363 research outputs found
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Chip-on-tip endoscope incorporating a soft robotic pneumatic bending microactuator.
In the ever advancing field of minimally invasive surgery, flexible instruments with local degrees of freedom are needed to navigate through the intricate topologies of the human body. Although cable or concentric tube driven solutions have proven their merits in this field, they are inadequate for realizing small bending radii and suffer from friction, which is detrimental when automation is envisioned. Soft robotic actuators with locally actuated degrees of freedom are foreseen to fill in this void, where elastic inflatable actuators are very promising due to their S3-principle, being Small, Soft and Safe. This paper reports on the characterization of a chip-on-tip endoscope, consisting out of a soft robotic pneumatic bending microactuator equipped with a 1.1 × 1.1 mm2 CMOS camera. As such, the total diameter of the endoscope measures 1.66 mm. To show the feasibility of using this system in a surgical environment, a preliminary test on an eye mock-up is conducted
State of Utah v. Jose Javala-Perez : Brief of Appellee
An appeal from convictions for one count of Driving Under the Influence, a Class B Misdemeanor, one count of Speeding, a Class C Misdemeanor, one count of Faulty Equipment, a Class C Misdemeanor, in the Third District Court, Salt Lake County, the Honorable William W. Barrett, presiding
Characterisation of Tactile Sensors based on Fibre Bragg gratings Towards Temperature Independent Pressure Sensing
AbstractThis paper presents the development of flexible pressure sensing sheets, based on fibre Bragg grating sensing elements. The devices feature optical wavelength-encoded sensing signals and show promise in applications such as pressure mapping and tactile sensing. FBGs inscribed in highly-birefringent microstructured fibres, reflecting two separate Bragg peaks, are specially employed. Prototypes with FBGs embedded in polymer sheets were produced and characterised for temperature and pressure sensitivities. An improved sensor structure was implemented aiming at temperature independent tactile sensing with Bragg peak separation as the sensing signal
Embedding of fibre optic sensors within flexible host
This work deals with the establishment of a UV polymerisation procedure combined with moulding technology towards the development of a mass production technology for the fabrication of flexible polymers with optical fibres embedded. The concept is to provide an artificial sensing skin based on fibre optic sensors which can be applied to irregular or moveable surfaces for distributed pressure applications, as for instance in structural monitoring or rehabilitation. The selected polymers for such an application are here reviewed and their composition adjusted in order to accommodate the required flexibility. As compared to other techniques, UV polymerisation advantages are pointed out when moving towards industrial applications and large scale productions. Meanwhile, curing tests to embed optical fibres in the developed polymers are carried out with an in house developed glass mould set-up and the results are presented. Laser ablation of polymers is also discussed in order to reply the demand of complex fibre layout as for example meandering or curved shape patterns
Morphological Control of Cilia-Inspired Asymmetric Movements Using Nonlinear Soft Inflatable Actuators.
Soft robotic systems typically follow conventional control schemes, where actuators are supplied with dedicated inputs that are regulated through software. However, in recent years an alternative trend is being explored, where the control architecture can be simplified by harnessing the passive mechanical characteristics of the soft robotic system. This approach is named "morphological control", and it can be used to decrease the number of components (tubing, valves and regulators) required by the controller. In this paper, we demonstrate morphological control of bio-inspired asymmetric motions for systems of soft bending actuators that are interconnected with passive flow restrictors. We introduce bending actuators consisting out of a cylindrical latex balloon in a flexible PVC shell. By tuning the radii of the tube and the shell, we obtain a nonlinear relation between internal pressure and volume in the actuator with a peak and valley in pressure. Because of the nonlinear characteristics of the actuators, they can be assembled in a system with a single pressure input where they bend in a discrete, preprogrammed sequence. We design and analyze two such systems inspired by the asymmetric movements of biological cilia. The first replicates the swept area of individual cilia, having a different forward and backward stroke, and the second generates a travelling wave across an array of cilia
Изучение микробиологической стабильности геля кальция глюконата 2,5%
ГЕЛИКАЛЬЦИЯ ГЛЮКОНАТМИКРОБИОЛОГИ
Dynamic Characterization of Rubber O-Rings: Squeeze and Size Effects
This paper concerns the dynamic characterization of rubber O-rings used to introduce damping in high speed gas bearing systems. O-shaped rubber rings composed of high temperature rubber compounds are characterized in terms of stiffness and damping coefficients in the frequency range 100–800 Hz. Simple formulas with frequency independent coefficients were identified to express the viscoelastic properties of the O-rings. The formulas proposed approximate the stiffness and damping coefficients of O-rings of general size
Between informal and formal politics : neopatrimonialism and party development in post-Soviet Kazakhstan
This study is concerned with exploring the relationship between informal forms of political behaviour and relations and the development of formal institutions in post Soviet Central Asian states as a way to explain the development of authoritarianism in the region. It moves the debate on from current scholarship which places primacy on either formal or informal politics in explaining modem political development in Central Asia, by examining the relationship between the two. It utilises Kazakhstan as a case study by assessing how the neopatrimonial system evident in the country has influenced and shaped the development of political parties. It investigates how personalism of political office, patronage and patron-client networks and factional elite conflict have influenced and shaped the institutional constraints affecting party development (institutional choice, electoral design and party law), the type of parties emerging (organisation, ideology and membership) and parties' relationship with society.EThOS - Electronic Theses Online ServiceGBUnited Kingdo
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