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Hands in the Real World
Robots face a rapidly expanding range of potential applications beyond controlled environments, from remote exploration and search-and-rescue to household assistance and agriculture. The focus of physical interaction is typically delegated to end-effectors -- fixtures, grippers or hands -- as these machines perform manual tasks. Yet, effective deployment of versatile robot hands in the real world is still limited to few examples, despite decades of dedicated research. In this paper we review hands that found application in the field, aiming to discuss open challenges with more articulated designs, discussing novel trends and perspectives. We hope to encourage swift development of capable robotic hands for long-term use in varied real world settings. The first part of the paper centers around progress in artificial hand design, identifying key functions for a variety of environments. The final part focuses on the overall trends in hand mechanics, sensors and control, and how performance and resiliency are qualified for real world deployment
Haptic search with the Smart Suction Cup on adversarial objects
Suction cups are an important gripper type in industrial robot applications,
and prior literature focuses on using vision-based planners to improve grasping
success in these tasks. Vision-based planners can fail due to adversarial
objects or lose generalizability for unseen scenarios, without retraining
learned algorithms. We propose haptic exploration to improve suction cup
grasping when visual grasp planners fail. We present the Smart Suction Cup, an
end-effector that utilizes internal flow measurements for tactile sensing. We
show that model-based haptic search methods, guided by these flow measurements,
improve grasping success by up to 2.5x as compared with using only a vision
planner during a bin-picking task. In characterizing the Smart Suction Cup on
both geometric edges and curves, we find that flow rate can accurately predict
the ideal motion direction even with large postural errors. The Smart Suction
Cup includes no electronics on the cup itself, such that the design is easy to
fabricate and haptic exploration does not damage the sensor. This work
motivates the use of suction cups with autonomous haptic search capabilities in
especially adversarial scenarios
Tenodesis Grasp Emulator: Kinematic Assessment of Wrist-Driven Orthotic Control
Wrist-driven orthotics have been designed to assist people with C6-7 spinal
cord injury, however, the kinematic constraint imposed by such a control
strategy can impede mobility and lead to abnormal body motion. This study
characterizes body compensation using the novel Tenodesis Grasp Emulator, an
adaptor orthotic that allows for the investigation of tenodesis grasping in
subjects with unimpaired hand function. Subjects perform a series of
grasp-and-release tasks in order to compare normal (test control) and
constrained wrist-driven modes, showing significant compensation as a result of
the constraint. A motor-augmented mode is also compared against traditional
wrist-driven operation, to explore the potential role of hybrid human-robot
control. We find that both the passive wrist-driven and motor-augmented modes
fulfill different roles throughout various tasks tested. Thus, we conclude that
a flexible control scheme that can alter intervention based on the task at hand
holds the potential to reduce compensation in future work.Comment: 7 pages, 11 figures, submitted to International Conference on
Robotics and Automation (ICRA) 2022. Video Supplement:
https://youtu.be/NIgKg5R3Ro
Physical vapour deposition of thin films for use in superconducting RF cavities
The production of superconducting coatings for radio
frequency cavities is a rapidly developing field that
should ultimately lead to acceleration gradients greater
than those obtained by bulk Nb RF cavities. Optimizing
superconducting properties of Nb thin-films is therefore
essential. Nb films were deposited by magnetron
sputtering in pulsed DC mode onto Si (100) and MgO
(100) substrates and also by high impulse magnetron
sputtering (HiPIMS) onto Si (100), MgO (100) and
polycrystalline Cu. The films were characterised using
scanning electron microscopy, x-ray diffraction and DC
SQUID magnetometry
Development of thin films for superconducting RF cavities
