Planetary rover technology development requirements

Planetary surface (including lunar) mobility and sampling capability is required to support proposed future National Aeronautics and Space Administration (NASA) solar system exploration missions. The NASA Office of Aeronautics and Space Technology (OAST) is addressing some of these technology needs in its base research and development program, the Civil Space Technology Initiative (CSTI) and a new technology initiative entitled Pathfinder. The Pathfinder Planetary Rover (PPR) and Sample Acquisition, Analysis and Preservation (SAAP) programs will develop and validate the technologies needed to enable both robotic and piloted rovers on various planetary surfaces. The technology requirements for a planetary roving vehicle and the development plans of the PPR and SAAP programs are discussed

Dual Quaternion Sample Reduction for SE(2) Estimation

We present a novel sample reduction scheme for random variables belonging to the SE(2) group by means of Dirac mixture approximation. For this, dual quaternions are employed to represent uncertain planar transformations. The Cramér–von Mises distance is modified as a smooth metric to measure the statistical distance between Dirac mixtures on the manifold of planar dual quaternions. Samples of reduced size are then obtained by minimizing the probability divergence via Riemannian optimization while interpreting the correlation between rotation and translation. We further deploy the proposed scheme for nonparametric modeling of estimates for nonlinear SE(2) estimation. Simulations show superior tracking performance of the sample reduction-based filter compared with Monte Carlo-based as well as parametric model-based planar dual quaternion filters

Robotics technology discipline

Viewgraphs on robotics technology discipline for Space Station Freedom are presented. Topics covered include: mechanisms; sensors; systems engineering processes for integrated robotics; man/machine cooperative control; 3D-real-time machine perception; multiple arm redundancy control; manipulator control from a movable base; multi-agent reasoning; and surfacing evolution technologies

Progress toward multi‐robot reconnaissance and the MAGIC 2010 competition

Tasks like search‐and‐rescue and urban reconnaissance benefit from large numbers of robots working together, but high levels of autonomy are needed to reduce operator requirements to practical levels. Reducing the reliance of such systems on human operators presents a number of technical challenges, including automatic task allocation, global state and map estimation, robot perception, path planning, communications, and human‐robot interfaces. This paper describes our 14‐robot team, which won the MAGIC 2010 competition. It was designed to perform urban reconnaissance missions. In the paper, we describe a variety of autonomous systems that require minimal human effort to control a large number of autonomously exploring robots. Maintaining a consistent global map, which is essential for autonomous planning and for giving humans situational awareness, required the development of fast loop‐closing, map optimization, and communications algorithms. Key to our approach was a decoupled centralized planning architecture that allowed individual robots to execute tasks myopically, but whose behavior was coordinated centrally. We will describe technical contributions throughout our system that played a significant role in its performance. We will also present results from our system both from the competition and from subsequent quantitative evaluations, pointing out areas in which the system performed well and where interesting research problems remain. © 2012 Wiley Periodicals, Inc.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/93532/1/21426_ftp.pd

NASA information sciences and human factors program

The FY-90 descriptions of technical accomplishments are contained in seven sections: Automation and Robotics, Communications, Computer Sciences, Controls and Guidance, Data Systems, Human Factors, and Sensor Technology

Search-Based Motion Planning for Performance Autonomous Driving

Driving on the limits of vehicle dynamics requires predictive planning of future vehicle states. In this work, a search-based motion planning is used to generate suitable reference trajectories of dynamic vehicle states with the goal to achieve the minimum lap time on slippery roads. The search-based approach enables to explicitly consider a nonlinear vehicle dynamics model as well as constraints on states and inputs so that even challenging scenarios can be achieved in a safe and optimal way. The algorithm performance is evaluated in simulated driving on a track with segments of different curvatures.Comment: Accepted to IAVSD 201

