A Novel Pneumatic Soft Snake Robot Using Traveling-Wave Locomotion in Constrained Environments

Qi, Xinda; Shi, Hongyang; Pinto, Thassyo; Tan, Xiaobo

doi:10.1109/lra.2020.2969923

Cited by 61 publications

(20 citation statements)

References 18 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…[ 10,11 ] They also show increased safety and dexterity can be lightweight and used within constrained environments with restricted access. [ 12,13 ] Many soft robots have a biologically inspired design coming from snakes, [ 14–17 ] worms, [ 18–20 ] fishes, [ 21–24 ] manta rays, [ 25,26 ] and tentacles. [ 27–29 ] The scope of applications includes minimally invasive surgery, [ 30,31 ] rehabilitation, [ 32,33 ] elderly assistance, [ 34 ] safe human–robot interaction, [ 35,36 ] and handling of fragile materials.…”

Section: Introductionmentioning

confidence: 99%

Finite Element Modeling of Soft Fluidic Actuators: Overview and Recent Developments

Xavier

Fleming

Yong

2020

Advanced Intelligent Systems

169

View full text Add to dashboard Cite

Soft robotics has experienced an exponential growth in publications in the last two decades. [1] Unlike rigid conventional manipulators, [2,3] soft robots based on hydrogels, [4,5] electroactive polymers, [6,7] and elastomers [7-9] are physically resilient and can adapt to delicate objects and environments due to their conformal deformation. [10,11] They also show increased safety and dexterity can be lightweight and used within constrained environments with restricted access. [12,13] Many soft robots have a biologically inspired design coming from snakes, [14-17] worms, [18-20] fishes, [21-24] manta rays, [25,26] and tentacles. [27-29] The scope of applications includes minimally invasive surgery, [30,31] rehabilitation, [32,33] elderly assistance, [34] safe human-robot interaction, [35,36] and handling of fragile materials. [37,38] Important features of soft robotics design, fabrication, modeling, and control are covered in the soft robotics toolkit. [39,40] The building blocks of soft robots are the soft actuators. The most popular category of soft actuator is the soft fluidic actuator (SFA), where actuation is achieved using hydraulics or pneumatics. [8,41] These actuators are usually fabricated with silicone rubbers following a 3D molding process, [42] although directly 3D printing the soft actuators is also possible. [43,44] Silicone rubber is a highly flexible/extensible elastomer with high-temperature resistance, lowtemperature flexibility, and good biocompatibility. [45] Elastomers can withstand very large strains over 500% with no permanent deformation or fracture. [46] For relatively small strains, simple linear stress-strain relationships can be used, and two of the following parameters can be used to describe the elastic properties: bulk compressibility, shear modulus, tensile modulus (Young's modulus of elasticity), or Poisson's ratio. [45] For large deformations, nonlinear solid mechanic models using hyperelasticity should be considered. [8,32,47-50] Due to the strong nonlinearities in SFAs and their complex geometries, analytical modeling is challenging. [51] A brief review of the analytical methods for modeling of soft robotic structures is provided in the following. 1.1. Analytical Modeling of Soft Actuators The majority of soft/continuum robots with bending motion can be approximated as a series of mutually tangent constant curvature sections, i.e., piecewise constant curvature. [52] This is a result of the fact that the internal potential energy is uniformly distributed along each section for pressure-driven robots. [53] This approach has also been validated using Hamilton's principle by Gravagne et al. [54] As discussed by Webster and Jones, [52] the kinematics of continuum robots can be separated into robotspecific and robot-independent components in this approach. The robot specific mapping transforms the input pressures P or actuator space q to the configuration space κ, ϕ, l, and the robot-independent mapping goes from the configuration space to the task space x. The actuator space contai...

show abstract

Section: Introductionmentioning

confidence: 99%

Finite Element Modeling of Soft Fluidic Actuators: Overview and Recent Developments

Xavier

Fleming

Yong

2020

Advanced Intelligent Systems

169

View full text Add to dashboard Cite

show abstract

“…Another common usage is for matter transport, for example peristaltic waves within the human digestive system to transport waste or ciliated epithelial cells which transport mucus. Because of this biological precedent many efforts have gone into making travelling wave mechanisms in robots, particularly within the soft or bio-inspired robotics fields [1] [2] [3] [4].…”

Section: Introductionmentioning

confidence: 99%

Free Tendons for Travelling Wave generation in Elastomer Membranes

Wharton

Bloomfield-Gadêlha

Conn

2021

2021 IEEE 4th International Conference on Soft Robotics (RoboSoft)

View full text Add to dashboard Cite

A novel method for the generation of travelling waves in soft robots is presented. Here a soft elastomer membrane is embedded with freely sliding nylon tendons. Instead of being anchored to a point on the membrane, these tendons transmit force via friction generated by sliding within the interior of the membrane. This system can produce continuous travelling waves with amplitudes of 27-45mm at wave speeds of up to 23mm/s, using only a single actuator to apply tension to the tendons. The travelling waves were able to move granular material (poppy seeds) as well as a 147g apple. Experimental results demonstrate that the wave progresses through three phases; the initial static phase, followed by the travelling wave phase and finally the (end of travel) blocked phase, with curvature increasing and wave amplitude decreasing across the travelling and blocked phases. This represents wave degradation in which the membrane compresses relative to the tendon, though this did not limit wave travel over the displacements tested. The wave speeds produced were an order of magnitude higher than tendon winding speed suggesting the system acts with natural gearing. This mechanism shows promise for applications in matter transport of unstructured or soft objects and the principle could also be applied to locomoting robots as the low amount of actuators and degrees of control would reduce the complexity and bulkiness of the robots.

show abstract

“…Similar to previous cases, the three tubes are pressurized sequentially, generating transverse traveling wave motion and crawl on the surface. Another relevant work by Qi et al 33 exhibited a 3D printed modular robot, designed using finite element software, that uses four types of similar modules that differ only by their internal air pathways. Thus, modules can be assembled serially and controlled by four inlets to form approximated traveling wave motion regardless of the number of modules.…”

Section: Introductionmentioning

confidence: 99%

Fluid-driven traveling waves in soft robots

Salem¹,

Gat²,

Or³

2021

Preprint

View full text Add to dashboard Cite

Many marine creatures, gastropods, and earthworms generate continuous traveling waves in their bodies for locomotion within marine environments, complex surfaces, and inside narrow gaps. In this work, we study theoretically and experimentally the use of embedded pneumatic networks as a mechanism to mimic nature and generate bi-directional traveling waves in soft robots. We apply long-wave approximation to theoretically calculate the required distribution of pneumatic network and inlet pressure oscillations needed to create desired moving wave patterns. We then fabricate soft robots with internal pneumatic network geometry based on these analytical results. The experimental results agree well with our model and demonstrate the propagation of moving waves in soft robots, along with locomotion capabilities. The presented results allow fabricating soft robots capable of continuous moving waves via the common approach of embedded pneumatic networks and requiring only two input controls.

show abstract

A Novel Pneumatic Soft Snake Robot Using Traveling-Wave Locomotion in Constrained Environments

Cited by 61 publications

References 18 publications

Finite Element Modeling of Soft Fluidic Actuators: Overview and Recent Developments

Finite Element Modeling of Soft Fluidic Actuators: Overview and Recent Developments

Free Tendons for Travelling Wave generation in Elastomer Membranes

Fluid-driven traveling waves in soft robots

Contact Info

Product

Resources

About