A hyper-redundant manipulator

“Hyper-redundant” manipulators have a very large number of actuatable degrees of freedom. The benefits of hyper-redundant robots include the ability to avoid obstacles, increased robustness with respect to mechanical failure, and the ability to perform new forms of robot locomotion and grasping. The authors examine hyper-redundant manipulator design criteria and the physical implementation of one particular design: a variable geometry truss

Zoomorphic extended body

My thesis work is built around emerging technologies within the fields of prosthetic and robotics. The end result is a speculative proposal with how to expand the potential modes of use with these emerging technologies to extend and build upon their potential uses

The kinematics of hyper-redundant robot locomotion

This paper considers the kinematics of hyper-redundant (or “serpentine”) robot locomotion over uneven solid terrain, and presents algorithms to implement a variety of “gaits”. The analysis and algorithms are based on a continuous backbone curve model which captures the robot's macroscopic geometry. Two classes of gaits, based on stationary waves and traveling waves of mechanism deformation, are introduced for hyper-redundant robots of both constant and variable length. We also illustrate how the locomotion algorithms can be used to plan the manipulation of objects which are grasped in a tentacle-like manner. Several of these gaits and the manipulation algorithm have been implemented on a 30 degree-of-freedom hyper-redundant robot. Experimental results are presented to demonstrate and validate these concepts and our modeling assumptions

Computational Modeling and Experimental Characterization of Pneumatically Driven Actuators for the Development of a Soft Robotic Arm

abstract: Soft Poly-Limb (SPL) is a pneumatically driven, wearable, soft continuum robotic arm designed to aid humans with medical conditions, such as cerebral palsy, paraplegia, cervical spondylotic myelopathy, perform activities of daily living. To support user's tasks, the SPL acts as an additional limb extending from the human body which can be controlled to perform safe and compliant mobile manipulation in three-dimensional space. The SPL is inspired by invertebrate limbs, such as the elephant trunk and the arms of the octopus. In this work, various geometrical and physical parameters of the SPL are identified, and behavior of the actuators that comprise it are studied by varying their parameters through novel quasi-static computational models. As a result, this study provides a set of engineering design rules to create soft actuators for continuum soft robotic arms by understanding how varying parameters affect the actuator's motion as a function of the input pressure. A prototype of the SPL is fabricated to analyze the accuracy of these computational models by performing linear expansion, bending and arbitrary pose tests. Furthermore, combinations of the parameters based on the application of the SPL are determined to affect the weight, payload capacity, and stiffness of the arm. Experimental results demonstrate the accuracy of the proposed computational models and help in understanding the behavior of soft compliant actuators. Finally, based on the set functional requirements for the assistance of impaired users, results show the effectiveness of the SPL in performing tasks for activities of daily living.Dissertation/ThesisMasters Thesis Mechanical Engineering 201

Soft-Tentacle Gripper for Pipe Crawling to Inspect Industrial Facilities Using UAVs

This paper presents a crawling mechanism using a soft-tentacle gripper integrated into an unmanned aerial vehicle for pipe inspection in industrial environments. The objective was to allow the aerial robot to perch and crawl along the pipe, minimizing the energy consumption, and allowing to perform contact inspection. This paper introduces the design of the soft limbs of the gripper and also the internal mechanism that allows movement along pipes. Several tests have been carried out to ensure the grasping capability on the pipe and the performance and reliability of the developed system. This paper shows the complete development of the system using additive manufacturing techniques and includes the results of experiments performed in realistic environments.Unión Europea SI-1762/23/201

Sequence-specific detection of different strains of LCMV in a single sample using tentacle probes

abstract: Background Virus infections often result in quasispecies of viral strains that can have dramatic impacts on disease outcomes. However, sequencing of viruses to determine strain composition is time consuming and often cost-prohibitive. Rapid, cost-effective methods are needed for accurate measurement of virus diversity to understand virus evolution and can be useful for experimental systems. Methods We have developed a novel molecular method for sequence-specific detection of RNA virus genetic variants called Tentacle Probes. The probes are modified molecular beacons that have dramatically improved false positive rates and specificity in routine qPCR. To validate this approach, we have designed Tentacle Probes for two different strains of Lymphocytic Choriomeningitis Virus (LCMV) that differ by only 3 nucleotide substitutions, the parental Armstrong and the more virulent Clone-13 strain. One of these mutations is a missense mutation in the receptor protein GP1 that leads to the Armstrong strain to cause an acute infection and Clone-13 to cause a chronic infection instead. The probes were designed using thermodynamic calculations for hybridization between target or non-target sequences and the probe. Results Using this approach, we were able to distinguish these two strains of LCMV individually by a single nucleotide mutation. The assay showed high reproducibility among different concentrations of viral cDNA, as well as high specificity and sensitivity, especially for the Clone-13 Tentacle Probe. Furthermore, in virus mixing experiments we were able to detect less than 10% of Clone-13 cDNA diluted in Armstrong cDNA. Conclusions Thus, we have developed a fast, cost-effective approach for identifying Clone-13 strain in a mix of other LCMV strains.The electronic version of this article is the complete one and can be found online at: https://virologyj.biomedcentral.com/articles/10.1186/s12985-017-0863-

