular hardware · HEBI Robotics, USA

HEBI modular actuator

HEBI’s modular electric actuators combine a geared joint, sensing and control electronics. Their hardware documentation includes CAD, connector details and programming interfaces, making them one route to assembling a modular snake body.

[88] [89] [90]

HEBI X5 and X8 modular electric actuators, manufacturer photograph. [88]

Current platform · roboa / ETH Zürich lineage · Switzerland

roboa

roboa advances by turning its soft tube inside out at the tip, so the body grows into a passage. A base supplies the tube and operating services, while interchangeable heads support inspection or cable deployment. The earlier ETH research prototype used pneumatic steering and a sensor head for search-and-rescue experiments. The current manufacturer lists an additional steering module as coming soon.

[135] [136]

roboa: manufacturer overview image. [135]

RoBoa research prototype: supply and control box (2021 paper). [136]

RoBoa research prototype: soft tube and steering construction (2021 paper). [136]

RoBoa research prototype in a collapsed-building test environment (2021 paper). [136]

Meet roboa - The robotic revolution to inspect and work in confined spaces.

roboa · YouTube

2026 revision · UC San Diego, USA

ARCSnake V2

Water-sealed screw modules combine body articulation with Archimedean screw propulsion. V2 adds buoyancy control for diving and surfacing. The paper describes a 48 V tethered power rail, local conversion to 24 V, a buoyancy bladder system, and joint tests that expose load-dependent hysteresis. Underwater experiments support its amphibious capabilities; exploration and rescue remain proposed applications.

[1] [2] [3]

ARCSnake V2 underwater test sequence. Wickenhiser et al., 2026 revision, Figure 1. [2]

Screw modules, seals, joint internals and buoyancy components. Wickenhiser et al., Figure 2. [2]

Sample-collection head and its linkage. Wickenhiser et al., Figure 4. [2]

ARCSnake: Reconfigurable Snake-Like Robot w/ Archimedean Screw Propulsion for Multi-Domain Mobility

UCSD Advanced Robotics and Controls Lab · YouTube

Original ARCSnake platform; this is not the V2 paper demonstration.

ICRA2020 Presentation: ARCSnake: Archimedes Screw-Propelled Robot for Extra-terrestrial Environments

UCSD Advanced Robotics and Controls Lab · YouTube

ARCSnake: An Archimedes' Screw-Propelled, Reconfigurable Robot Snake for Complex Environments

UCSD Advanced Robotics and Controls Lab · YouTube

2026 · KIST / UNIST and collaborators, South Korea

Tendon-driven wheel-free continuum snake

The 1.25 m, 2.21 kg prototype has 13 motor modules and 12 compliant joints. Local tendon actuation creates the planar wave; centrally placed additional drives tension body-length dorsal, ventral and spiral tendons to alter lift and twist. Coil springs surround a flexible backbone. Demonstrated forward, backward and sidewinding speeds were 27.6, 35.5 and 20.0 mm/s on an indoor surface. Torsional backlash and flipping limited speed.

[4] [5]

Tendon-driven snake: body layout and module photographs. Source: 2024 precursor preprint, rather than a separate photograph of the 2026 revision. — Tendon-driven snake: body layout and module photographs. Photograph or design figure from the team’s 2024 prototype paper. [6]

Tendon-driven snake: body lifting and compliant bending. Source: 2024 precursor preprint, rather than a separate photograph of the 2026 revision. — Tendon-driven snake: body lifting and compliant bending. Photograph or design figure from the team’s 2024 prototype paper. [6]

Tendon-driven snake: twisting motion and body contact. Source: 2024 precursor preprint, rather than a separate photograph of the 2026 revision. — Tendon-driven snake: twisting motion and body contact. Photograph or design figure from the team’s 2024 prototype paper. [6]

Tendon-driven snake: continuum-section CAD and tendon routing. Source: 2024 precursor preprint, rather than a separate photograph of the 2026 revision. — Tendon-driven snake: continuum-section CAD and tendon routing. Photograph or design figure from the team’s 2024 prototype paper. [6]

Tendon-Driven Compliant Wheel-less Snake Robot for Undulatory Locomotion (AISy 2026)

Junhyoung Ha · YouTube

Snake Robot Demo at Army M&S Conference 2024 #UNIST #snake #robot #locomotion

Junhyoung Ha · YouTube

Robotic Snake Locomotion Exploiting Body Compliance (IEEE T-RO 2023)

Junhyoung Ha · YouTube

UNIST Snake Robot at KRoC 2024 Red Show

Junhyoung Ha · YouTube

UNIST Snake Robot Outdoor Filed Test #UNIST #snake #robot #locomotion

Junhyoung Ha · YouTube

2026 field deployment · Carnegie Mellon University, USA

CMU snake robots in field search

CMU reports using camera-equipped snake robots to inspect collapsed buildings in Venezuela from June 30 to July 3, 2026. Operators returned images from spaces responders could not enter. The team did not locate survivors. Equipment repairs, power, communications and logistics were part of the field experience. Earlier CMU deployment documentation covers the 2017 Mexico City earthquake.

