Subsea crab bounding gait of leg-paddle hybrid driven shoal crablike robot

Wang, Gang; Chen, Xi; Yang, Shengxi; Jia, Peng; Yan, Xingya; Xie, Jiang

doi:10.1016/j.mechatronics.2017.10.002

Cited by 26 publications

(12 citation statements)

References 12 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Other legged robots have shown lower COT. For example, Shoal Legged Robot (mass 4 kg) has a walking COT of 3.7 in water [14], and Titan-XIII (mass 5.75 kg) has a walking COT of 1.76 on grass [47], suggesting that mechanical improvements and gait optimization could reduce COT perhaps by orders of magnitude. Others have shown qualitative differences between dynamic gaits as speed increases in granular media [39].…”

Section: Conclusion and Discussionmentioning

confidence: 99%

“…Larger-scale autonomous legged underwater vehicles Ursula and Ariel have been developed for mine hunting in the surfzone [13]. The design of a leg-paddle-hybriddriven robot and bounding gait inspired by swimming crabs was presented in [14]. Chinese mitten crabs inspired Zhang et al to develop a compliant crablike robot with an adaptive crab-inspired gait [15].…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Get a grip: inward dactyl motions improve efficiency of sideways-walking gait for an amphibious crab-like robot

2022

View full text Add to dashboard Cite

Crabs are adept at traversing natural terrains that are challenging for mobile robots. Curved dactyls are a characteristic feature to engage terrain for resisting wave forces in surf zones. Inward gripping motions at the onset of stance could increase stability.Here, we add inward gripping motions to the foot trajectories of walking gaits to determine the energetic costs and speed for our 12 DOF crab-like robot, Sebastian. Specifically, we compared two gaits in which the step size (stance length) was the same, but the swing trajectories were either triangular (to minimize trajectory length) or quadrilateral (in which the leg deliberately oversteps in order to perform a distributed inward grip (DIG). The resulting gripping quadrilateral gait significantly outperformed the non-gripping triangular gait on diverse terrains (hard linoleum, soft mats, and underwater sand), providing between 15% and 34% energy savings. Using this gait eliminates the advantage of spherical end effectors for slip reduction on hard linoleum, which may lead to a better understanding of how to use crab-like morphology for more efficient locomotion. Finally, we subjected the walking robot to lab-generated waves with wave height approximately 166% of the dactyl length. Both gaits enabled the robot to walk undisturbed by the waves. Taken together, these results suggest that impact trajectory will be key for future amphibious robots. Future work can provide deeper understanding of the relationships between dactyls, gaits, and substrates in biology and robots.

show abstract

Section: Conclusion and Discussionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Get a grip: inward dactyl motions improve efficiency of sideways-walking gait for an amphibious crab-like robot

2022

View full text Add to dashboard Cite

show abstract

“…This robot exhibits superior performance on relative motion speed compared with other typical amphibious robots. [2,10,12,14,[39][40][41][42][43][44][45][46][47][48][49][50][51][52][53][54][55][56][57][58] In particular, the relative terrestrial speed reaches to ≈10.9 BL s -1 , which shows the significant superiority of this design. The relative aquatic speed is ≈2.3 BL s -1 , which is not that fast as the terrestrial speed, but still better than most amphibious robots.…”

Section: Conclusion and Discussionmentioning

confidence: 99%

Miniature Amphibious Robot Actuated by Rigid‐Flexible Hybrid Vibration Modules

et al. 2022

View full text Add to dashboard Cite

Amphibious robots can undertake various tasks in terrestrial and aquatic environments for their superior environmental compatibility. However, the existing amphibious robots usually utilize multi-locomotion systems with transmission mechanisms, leading to complex and bulky structures. Here, a miniature amphibious robot based on vibration-driven locomotion mechanism is developed. The robot has two unique rigid-flexible hybrid modules (RFH-modules), in which a soft foot and a flexible fin are arranged on a rigid leg to conduct vibrations from an eccentric motor to the environment. Then, it can run on ground with the soft foot adopting the friction locomotion mechanism and swim on water with the flexible fin utilizing the vibration-induced flow mechanism. The robot is untethered with a compact size of 75 × 95 × 21 mm 3 and a small weight of 35 g owing to no transmission mechanism or joints. It realizes the maximum speed of 815 mm s -1 on ground and 171 mm s -1 on water. The robot, actuated by the RFH-modules based on vibration-driven locomotion mechanism, exhibits the merits of miniature structure and fast movements, indicating its great potential for applications in narrow amphibious environments.

show abstract

“…Finally, a number of researchers have taken into account the direct interaction of underwater vehicles with the seabed by mean of different kinds of limbs (Akizono et al, 1997; Greiner et al, 1996; Jun et al, 2015; Wang et al, 2017). More recent work envisions dynamic legged locomotion (jumping (Wang et al, 2017), hopping (Picardi et al, 2018), and others (Arienti et al, 2013)) as a profitable direction toward the improvement of such kind of locomotion. It appears pivotal to investigate such gaits with respect to the common task of sample collections, which can lead to an increase of the overall weight of the robot.…”

Section: Discussionmentioning

confidence: 99%

Morphologically induced stability on an underwater legged robot with a deformable body

Picardi

Hauser

Laschi

2019

The International Journal of Robotics Research

View full text Add to dashboard Cite

For robots to navigate successfully in the real-world, unstructured environment adaptability is a prerequisite. While this is typically implemented within the control layer, there have been recent proposals of adaptation through a morphing of the body. However, the successful demonstration of this approach has mostly been theoretical and in simulations thus far. In this work we present an underwater hopping robot that features a deformable body implemented as a deployable structure which is covered by a soft skin for which it is possible to manually change the body size without altering any other property (e.g. buoyancy or weight). For such a system, we show that it is possible to induce a stable hopping behaviour instead of a fall, by just increasing the body size. We provide a mathematical model that describes the hopping behaviour of the robot under the influence of shape-dependent underwater contributions (drag, buoyancy and added mass) in order to analyse and compare the results obtained. Moreover, we show that for certain conditions, a stable hopping behaviour can only be obtained through changing the morphology of the robot as the controller (i.e. actuator) would already be working at maximum capacity. The presented work demonstrates that, through the exploitation of shape-dependent forces, the dynamics of a system can be modified through altering the morphology of the body to induce a desirable behaviour and, thus, a morphological change can be an effective alternative to the classic control. Prepared using sagej.cls [Version: 2017/01/17 v1.20] * This is consistent with the framework suggested by Füchslin et al. (2013) Prepared using sagej.cls

show abstract

Subsea crab bounding gait of leg-paddle hybrid driven shoal crablike robot

Cited by 26 publications

References 12 publications

Get a grip: inward dactyl motions improve efficiency of sideways-walking gait for an amphibious crab-like robot

Get a grip: inward dactyl motions improve efficiency of sideways-walking gait for an amphibious crab-like robot

Miniature Amphibious Robot Actuated by Rigid‐Flexible Hybrid Vibration Modules

Morphologically induced stability on an underwater legged robot with a deformable body

Contact Info

Product

Resources

About