Kinematics and Hydrodynamics of Cephalopod Turning Performance in Routine Swimming and Predatory Attacks

Steady rectilinear swimming has received considerable attention in aquatic animal locomotion studies. Unsteady swimming movements, however, represent a large portion of many aquatic animals’ locomotive repertoire and have not been examined extensively. This study incorporates kinematic analyses of routine turning performance of brief squid Lolliguncula brevis and dwarf cuttlefish Sepia bandensis (Chapter 2), 3D velocimetry techniques to examine hydrodynamic turning performance of L. brevis (Chapter 3) and kinematic analyses of turning performance of L. brevis during predatory attacks on shrimp and fish prey (Chapter 4). Both L. brevis and S. bandensis demonstrated high maneuverability, having the lowest measures of length-specific turning radii reported to date for any aquatic taxa. Lolliguncula brevis was more agile than S. bandensis, i.e., L. brevis exhibited higher angular velocities during turning. In L. brevis, jet flows were the principle driver of angular velocity. Asymmetric fin motions played a reduced role in turning, and arm wrapping increased turning performance to varying degrees depending on the species. Flow patterns and relative torque contributions from the fins and jet varied with the speed of oncoming flow and orientation of the squid. Four turning categories were identified: (1) short tail-first turns, (2) long tail-first turns, (3) vertically oriented turns and (4) arms-first turns. The jet generally contributed more to turning torque than the fins in short tail-first, long tail-first and vertical turns. However, the fins produced a wider repertoire of flows, including isolated vortex rings, linked vortices and regions of elongated tubular vorticity, and were more important than the jet for turning torque generation during arms-first turns. Both the jet and fins produced torque contributing to roll and pitch, but the relative importance of these flows differed by turning category, with jet roll/pitch stabilization being critical for short tail-first turns and fin roll/pitch stabilization being integral to arms-first and vertical turns. Squid attack sequences involved three phases: (1) approach, (2) strike and (3) recoil. Lolliguncula brevis employed different attack strategies for fish and shrimp and turning performance played a significant role during predatory encounters. The squid exhibited high agility during the approach for both prey types. However, positioning, maneuverability and synchronized fin motions were more important for attacks on shrimp than fish. For attacks on fish, squid favored maximizing linear attack speeds over high maneuverability. Squid controlled their translational velocity and tentacle extension velocity during the strike, and demonstrated considerable rotational control during the recoil phase despite prey escape attempts. This study represents the most comprehensive quantitative turning performance study of cephalopods to date and demonstrates that the unique body architecture of these taxa provides exceptional advantages for maneuvering in the marine environment

Creating Procedural Animation for the Terrestrial Locomotion of Tentacled Digital Creatures

This thesis presents a prototype system to develop procedural animation for the goal-directed terrestrial locomotion of tentacled digital creatures. Creating locomotion for characters with multiple highly deformable limbs is time and labor intensive. This prototype system presents an interactive real-time physically-based solution to procedurally create tentacled creatures and simulate their goal-directed movement about an environment. Artistic control over both the motion path of the creature and the localized behavior of the tentacles is maintained. This system functions as a stand-alone simulation and a tool has been created to integrate it into production software. Applications include use in visual effects and animation where generalized behavior of tentacled creatures is required

Dynamic Capture Using a Traplike Soft Gripper With Stiffness Anisotropy

Dynamic capture is a common skill that humans have practiced extensively but is a challenging task for robots in which sensing, planning, and actuation must be tightly coordinated to deal with targets of diverse shapes, sizes, and velocity. In particular, the impact force may cause serious damage to a rigid gripper and even its carrier, e.g., a robotic arm. Existing soft grippers suffer from low speed and force to actively respond to capturing dynamic targets. In this article, we propose a soft gripper capable of efficient capture of dynamic targets, taking inspiration from the biological structures of multitentacled animals or plants. The presented gripper uses a cluster of tentacles to achieve an omnidirectional envelope and high tolerance to dynamic target during the capturing process. In addition, a stiffness anisotropy property is implemented to the tentacle structure to form a “trap” making it easy for the targets to enter yet difficult to escape. We also present an analytical model for the tentacle structure to describe its deformation during the collision with a target. In experiments, we construct a robotic prototype and demonstrate its ability to capture dynamic targets

Advanced Strategies for Robot Manipulators

Amongst the robotic systems, robot manipulators have proven themselves to be of increasing importance and are widely adopted to substitute for human in repetitive and/or hazardous tasks. Modern manipulators are designed complicatedly and need to do more precise, crucial and critical tasks. So, the simple traditional control methods cannot be efficient, and advanced control strategies with considering special constraints are needed to establish. In spite of the fact that groundbreaking researches have been carried out in this realm until now, there are still many novel aspects which have to be explored