[13] [14] [15]

CMU team presenting the robot during the reported Venezuela deployment. Source: Carnegie Mellon University. — CMU team presenting the robot during the reported Venezuela deployment. [13]

Transport case and field equipment. Source: Carnegie Mellon University. — Transport case and field equipment. [13]

The snake robot in rubble after inspection. Source: Carnegie Mellon University. — The snake robot in rubble after inspection. [13]

Remote operation during the reported Venezuela search, photographed by Carnegie Mellon University. [13]

Scouting and Recon - Snake Robots

CMUBiorobotics · YouTube

Carnegie Mellon - Ryerson Canine Assisted Snake Robot Deployment

CMUBiorobotics · YouTube

Innovative snake robot from CMU tackles urban rescues and surgeries

WTAE-TV Pittsburgh · YouTube

Snake Robot Demo at EPRI

EPRI · YouTube

2026 · Umit Sen, Andri Mahegan and Gina Olson

Replaceable scale pseudo-skin

A modular articulated skin allows scales to be removed or replaced. Experiments compare scale attack angles of 15°, 25°, 35° and 45° on grass, bark, carpet and a smooth surface, measuring both friction and robot speed. The expected relationship between friction ratios and speed was not consistent. Surface interaction cannot be reduced to a single anisotropy number.

[19]

Pneumatic body and removable scale skin. Sen, Mahegan and Olson, 2026, Figure 1. [20]

Vertebrae, ribs and scale assembly. Sen, Mahegan and Olson, Figure 2. [20]

Locomotion sequence on bark. Sen, Mahegan and Olson, Figure 7. [20]

Scale-skin robot: actuator and skin fabrication steps from the primary paper. [20]

2026 · Henry C. Astley, University of Akron, USA

Skin Deep: cutaneous rectilinear control

The test robot uses 12 Dynamixel XL330-M288-T motors, printed brackets, an inert front segment and an OpenRB-150 controller. All motor axes are horizontal, producing vertical bending. The algorithm assigns body regions scale-like and skin-like roles: a scale region lifts, advances as adjacent regions contract and extend, then returns to ground contact. Tests compare displacement, current and vertical clearance against propagating vertical waves. The paper reports code in its supplementary material and links an open data deposit.

[21] [22] [23]

2026 · GaryZhous / University of Toronto capstone, Canada

ESP32 SnakeRobot capstone

The repository supplies Arduino/ESP32 sketches, a Python Bluetooth interface, wiring notes and printable CAD meshes. It lists a BNO08x IMU and PMW3901 optical-flow sensor for feedback, with a fixed 0.5 Hz gait in the described controller. Calibration and later position-control firmware are separated. The README reports a University of Toronto capstone poster from March 26, 2026.

[86] [87]

The 2026 project poster with architecture and build photographs. Source: GaryZhous/SnakeRobot repository. — The 2026 project poster with architecture and build photographs. [86]

2025 · Tiangong University and collaborators, China

JiAo-II

Each module uses a joint motor, a wheel motor, two elliptical wheels and a bevel-gear transmission. Adjacent pitch and yaw modules are orthogonal. Both motor roles use Dynamixel XH430-W350-R actuators. Printed housings and transmissions package the wheels into the body profile. Tests cover grass, gaps, slopes, pipes and cylindrical climbing, alongside coordinated wheel/body motion on uneven ground.

[7] [8]

JiAo-II overall layout and dimensions. Xiao et al., 2025, Figure 2. [7]

Joint and wheel motors with the gear transmission. Xiao et al., Figure 3. [7]

Elliptical-wheel geometry and body profile. Xiao et al., Figure 4. [7]

JiAo-II control architecture. Xiao et al., Figure 6. [7]

2025 · Northeastern University, USA

COBRA

An 11-DOF articulated robot can change posture for slithering, tumbling and object interaction. The 2025 vision paper combines YOLOv8 detection with stereo depth and object pose estimation; its reported manipulation experiments were open loop. A separate December 2025 master's thesis reports physical waypoint-navigation experiments using visual-inertial localization, center-of-mass estimation and closed-loop adjustment of CPG gait parameters.

[9] [10] [11]

COBRA approaching a manipulation target. Salagame et al., 2025, Figure 1. [12]

COBRA head, docking components and onboard computing. Salagame et al., Figure 3. [12]

Loco-manipulation experiment sequence. Salagame et al., Figure 9. [12]

COBRA system architecture and onboard subsystems, primary paper Figure 2. [12]

2023–24 · NASA Jet Propulsion Laboratory, USA

NASA / JPL EELS

JPL's project page lists EELS 1.0 at 4.4 m and 100 kg. Rotating screw surfaces provide traction and grip in snow, sand and ice while articulation changes the body shape. The head uses lidar and four stereo camera pairs for mapping, with risk-aware autonomy. Glacier tests include a separate 1.5 configuration for subsurface autonomy. A potential Enceladus application inspired the work; this is not a flown spacecraft or a confirmed mission.