ABORDAJE DE LAS DEFICIENCIAS NUTRICIONALES PRE Y POST CIRUGÍA BARIÁTRICA: UNA REVISION NARRATIVA

Obesity is a metabolic, chronic and multifactorial disease that requires stepped and multidisciplinary treatment. Bariatric Surgery is treatment option for patients with severe obesity with or without the presence of associated metabolic diseases. The rate of acute post-surgery complications is low due to minimally invasive techniques incorporation and the interdisciplinary approach. The most prevalent chronic complications are micronutrient deficiencies, and their appearance frecuency can be reduced with long- term clinical, biochemical and nutritional follow-up. Consensus Documents of various Scientific Societies consider postoperative follow-up essential by evaluating the results, comorbidities evolution, weight loss and biochemical-nutritional evaluation. Hidden malnutrition exists in a high number of candidate bariatric surgery patients, that is, micronutrient deficiencies both before and after surgery. The most common deficiencies in patients with severe obesity before and after bariatric surgery are related to the following nutrients: proteins, iron, calcium, vitamins B1, B12, A, D and folic acid, so their periodic determination is recommended. In addition, albumin determination is recommended in order to complete the preoperative evaluation. Other advisable determinations are microminerals (zinc, copper) vitamins B6 and B2. Biochemical evaluation is important to perform before and after surgery. This narrative review will cover the clinical and biochemical deficiencies identification in protein, zinc, iron, copper and the most affected vitamins, before and after bariatric surgery, as well as the current nutritional recommendations for their prevention and/or treatment.La obesidad es una enfermedad metabólica, crónica y multifactorial que requiere tratamiento escalonado y multidisciplinario. La Cirugía Bariátrica constituye una opción de tratamiento para pacientes con obesidad severa, con o sin presencia de enfermedades metabólicas asociadas. La tasa de complicaciones agudas post cirugía es baja debido a la incorporación de técnicas mini-invasivas y al abordaje interdisciplinario. Las complicaciones crónicas prevalentes son las deficiencias de micronutrientes, pudiendo reducir su frecuencia de aparición con seguimiento clínico, bioquímico y nutricional a largo plazo. Los Documentos de Consenso de diversas Sociedades Científicas consideran esencial el seguimiento postoperatorio mediante la evaluación de los resultados, evolución de las comorbilidades, pérdida de peso y evaluación bioquímico-nutricional. Un elevado número de pacientes candidatos a cirugía bariátrica presentan malnutrición oculta con deficiencias de macro y micronutrientes, tanto previamente como a posteriori de la cirugía. Las deficiencias más comunes en pacientes con obesidad severa pre y post cirugía bariátrica se relacionan con los siguientes nutrientes: proteínas, hierro, calcio, vitaminas B1, B12, A, D y ácido fólico por lo que se recomienda su determinación periódica. Además, se recomienda determinar la albúmina para completar la evaluación preoperatoria. Otras determinaciones aconsejables son los microminerales zinc, cobre, vitaminas B6 y B2. La evaluación bioquímica es importante realizarla antes y después del acto quirúrgico. La presente revisión narrativa abarcará la identificación clínica y bioquímica de las deficiencias de proteínas, zinc, hierro, cobre y de las vitaminas mas afectadas, antes y después de la cirugía bariátrica, así como de las actuales recomendaciones nutricionales para su prevención y/o tratamiento

Autonomous Navigation for Autonomous Underwater Vehicles Based on Information Filters and Active Sensing

This paper addresses an autonomous navigation method for the autonomous underwater vehicle (AUV) C-Ranger applying information-filter-based simultaneous localization and mapping (SLAM), and its sea trial experiments in Tuandao Bay (Shangdong Province, P.R. China). Weak links in the information matrix in an extended information filter (EIF) can be pruned to achieve an efficient approach-sparse EIF algorithm (SEIF-SLAM). All the basic update formulae can be implemented in constant time irrespective of the size of the map; hence the computational complexity is significantly reduced. The mechanical scanning imaging sonar is chosen as the active sensing device for the underwater vehicle, and a compensation method based on feedback of the AUV pose is presented to overcome distortion of the acoustic images due to the vehicle motion. In order to verify the feasibility of the navigation methods proposed for the C-Ranger, a sea trial was conducted in Tuandao Bay. Experimental results and analysis show that the proposed navigation approach based on SEIF-SLAM improves the accuracy of the navigation compared with conventional method; moreover the algorithm has a low computational cost when compared with EKF-SLAM