Superconducting coatings for superconducting radio frequency (SRF) cavities is an intensively developing field that should ultimately lead to acceleration gradients better than those obtained by bulk Nb RF cavities. ASTeC has built and developed experimental systems for superconducting thin-film deposition, surface analysis and measurement of Residual Resistivity Ratio (RRR). Nb thin-films were deposited by magnetron sputtering in DC or pulsed DC mode (100 to 350 kHz with 50% duty cycle) with powers ranging from 100 to 600 W at various temperatures ranging from room temperature to 800 °C on Si (100) substrates. The first results gave RRR in the range from 2 to 22 with a critical temperature Tc ≈ 9.5 K. Scanning electron microscopy (SEM), x-ray diffraction (XRD), electron back scattering diffraction (EBSD) and DC SQUID magnetometry revealed significant correlations between the film structure, morphology and superconducting properties
High power impulse magnetron sputtering of thin films for superconducting RF cavities
The production of superconducting coatings for radio
frequency cavities is a rapidly developing field that
should ultimately lead to acceleration gradients greater
than those obtained by bulk Nb RF cavities. The use of
thin films made from superconductors with
thermodynamic critical field, Hc>Hn/cb, allows the
possibility of multilayer superconductor – insulator –
superconductor (SIS) films and also accelerators that
could operate at temperatures above the 2 K typically
used. SIS films theoretically allow increased acceleration
gradient due to magnetic shielding of underlying
superconducting layers [1] and higher operating
temperature can reduce cost [2]. High impulse magnetron
sputtering (HiPIMS) and pulsed DC magnetron sputtering
processes were used to deposit NbN and NbTiN thin films
onto Si(100) substrate. The films were characterised using
scanning electron microscopy (SEM), x-ray diffraction
(XRD), Rutherford back-scattering spectroscopy (RBS)
and a four point probe
Physical vapour deposition of NbTiN thin films for superconducting RF cavities.
The production of superconducting coatings for radio frequency (RF) cavities is a rapidly developing field that should ultimately lead to acceleration gradients greater than those obtained by bulk Nb RF cavities. The use of thin
films made from superconductors with thermodynamic critical field, Hc > HC(Nb), allows the possibility of multilayer superconductor – insulator – superconductor (SIS) films and accelerators that could operate at temperatures above 2 K. SIS films theoretically allow increased acceleration gradient due to magnetic shielding
of underlying superconducting layers [1] and higher operating temperature can reduce cost [2]. High impulse magnetron sputtering (HiPIMS) and pulsed DC magnetron sputtering processes were used to deposit NbTiN thin films onto Si(100) substrate. The films were characterised using scanning electron microscopy (SEM), x-ray diffraction (XRD), Rutherford back-scattering spectroscopy (RBS)
and a four-point probe
Endemicity of Zoonotic Diseases in Pigs and Humans in Lowland and Upland Lao PDR: Identification of Socio-cultural Risk Factors
In Lao People's Democratic Republic pigs are kept in close contact with families. Human risk of infection with pig zoonoses arises from direct contact and consumption of unsafe pig products. This cross-sectional study was conducted in Luang Prabang (north) and Savannakhet (central-south) Provinces. A total of 59 villages, 895 humans and 647 pigs were sampled and serologically tested for zoonotic pathogens including: hepatitis E virus (HEV), Japanese encephalitis virus (JEV) and Trichinella spiralis; In addition, human sera were tested for Taenia spp. and cysticercosis. Seroprevalence of zoonotic pathogens in humans was high for HEV (Luang Prabang: 48.6%, Savannakhet: 77.7%) and T. spiralis (Luang Prabang: 59.0%, Savannakhet: 40.5%), and lower for JEV (around 5%), Taenia spp. (around 3%) and cysticercosis (Luang Prabang: 6.1, Savannakhet 1.5%). Multiple correspondence analysis and hierarchical clustering of principal components was performed on descriptive data of human hygiene practices, contact with pigs and consumption of pork products. Three clusters were identified: Cluster 1 had low pig contact and good hygiene practices, but had higher risk of T. spiralis. Most people in cluster 2 were involved in pig slaughter (83.7%), handled raw meat or offal (99.4%) and consumed raw pigs' blood (76.4%). Compared to cluster 1, cluster 2 had increased odds of testing seropositive for HEV and JEV. Cluster 3 had the lowest sanitation access and had the highest risk of HEV, cysticercosis and Taenia spp. Farmers which kept their pigs tethered (as opposed to penned) and disposed of manure in water sources had 0.85 (95% CI: 0.18 to 0.91) and 2.39 (95% CI: 1.07 to 5.34) times the odds of having pigs test seropositive for HEV, respectively. The results have been used to identify entry-points for intervention and management strategies to reduce disease exposure in humans and pigs, informing control activities in a cysticercosis hyper-endemic village
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