[24] [25] [26]

EELS hardware on Athabasca Glacier, 2023. NASA/JPL-Caltech. [24]

Physical screw-driven surface on an EELS prototype. NASA/JPL-Caltech. [24]

Glacier testing of the sensing head. NASA/JPL-Caltech. [24]

Concept illustration of EELS in an icy passage. This is a rendering, not a field photograph. NASA/JPL-Caltech. [24]

Testing Out JPL’s New Snake Robot

NASA Jet Propulsion Laboratory · YouTube

Exobiology Extant Life Surveyor (EELS) Concept of Operations on Enceladus

JPLraw · YouTube

Mission concept animation, not footage of a robot operating on Enceladus.

Robot snakes in space? But first, NASA is testing them on an Alberta glacier

CBC News · YouTube

EELS (Exobiology Extant Life Surveyor) snake-like robot for space exploration by NASA/JPL-Caltech

MechDesignTV · YouTube

2024 · Beyza Seyidoğlu / Ahmad Rafsanjani and collaborators, Denmark

Textile-origami rectilinear snake

A soft robot uses a textile-origami structure to produce rectilinear progress. Reported tests use a four-module sequence at 28 kPa and approximately 183 mm/min on plastic, with lower speeds on foam and soil. These values describe the stated test setup. The full article and supplements are the place to inspect fabrication methods and motion sequences.

[70] [71]

Textile-origami rectilinear robot, original paper Figure 1. Seyidoğlu and collaborators, Device. [72]

Textile-origami rectilinear robot, original paper Figure 2. Seyidoğlu and collaborators, Device. [72]

Textile-origami rectilinear robot, original paper Figure 3. Seyidoğlu and collaborators, Device. [72]

Textile-origami rectilinear robot, original paper Figure 4. Seyidoğlu and collaborators, Device. [72]

A textile origami snake robot for rectilinear locomotion | Device (2024)

SDU Soft Robotics · YouTube

Researchers present new snake robot made of origami folded textiles

Ingeniøruddannelserne på Syddansk Universitet · YouTube

RoboSoft 2024 | Metamaterial soft snake robot for rectilinear locomotion

SDU Soft Robotics · YouTube

2023 research · Tohoku University and collaborators, Japan

Dragon Firefighter

Dragon Firefighter lifts and steers a flexible firefighting hose using controlled water jets. Fluid reaction forces support the body and aim the nozzle above obstacles. It is a tethered continuum robot with a very different propulsion system from a ground-crawling snake.

[75] [73]

Dragon Firefighter: full system and water-jet locomotion overview, primary paper Figure 1. [76]

Dragon Firefighter: hoses, mobile base and nozzle units, Figure 2. [76]

Dragon Firefighter: nozzle-unit parts and servo assembly, Figure 5. [76]

Dragon Firefighter: swivel joint, pitch nozzle and roll nozzle hardware, Figure 6. [76]

Scientists develop 'flying dragon' robot to fight fires from a distance

Science X · YouTube

Dragon Firefighter Robot Fights Fires from a Distance

DroneLife TV · YouTube

2023 · Rozaidi and collaborators, USA

HISSbot

The Helical Inflating Soft Snake Robot demonstrates spatial sidewinding using compliant actuation. The authors report locomotion tests on multiple surfaces, including low-friction and granular media.

[91]

HISSbot physical soft body in a spatial configuration. Original authors’ paper. [92]

HISSbot actuator end components and fittings. Original authors’ paper. [92]

HISSbot assembled hardware in the locomotion experiment. Original authors’ paper. [92]

HISSbot sidewinding sequence across granular media. Original authors’ paper. [92]

2023 · Konishi, Nakajima, Tanaka and collaborators, Japan

Partial-grasping pipe locomotion

The work studies motion along or around a pipe while using partial grasping rather than a full-body wrap. The publisher record reports experiments negotiating an obstacle on a pipe. It supplies another contact strategy for constrained supports beyond a uniform rolling helix.

[101]

Development of Snake Robots：Super snake robots and disaster response, Tanaka Lab.

電気通信大学VideoUEC · YouTube

Tanaka laboratory overview with multiple robot designs; not exclusively the partial-grasping paper.

2019 / 2022 redesign · Norwegian research teams including UiA / OsloMet

Serpens and redesigned Serpens

The 2019 design uses a Dynamixel XM430-W210-class actuator with a compliant joint, stereoscopic vision and a screw-less modular interface. Its reported module is about 500 g, 75 mm across, with 200 mm between joint axes and ±90° travel. The 2022 redesign adds damping, a stronger latch, revised thermal packaging and better battery access. It uses output-side sensing to compare motor and load motion. The redesign paper includes preliminary simulations, not proof of autonomous rescue.

[46] [47] [48]

Serpens prototype with stereoscopic sensing head. Sanfilippo et al., 2019, Figure 1. [46]

Serpens compliant joint configurations. Sanfilippo et al., Figure 3. [46]

Exploded Serpens module. Sanfilippo et al., Figure 4. [46]

Redesigned screw-less latch, shown as CAD. Duivon et al., 2022, Figure 1. [47]

Redesigned module packaging, shown as CAD. Duivon et al., Figure 2. [47]

2022 · Ramesh, Fu and Li, Johns Hopkins University, USA

SenSnake contact-force research robot

The primary paper reports a 12-segment robot with 36 piezoresistive sheet sensors sampled at 30 Hz. The system measures contact forces during repeatable obstacle-traversal experiments. Sensor behavior and calibration are part of the work, including the viscoelastic response of the sensing material.

