No abstract

This paper presents a mapping system that is suitable for small mobile robots. An ad hoc algorithm for mapping based on the Occupancy Grid method has been developed. The algorithm includes some simplifications in order to be used with low-cost hardware resources. The proposed mapping system has been built in order to be completely autonomous and unassisted. The proposal has been tested with a mobile robot that uses infrared sensors to measure distances to obstacles and uses an ultrasonic beacon system for localization, besides wheel encoders. Finally, experimental results are presented.

This is the author’s version of a work that was accepted for publication in Computer Speech and Language. Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms may not be reflected in this document. Changes may have been made to this work since it was submitted for publication. A definitive version was subsequently published in Computer Speech and Language, 28, 3 (2015) DOI: 10.1016/j.csl.2013.10.003One of the aims of Assistive Technologies is to help people with disabilities to communicate with others and to provide means of access to information. As an aid to Deaf people, we present in this work a production-quality rule-based machine system for translating from Spanish to Spanish Sign Language (LSE) glosses, which is a necessary precursor to building a full machine translation system that eventually produces animation output. The system implements a transfer-based architecture from the syntactic functions of dependency analyses. A sketch of LSE is also presented. Several topics regarding translation to sign languages are addressed: the lexical gap, the bootstrapping of a bilingual lexicon, the generation of word order for topic-oriented languages, and the treatment of classifier predicates and classifier names. The system has been evaluated with an open-domain testbed, reporting a 0.30 BLEU (BiLingual Evaluation Understudy) and 42% TER (Translation Error Rate). These results show consistent improvements over a statistical machine translation baseline, and some improvements over the same system preserving the word order in the source sentence. Finally, the linguistic analysis of errors has identified some differences due to a certain degree of structural variation in LSE

No abstract

Low-cost robots are characterized by low computational resources and limited energy supply. Path planning algorithms aim to find the optimal path between two points so the robot consumes as little energy as possible. However, these algorithms were not developed considering computational limitations (i.e., processing and memory capacity). This paper presents the HCTNav path-planning algorithm (HCTLab research group's navigation algorithm). This algorithm was designed to be run in low-cost robots for indoor navigation. The results of the comparison between HCTNav and the Dijkstra's algorithms show that HCTNav's memory peak is nine times lower than Dijkstra's in maps with more than 150,000 cells.

Esta es la versión de autor de la comunicación de congreso publicada en: This is an author produced version of a paper published in:

The use of precalculated duty cycles for power factor correction leads to a significant simplification of the design and a reduction of the final cost. There are previous proposals for handling non-nominal conditions such as input voltage or load variations. However, there are no proposals for handling input frequency variations, which have an important impact in the power factor. This paper measures this impact and includes a simple loop to handle the variations of the input frequency. The results show that the introduction of this loop keeps the power factor values around those obtained in nominal conditions.

Esta es la versión de autor de la comunicación de congreso publicada en: This is an author produced version of a paper published in: AbstractThis work presents a new approach to the synthesis of Spanish Sign Language (LSE). Its main contributions are the use of a centralized relational database for storing sign descriptions, the proposal of a new input notation and a new avatar design, the skeleton structure of which improves the synthesis process.The relational database facilitates a highly detailed phonologic description of the signs that, include parameter synchronization and timing. The centralized database approach has been introduced to allow the representation of each sign to be validated by the LSE national institution, FCNSE.The input notation, designated HLSML, presents multiple levels of abstraction compared with current input notations. Redesigned input notation is used to simplify the description and the manual definition of LSE messages.Synthetic messages obtained using our approach have been evaluated by deaf users; in this evaluation a maximum recognition rate of 98.5% was obtained for isolated signs and a recognition rate of 95% was achieved for signed sentences.