Bimanual regrasping from unimanual machine learning

Abstract — While unimanual regrasping has been studied ex-tensively, either by regrasping in-hand or by placing the object on a surface, bimanual regrasping has seen little attention. The recent popularity of simple end-effectors and dual-manipulator platforms makes bimanual regrasping an important behavior for service robots to possess. We solve the challenge of bimanual regrasping by casting it as an optimization problem, where the objective is to minimize execution time. The optimization problem is supplemented by image processing and a unimanual grasping algorithm based on machine learning that jointly identify two good grasping points on the object and the proper orientations for each end-effector. The optimization algorithm exploits this data by finding the proper regrasp location and orientation to minimize execution time. Influenced by human bimanual manipulation, the algorithm only requires a single stereo image as input. The efficacy of the method we propose is demonstrated on a dual manipulator torso equipped with Barrett WAM arms and Barrett Hands. I

Motion planning for cooperative manipulators folding flexible planar objects

Abstract — Research on robotic manipulation has mostly avoided the grasping of highly deformable objects, although they account for a significant portion of everyday grasping tasks. In this paper we address the problem of using cooperative manipulators for folding tasks of cloth-like deformable objects, from a motion planning perspective. We demonstrate that complex deformable object models are unnecessary for robotic applications. Consequently, a simple object model is exploited to create a new algorithm capable of generating collision-free folding motions for two cooperating manipulators. The algorithm encompasses the essential properties of manipulator-independence, parameterized fold quality, and speed. Numerous experiments executed on a real and simulated dual-manipulator robotic torso demonstrates the method’s effectiveness. I

Non-adjacent dependency learning in humans and other animals

International audienc

Real-time WiFi localization of heterogeneous robot teams using an online random forest

In this paper we present a WiFi-based solution to the localization and mapping problem for teams of heterogeneous robots operating in unknown environments. By exploiting wireless signal strengths broadcast from access points, a robot with a large sensor payload creates a WiFi signal map that can then be shared and utilized for localization by sensor-deprived robots. In our approach, WiFi localization is cast as a classification problem. An online clustering algorithm processes incoming WiFi signals that are then incorporated into an online random forest (ORF). The algorithm’s robustness is increased by a Monte Carlo localization algorithm whose sensor model exploits the results of the ORF classification. The proposed algorithm is shown to run in real-time, allowing the robots to operate in completely unknown environments, where a priori information such as a blue-print or the access points’ location is unavailable. A comprehensive set of experiments not only compares our approach with other algorithms, but also validates the results across different scenarios covering both indoor and outdoor environments

High-sensitivity microsatellite instability assessment for the detection of mismatch repair defects in normal tissue of biallelic germline mismatch repair mutation carriers

Introduction: Lynch syndrome (LS) and constitutional mismatch repair deficiency (CMMRD) are hereditary cancer syndromes associated with mismatch repair (MMR) deficiency. Tumours show microsatellite instability (MSI), also reported at low levels in non-neoplastic tissues. Our aim was to evaluate the performance of high-sensitivity MSI (hs-MSI) assessment for the identification of LS and CMMRD in non-neoplastic tissues. Materials and methods: Blood DNA samples from 131 individuals were grouped into three cohorts: baseline (22 controls), training (11 CMMRD, 48 LS and 15 controls) and validation (18 CMMRD and 18 controls). Custom next generation sequencing panel and bioinformatics pipeline were used to detect insertions and deletions in microsatellite markers. An hs-MSI score was calculated representing the percentage of unstable markers. Results: The hs-MSI score was significantly higher in CMMRD blood samples when compared with controls in the training cohort (p<0.001). This finding was confirmed in the validation set, reaching 100% specificity and sensitivity. Higher hs-MSI scores were detected in biallelic MSH2 carriers (n=5) compared with MSH6 carriers (n=15). The hs-MSI analysis did not detect a difference between LS and control blood samples (p=0.564). Conclusions: The hs-MSI approach is a valuable tool for CMMRD diagnosis, especially in suspected patients harbouring MMR variants of unknown significance or non-detected biallelic germline mutations. Keywords: constitutional mismatch repair deficiency; highly sensitive methodologies; lynch syndrome; microsatellite instability; next generation sequencing

New generation UV-A filters : understanding their photodynamics on a human skin mimic

The sparsity of efficient commercial ultraviolet-A (UV-A) filters is a major challenge toward developing effective broadband sunscreens with minimal human- and eco-toxicity. To combat this, we have designed a new class of Meldrum-based phenolic UV-A filters. We explore the ultrafast photodynamics of coumaryl Meldrum, CMe, and sinapyl Meldrum (SMe), both in an industry-standard emollient and on a synthetic skin mimic, using femtosecond transient electronic and vibrational absorption spectroscopies and computational simulations. Upon photoexcitation to the lowest excited singlet state (S1), these Meldrum-based phenolics undergo fast and efficient nonradiative decay to repopulate the electronic ground state (S0). We propose an initial ultrafast twisted intramolecular charge-transfer mechanism as these systems evolve out of the Franck–Condon region toward an S1/S0 conical intersection, followed by internal conversion to S0 and subsequent vibrational cooling. Importantly, we correlate these findings to their long-term photostability upon irradiation with a solar simulator and conclude that these molecules surpass the basic requirements of an industry-standard UV filter

Rationale and design of the HIP fracture Accelerated surgical TreaTment And Care tracK (HIP ATTACK) Trial : a protocol for an international randomised controlled trial evaluating early surgery for hip fracture patients

© Author(s) (or their employer(s)) 2019. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.Peer reviewedPublisher PD

CALYPSO 2019 Cruise Report: field campaign in the Mediterranean

This cruise aimed to identify transport pathways from the surface into the interior ocean during the late winter in the Alborán sea between the Strait of Gibraltar (5°40’W) and the prime meridian. Theory and previous observations indicated that these pathways likely originated at strong fronts, such as the one that separates salty Mediterranean water and the fresher water in owing from the Atlantic. Our goal was to map such pathways and quantify their transport. Since the outcropping isopycnals at the front extend to the deepest depths during the late winter, we planned the cruise at the end of the Spring, prior to the onset of thermal stratification of the surface mixed layer.Funding was provided by the Office of Naval Research under Contract No. N000141613130