[93] [94]

SenSnake instrumented body, compliant shell and sensor construction, Figure 1. Primary paper, PDF page 2. [95]

SenSnake contact sensing and calibration, original experimental figures. Primary paper, PDF page 3. [95]

SenSnake obstacle traversal with measured contact forces, Figure 5. Primary paper, PDF page 4. [95]

SenSnake sensor attachment and robustness tests, Figure 7. Primary paper, PDF page 5. [95]

SenSnake: A snake robot with contact force sensing for studying locomotion in complex 3-D terrain

Terradynamics Lab · YouTube

SenSnake: A snake robot with contact force sensing for studying locomotion in complex 3-D terrain

Terradynamics Lab · YouTube

Robotic snake traversing large obstacles using vertical bending with contact force feedback

Terradynamics Lab · YouTube

A snake robot to study force generation and control of limbless locomotion in 3-D terrain

Terradynamics Lab · YouTube

2021 · Carnegie Mellon University, USA

HUMRS underwater snake

Hardened Underwater Modular Robot Snake research extends modular snake hardware to underwater inspection and confined spaces such as ballast tanks. Watertight modules and aquatic mobility address access problems that rigid vehicles cannot easily solve. Lab work includes navigation, inspection and environmental interaction. These research goals should not be read as an operational fleet with fully autonomous confined-space inspection.

[34] [35] [36]

HUMRS during a pool test. Source: Carnegie Mellon University. — HUMRS during a pool test. [37]

Underwater head and propulsion hardware. Source: Carnegie Mellon University. — Underwater head and propulsion hardware. [37]

Hardened Underwater Modular Robot Snake (HUMRS)

Carnegie Mellon University · YouTube

HUMRS

M R · YouTube

2020 · Liao, Zang and collaborators, China

Soft rod-climbing robot with two winding grips

The specialized tethered climber alternates winding grips and length change to progress along a rod. The publisher abstract reports vertical climbing up to 30.85 mm/s and turning around a corner along a rod. Those results belong to the reported test geometry and pneumatic setup; they are not a universal tree-climbing specification.

[100]

2019 · Koopaee and collaborators, University of Canterbury, New Zealand

Wheel-free pedal-wave snake with active stiffness control

This research develops a modular wheel-free snake with series elastic actuators to study torque measurement and active stiffness control. The design connects adaptation over uneven terrain and to modeling the interaction between actuator compliance and the body wave.

[98]

Active-stiffness snake: elastic element CAD, finite-element analysis and manufactured part, Figure 1. Primary paper, PDF page 21. [99]

Active-stiffness snake: body and connector design, Figure 3. Primary paper, PDF page 23. [99]

Active-stiffness snake: assembled module CAD, Figure 4. Primary paper, PDF page 24. [99]

Active-stiffness snake: pedal-wave progression in hardware, Figure 6. Primary paper, PDF page 26. [99]

2018 · Harvard Wyss Institute / SEAS, USA

Kirigami soft crawler

A patterned skin wrapped around an extending soft actuator opens into protruding scale-like features. Inflation changes the geometry and ground interaction, allowing repeated extension/contraction cycles to advance the body. It uses soft actuation and surface design rather than a chain of rotary servo joints.

[68] [69]

Kirigami skin stretched into raised friction features. Ahmad Rafsanjani / Harvard SEAS. [68]

Kirigami crawler physical hardware. Harvard Wyss Institute / SEAS source photograph. [68]

Kirigami crawler: original Harvard demonstration still. [69]

Snakeskin Robot

Harvard University · YouTube

Snake-inspired robot slithers even better than predecessor

Harvard John A. Paulson School of Engineering and Applied Sciences · YouTube

Artificial Snakeskin Helps Robots Get Their Slither On

IEEE Spectrum · YouTube

Technologies inspired by kirigami, origami, and snakes [NSF]

National Science Foundation News · YouTube

2018 · Luo and collaborators, USA

OriSnake

OriSnake is a lightweight origami-based snake using continuum modules for spatial locomotion, including lateral undulation and sidewinding. Its design and fabrication paper provides a separate construction approach from rigid servo brackets and from textile-origami rectilinear robots.

[96]

OriSnake physical robot and origami module layout, Figure 1. Primary paper, PDF page 2. [97]

OriSnake module kinematics, Figure 2. Primary paper, PDF page 2. [97]

OriSnake support module: CAD geometry and physical prototype, Figure 3. Primary paper, PDF page 3. [97]

OriSnake locomotion experiment sequence, Figure 8. Primary paper, PDF page 5. [97]

OriSnake: Design, Fabrication and Experimental Analysis of a 3-D Origami Snake Robot

ming luo · YouTube

2010s industrial systems · United Kingdom / GE industrial inspection lineage

OC Robotics snake arms

OC Robotics’ cable-driven snake arms carry cameras or tools into confined machinery. A supported base carries the load while successive sections follow the tip’s path. The industrial demonstrations include access inside aircraft engines.

[77]

OC Robotics industrial snake-arm system. Source: GE News. — OC Robotics industrial snake-arm system. [77]

JetSnake inspection hardware in an engine setting. Source: GE News. — JetSnake inspection hardware in an engine setting. [77]

LaserSnake operator control station. GE News / OC Robotics. [77]

LaserSnake inspection and cutting arm. GE News / OC Robotics. [77]

2017 · Fabian Reyes / Ritsumeikan University, Japan

OPPAS parametric snake robot

The author provides a Fusion 360 parametric design and documentation, with a GrabCAD download route. Mk. 1.0 targets ROBOTIS MX-64 servos. Link dimensions and belly features are intended to be changed without redesigning every component. The author explicitly lists waterproofing and broader servo support as future improvements. The repository identifies a CC BY 4.0 license.

[82] [83] [84]

OPPAS open parametric module design. Fabian Reyes / Ritsumeikan BioInMech, CC BY 4.0. [83]

2014 · Carnegie Mellon University, USA

CMU series elastic snake

Series elastic joints place a spring between motor transmission and output. Deflection provides a route to torque feedback and passive compliance during environmental contact. CMU's modular architecture separates actuator, electrical interface and controller responsibilities. Related lab pages also discuss reusing modules in other configurations, including legged robots; those are separate machines.

[31] [32] [33]

Series elastic modular actuator hardware. Source: CMU Biorobotics Laboratory. — Series elastic modular actuator hardware. [32]

CMU series-elastic snake: motor, spring and sensing cutaway, Figure 3. Primary paper, PDF page 2. [31]

CMU series-elastic snake: mechanical impedance and spring arrangement, Figure 5. Primary paper, PDF page 3. [31]

CMU series-elastic snake: intermodule construction, Figure 6. Primary paper, PDF page 3. [31]

Series Elastic Snake Robot - Overview

CMUBiorobotics · YouTube

Shape-based Compliant Control of a Snake Robot

CMUBiorobotics · YouTube

Snake Robot Torque Control Strategies

IEEE Spectrum · YouTube

2010s · NTNU / SINTEF ROBOTNOR, Norway

Mamba

Mamba was developed as a modular, reconfigurable snake with watertight joints and contact-force sensing. The body was designed for interaction with obstacles and possible aquatic operation; the original development page describes some capabilities as goals.

[53] [54]

Mamba module concept rendering. Source: NTNU/SINTEF ROBOTNOR. — Mamba module concept rendering. [53]

Mamba primary experiment paper: underwater snake kinematic model, Figure 1. [55]

Mamba swimming in the experimental tank, Figure 3. [55]

Mamba experimental tank instrumentation and tracking arrangement, Figure 10. [55]

Underwater Robot Snake

NTNU Cybernetics · YouTube

Swimming Snake Robot Mamba Controlled using Virtual Holonomic Constraints

Robotic Motion Intelligence Lab · YouTube

2012 · Carnegie Mellon University, USA

CMU Unified modular snake

The Unified design packages a custom actuator transmission, sensors, electrical interconnection and a holding brake into modular units. Alternating joint-axis orientations allow 3D body shapes. The team's gait library demonstrates sidewinding, rolling, climbing and related motions. Performance depends on contact geometry and the environment, not just on playing a sinusoid through the joints.

[27] [28] [29]

Unified Snake climbing a tree. Wright et al., ICRA 2012, Figure 1. [27]

Unified Snake actuator layout. Wright et al., ICRA 2012. [27]

Unified Snake exploded housing. Wright et al., ICRA 2012. [27]

Unified Snake motor and parking brake. Wright et al., ICRA 2012. [27]

Intermodule connector and encoder. Wright et al., ICRA 2012. [27]

Compliant rubber contact covering. Wright et al., ICRA 2012. [27]

CMUModsnake · YouTube

CMU Snake Robot climbing loose sand

dgoldmanlab · YouTube

2010s · NTNU / SINTEF ROBOTNOR, Norway

Kulko

Kulko studies obstacle-aided locomotion. Contact sensing tells the controller where the body meets its surroundings, allowing obstacles to become useful push points.

[51] [52]

Kulko contact-sensing research platform. Source: NTNU/SINTEF ROBOTNOR. — Kulko contact-sensing research platform. [51]

Kulko obstacle aided motion

ROBOTNOR (Norway) · YouTube

The snake robot Kulko - Obstacle-aided locomotion

advancedrobots · YouTube

KulKo: Snake robot obstacle aided locomotion

sigurdfjerdingen · YouTube

2000s · NTNU / SINTEF ROBOTNOR, Norway

Wheeko

Ten identical modules each provide two motorized degrees of freedom. Passive wheels create low rolling resistance along the body and higher resistance laterally. The lab lists 960 g per joint module, 130 mm outer diameter, ±45° travel, 4.5 N·m maximum continuous torque and 70°/s no-load speed. These are module specifications, not whole-robot values.

[49]

Wheeko and its passive wheels. Source: NTNU/SINTEF ROBOTNOR. — Wheeko and its passive wheels. [49]

Wheeko research paper: articulated-chain kinematics, Figure 1. [50]

Wheeko

ROBOTNOR (Norway) · YouTube

The snake robot Wheeko

advancedrobots · YouTube

Straight line path following control of the snake robot Wheeko

advancedrobots · YouTube

2000s onward · Tohoku University and collaborators, Japan

Active Scope Camera

Active Scope Camera is a flexible inspection probe that propels itself into narrow voids. Versions use vibrating cilia for traction and air jets to lift or direct the head. Its rescue applications emphasize insertion, tether management and a useful camera view.

[73] [74]

Active Scope Camera inspection hardware, Tohoku University / IRIDeS. [73]

ImPACTタフ・ロボティクス・チャレンジ　研究開発ストーリー（通常版）

ImPACT Tough Robotics Challenge · YouTube

Active Scope Camera For Use In Emergency Situations : DigInfo

ikinamo · YouTube

Active Scope Camera by Tohoku University : DigInfo [HD] [CC]

ikinamo · YouTube

The New Drive Mechanism for Robots : DigInfo

ikinamo · YouTube

2006 · University of Maryland, USA

Spranklin rectilinear robot

Brent William Spranklin’s 2006 robot explored rectilinear travel through coordinated vertical body motion. The completed module shown below is Figure 5.19 from his University of Maryland thesis.

[67]

Spranklin’s completed robot module, Figure 5.19, thesis PDF page 184. [67]

2005 · Hirose, Mori, Yamada and Chigisaki, Japan

ACM-R5 amphibious robot

ACM-R5 is an important land-and-water branch of Hirose's research. The 2005 JSME conference record identifies the design and control work and its authors. It belongs alongside AmphiBot when comparing aquatic and terrestrial locomotion. The conference record is a historical source, not evidence of a newly released 2026 product.

[41] [39]

ACM-R5 on land. Original hibot brochure photograph; brochure specifications are historical. [42]

ACM-R5 during an aquatic demonstration. Original hibot brochure photograph; brochure specifications are historical. [42]

Amphibious snake robot - ACM-R5 : DigInfo

ikinamo · YouTube

HiBot Amphibious snake robot

Michele Guarnieri · YouTube

HiBot NEW ACM-R5H amphibious snake robot

Michele Guarnieri · YouTube

IREX 2013: HiBot Amphibious Snake Robot

Robots Dreams · YouTube

IREX 2013 HiBot booth ACM-R5H

Michele Guarnieri · YouTube

2000s · SINTEF / ROBOTNOR, Norway

Anna Konda

The lab lists a 3 m, 75 kg robot with 20 degrees of freedom and ±35° joint travel. Water hydraulics at 100 bar provide up to 300 N·m joint torque. Water is both an actuation resource and the firefighting medium. The heavy, powerful mechanism illustrates a different scale from hobby servo snakes. The available motion video establishes a moving prototype, not routine fire-service deployment.

[56] [57]

Anna Konda water-hydraulic prototype. Source: NTNU/SINTEF ROBOTNOR. — Anna Konda water-hydraulic prototype. [56]

Anna Konda - Spraying water

ROBOTNOR (Norway) · YouTube

Anna Konda. The Snake Robot

Luca De Nardo · YouTube

AnnaKonda Fire-Fighting Snake Robot

sigurdfjerdingen · YouTube

Anna Konda Firefighting Robot

BotJunkie · YouTube

2000s · University of Michigan, USA

OmniTread OT-4 / OT-8

OmniTread combines linked rigid segments with extensive tread coverage. Pneumatic articulation allows sections to lift or bridge terrain while the tracks continue providing traction. The OT-4 development is documented by the university and in a technical paper. Its tracks provide traction while its joints adapt the body to the terrain.

[65] [66]

OmniTread climbing a step. Historical demonstration reproduced in Spranklin’s thesis, Figure 2.14, crediting the Michigan robot research. [67]

2000s · Juan González-Gómez and collaborators, Spain

CUBE / Cube Reloaded / Unimod family

Juan González-Gómez’s CUBE and Cube Reloaded projects document modular servo bodies and traveling-wave locomotion. Cube Reloaded uses eight modules. The related Unimod and Minicube pages show real assembly steps and reusable mechanical designs.

[78] [79] [80]

Cube Reloaded physical modular body, original project photograph. [81]

CUBE and Cube Reloaded family hardware, original project photograph. [81]

Cube Reloaded dimensioned servo-link side view, original project drawing. [81]

Simulation or animation, as identified in the video title.

Cube Revolutions: Cobra shape (Blender animation)

Juan Gonzalez Gomez · YouTube

Simulation or animation, as identified in the video title.

2001–05 · Gavin Miller · USA

S7

Gavin Miller’s wheel-free S7 was intended to reproduce python-like rectilinear progression. The original page describes expanded PVC, steel rod and plastic gears, plus packet radio and extensive sensing. Construction photos show the body, sensor head and custom controllers. A complete belly-drive drawing and a verified public video of S7 locomoting have not been recovered.

[102]

S7: original photograph or technical drawing from Gavin Miller’s prototype page. [102]

2004 onward · EPFL BioRob, Switzerland

AmphiBot I–IV / Envirobot lineage

EPFL’s AmphiBot robots use body undulation to crawl and swim. The early versions combined motorized joints with central pattern generator control; the later lineage includes environmental monitoring platforms. Their demonstrations show how a traveling body wave changes between land and water.

[43] [44] [45]

AmphiBot III articulated swimming robot. Source: EPFL BioRob. — AmphiBot III articulated swimming robot. [43]

AmphiBot III steering demonstration, original EPFL video still. [43]

AmphiBot III swimming-race demonstration, original EPFL video still. [43]

AmphiBot III fin locomotion, original EPFL video still. [43]

AmphiBot III swimming race (complete version)

BIOROB · YouTube

EPFL Robotic Eel - Envirobot

TechTheLead · YouTube

Envirobot branch of the EPFL swimming-robot lineage.

Envirobot

Science Node · YouTube

Envirobot branch of the EPFL swimming-robot lineage.

1990s–2004 · Fraunhofer · Germany

MAKRO / MAKRO-PLUS

A wheeled sewer-inspection robot with six body sections and five powered joints. MAKRO 1.1 carries its batteries, computer and motor controllers onboard. Joint articulation lifts sections and turns the body through pipe junctions while the wheels supply traction. The 2004 paper reports a two-metre, approximately 50 kg prototype with 21 motors.

[104] [105]

MAKRO 1.1: original prototype and experiment photographs. [106]

MAKRO 1.1 physical prototype, Figure 1, Adria, Streich and Hertzberg (2004). [105]

Kanalroboter Makro von der GMD / Fraunhofer AIS / Fraunhofer IAIS

hsurmann · YouTube

Makro plus pipe robot

hsurmann · YouTube

Early 2000s · University College London · UK

MOBIUS smart-material snake

Peter Bentley and Siavash Haroun Mahdavi explored a snake whose shape-memory-alloy wires act as muscles. Heating contracts the wires; a learned control sequence coordinates their motion. The research investigated whether control could adapt after actuator damage.

[115]

MOBIUS: shape-memory-alloy robot, original project photograph. [115]

Documented by 2003 · Human Engineering Laboratory · USA

Berkeley electromechanical snake

Berkeley’s archived project page preserves photographs of an articulated electromechanical snake and a link to an AVI demonstration. The physical structure and joint arrangement are visible below; a complete fabrication package and a working copy of the linked movie have not been recovered.

[124]

Berkeley: original electromechanical snake prototype. [124]

2001–03 · Mark Sherman / Tennyson High School · USA

Slither

Slither uses ten bent-aluminum segments, nine hobby servos and wheels. A BasicX-24 controller coordinates the wave, accepts infrared-remote commands and responds to whisker switches. The original project gives construction details and code in a short report.

[129]

Slither: original project construction photograph. [129]

Make Podcast: Mark Sherman's Snake Robot

Make: · YouTube

Documented by 2003 · Robix · USA

Robix RCS-6 snake

A snake configuration built from the Robix RCS-6 robot construction set. Programmable servo sequences make the linked body bend and straighten; the original page demonstrates one possible configuration of the kit.

[131]

Early 2000s · University of Guelph · Canada

Pronavsys search-and-rescue prototype

This student prototype links three tracked bodies using steerable joints. Six DC motors drive the tracks, while servos adjust pitch and yaw. A tethered Motorola 68HC12 controller coordinates movement. The recovered report documents the electronics and construction; it is a locomotion prototype rather than a demonstrated survivor-locating system.

[133]

Pronavsys / Guelph prototype: joint hardware and assembled tracked body. [134]

Around 2001 · Sensor Based Planning Lab · USA

Early CMU modular snakes

CMU’s early snake experiments explored bending waves, three-dimensional motion and inspection access using articulated modules. The historical lab credited Mark Yim’s design for one of its modular platforms. These demonstrations precede the later Unified and series elastic snakes.

[116]

CMU’s early snake-robot research: original demonstration frame. [117]

1993–2002 · Swedish Institute of Computer Science · Sweden

PIRAIA / DRAGON

Martin Nilsson’s modular snake work combined roll–pitch–roll joints with research on learned locomotion, docking and distributed sensing. Physical joint design was chosen to make simulation and control tractable. The DRAGON stage also explored structures assembled from reconnectable modules.

[109] [110]

PIRAIA / DRAGON: original mechanism, prototype or experiment. [111]

1995–2000 · Metz, Bucharest and Warsaw · Europe

Metz / Copernicus microrobot

The Copernicus project studied a flexible robot for pipe inspection. Three miniature actuators change each module’s shape; repeating modules bend and extend the body. The team built an enlarged 20-module model with DC motors and CAN-connected Siemens C167 controllers before attempting the intended miniature scale.

[112]

Metz / Copernicus: original prototype and module design. [112]

Metz / Copernicus: physical robot locomotion

Original project footage. [140]

2000 · NASA Ames · USA

NASA Ames Snakebot

Ames investigated a modular snake for rough terrain, narrow gaps and future planetary exploration. The 2000 announcement describes a mechanical test platform and planned autonomous capabilities. It was a research prototype, separate from JPL’s much later EELS project.

[125]

NASA Ames Snakebot: original NASA prototype photograph. [126]

NASA Ames Designs Autonomous Robots

NASA's Ames Research Center · YouTube

1998–99 · Gavin Miller · USA

S5

Gavin Miller’s S5 combines a slim articulated body with 64 servos, polycarbonate structure, brass rods and segmented vinyl cladding. A Basic Stamp II and Scenix processor coordinate eight servo-control units over four serial buses. The original description lists 42 batteries and four-channel radio control. The surviving clips show its lifelike body waves and turning.

[103]

S5: original photograph or technical drawing from Gavin Miller’s prototype page. [103]

S5: circling

Original project footage. [141]

S5: side-view locomotion

Original project footage. [142]

S5: approaching the camera

Original project footage. [143]

1998–99 · GMD / Fraunhofer · Germany

GMD Snake2

Snake2 added powered wheels around each section for faster inspection travel. Three motors in a section adjust the joint between neighboring sections. The original page reports more than 12 N·m joint torque, about 0.1 m/s travel, and infrared, torque, tilt and other sensors. It is distinct from the first, body-propelled GMD Snake.

[108]

GMD Snake2: the wheel-driven inspection robot. [108]

1997 · Carnegie Mellon University · USA

Dowling’s learning snake

Kevin Dowling’s ten-link robot has 20 servo-driven degrees of freedom. His dissertation joins physical modeling, gait learning and hardware experiments, showing how coordinated body motion can move a wheel-free machine. Replaceable skins and an onboard camera were also investigated.

[118] [119]

The 20-servo, ten-link CMU snake, Figure 6.11. [119]

A two-axis servo link, Figure 6.9. [119]

Physical robot and experimental skins, Figure 6.13. [119]

Onboard camera arrangement, Figure 6.16. [119]

1997 · Mark Setrakian · USA

Snake

Setrakian’s articulated Snake appeared at Robot Wars 1997. A handheld articulated controller, called the WAC, supplied a body shape for the machine to follow through closed-loop servo control. Contemporary event photographs show the robot and controller; the videos capture its unusual movement in the arena.

[130]

Setrakian’s Snake at Robot Wars 1997. Photograph from Team Delta’s event account. [130]

Robot Wars 1997 - Snake Demo

ExperiMENTAL · YouTube

Robot Wars 1997 - Snake vs Scorpion

ExperiMENTAL · YouTube

Robot Wars 1997 Snake vs The Scorpion

Gremlin Co · YouTube

1996 · GMD / Fraunhofer · Germany

GMD Snake

GMD’s first snake used identical plug-together sections, rubber joints and an external power tether. Each section had its own processor and position feedback; a CAN bus coordinated the body. The original page describes configurations of up to 15 sections and a sensor-carrying head.

[107]

GMD Snake: original project photograph. [107]

1994–95 · Laurent Chabin · France

Sniky

Sniky uses nine wagons, eight steering servos and passive wheels to turn a traveling body bend into forward motion. The original specifications give a 790 mm body, 1.27 kg mass and 13 cm/s speed on a smooth surface. An ST62 microcontroller drives the servos and accepts a two-channel radio command.

[114]

Sniky: original construction photograph or design drawing. [114]

Early–mid 1990s · Caltech · USA

Caltech Snakey and spatial joints

Joel Burdick, Gregory Chirikjian and colleagues built hyper-redundant mechanisms and studied how waves of deformation produce locomotion. The 30-degree-of-freedom Snakey uses a variable-geometry truss. Related spatial joint hardware supported work on slender inspection arms. The archive’s picture gallery, gait abstract, modular research and hyper-redundancy pages belong to this research family.

[120] [121] [122] [123]

Caltech: original hyper-redundant robot and joint hardware. [120]

1994–95 · NASA JPL / Caltech · USA

JPL serpentine inspection arm

A slender, internally actuated inspection arm was developed to reach spaces too small for conventional manipulators. The archived page describes an approximately three-foot-long, 1.5-inch-diameter device with a fiber-optic borescope. Its follow-the-tip control guided the rest of the arm through confined openings. Published versions differ in their reported degree-of-freedom count.

[127]

JPL: early serpentine inspection arm. [127]

1990s · Foster-Miller / NASA · USA

Foster-Miller serpentine truss

A lightweight inspection and maintenance arm with an articulated truss structure. Foster-Miller’s original description gives a 14-foot reach and 18 degrees of freedom. Its controller records the insertion path so the arm can retract along the same route around obstacles.

[132]

Foster-Miller serpentine truss: original manufacturer photograph. [132]

Late 1980s · Thomas Lewis / Hughes Aircraft · USA

Hughes R7

R7 places its motors away from the bending axes and transmits motion through low-force, high-speed cables. Local 11:1 reduction drives reduce the cable loads. Coupled differential drives coordinate 16 axes into eight independent degrees of freedom, with a CCD camera at the tip for inspection.

[128]

Hughes R7: original inspection-arm photograph. [128]

R7: inspection-arm motion, clip 1

Original project footage. [137]

R7: inspection-arm motion, clip 2

Original project footage. [138]

R7: inspection-arm motion, clip 3

Original project footage. [139]

1972 onward · Tokyo Institute of Technology / hibot lineage, Japan

Hirose ACM lineage

Shigeo Hirose’s Active Cord Mechanism research established a foundational family of snake robots. ACM III used an articulated body and passive wheels to make ground resistance directional: the body wave supplies propulsion while the wheels roll along the body. Later ACM generations developed three-dimensional and amphibious motion.

[38] [39]