{"title":"Indirect Force Measurement for Hydraulic Walking Robot","authors":"S. Nabulsi, J. Sarria, M. Armada","doi":"10.1109/WISP.2007.4447620","DOIUrl":"https://doi.org/10.1109/WISP.2007.4447620","url":null,"abstract":"Force sensing is an important issue for the control of legged robots. In this paper an indirect force measurement for hydraulic walking robots is presented. The test case is ROBOCLIMBER, a bulky, quadruped climbing and walking machine whose weighty legs enable it to carry out heavy-duty drilling operations. The paper shows how the placement of pressure transducers at both ends of the double effect hydraulic jacks allows measuring indirectly the contact forces between the feet and the ground. Several experiments are carried out to calibrate all sensors within their operational range of interest. Because of dynamic properties of hydraulic cylinders friction modelling is an important task to be carried out in order to determine at all times the true forces of the feet against the soil. After calibration and friction modelling, sensors are subjected to experimental performance evaluation.","PeriodicalId":164902,"journal":{"name":"2007 IEEE International Symposium on Intelligent Signal Processing","volume":"33 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132751256","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
P. Núñez, R. Vázquez, J. del Toro, A. Bandera, F. Sandoval
{"title":"A Curvature based Method to Extract Natural Landmarks for Mobile Robot Navigation","authors":"P. Núñez, R. Vázquez, J. del Toro, A. Bandera, F. Sandoval","doi":"10.1109/WISP.2007.4447573","DOIUrl":"https://doi.org/10.1109/WISP.2007.4447573","url":null,"abstract":"Landmark extraction is an essential task for robot navigation which not only requires an effective measure, but also the characterisation of landmarks to reduce the subsequent data association ambiguity. This paper describes a new method to detect natural landmarks from the adaptively estimated curvature function associated to 2D laser scans. This set of landmarks is composed of items associated to real and virtual features of the environment (corners, center of tree-like objects, line segments and edges). A novelty of the proposed system is that, for each landmark, characterisation provides not only the parameter vector, but also complete statistical information. Experimental results show the effectiveness of this method to deal with structured environments.","PeriodicalId":164902,"journal":{"name":"2007 IEEE International Symposium on Intelligent Signal Processing","volume":"22 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134043953","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"An Investigation into Temporal Gamma Luminance for Digital Fringe Fourier Transform Profilometers","authors":"M. Baker, J. Chicharo, J. Xi","doi":"10.1109/WISP.2007.4447501","DOIUrl":"https://doi.org/10.1109/WISP.2007.4447501","url":null,"abstract":"Analysis of the impact of temporal gamma luminance on Fourier transform profllometry (FTP) digital video projection (DVP) based structured light profilometers is undertaken. We investigate the spectral harmonic structure for typical DVP fringe images linking projector gamma and 2nd order fringe harmonics. The validity of the presented study is verified through simulation, and subsequently we conclude that for typical projector 7, the 2nd order harmonic is the single most significant contribution to reconstruction error for the phase measuring technique. The impact of our analysis is further gauged by empirical measurement of the temporal variation of gamma of a DVP device.","PeriodicalId":164902,"journal":{"name":"2007 IEEE International Symposium on Intelligent Signal Processing","volume":"62 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124927963","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Genetic Algorithm Approach to Polyphonic Music Transcription","authors":"G. Reis, N. Fonseca, F. Ferndandez","doi":"10.1109/WISP.2007.4447608","DOIUrl":"https://doi.org/10.1109/WISP.2007.4447608","url":null,"abstract":"Automatic music transcription (extracting musical notes from a polyphonic audio stream) is a very complex task that continues waiting for solutions, due to the harmonic complexity of musical sounds. Traditional approaches try to extract the information directly from the audio stream, but by taking into account that a polyphonic audio stream is no more than a combination of several notes, music transcription can be considered as a search problem where the goal is to find the sequence of the notes that best models our audio signal. By taking advantage of the genetic algorithms to explore a large search space we present a new approach to the music transcription problem. The results obtained show the feasibility of the approach.","PeriodicalId":164902,"journal":{"name":"2007 IEEE International Symposium on Intelligent Signal Processing","volume":"132 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134519953","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Evolutionary Filter for Mobile Robot Global Localization","authors":"L. Moreno, M. L. Muoz, S. Garrido, F. Martín","doi":"10.1109/WISP.2007.4447539","DOIUrl":"https://doi.org/10.1109/WISP.2007.4447539","url":null,"abstract":"Mobile robot global localization aims to determine the robot's pose in a known environment in absence of initial robot's pose information. This article presents an evolutive localization algorithm known as Evolutive Localization filter (ELF). Based on evolutionary computation concepts, the proposed algorithm search stochastically along the state space the best robot's pose estimate. The set of pose solutions (the population) represents the most likely areas according the perception and motion information received. The population evolves by using the observation and motion errors derived from the comparison between observed and predicted data obtained from the probabilistic perception and motion model. The resulting global localization module has been tested in a mobile robot equipped with a laser range finder. Experiments demonstrate the effectiveness, robustness and computational efficiency of the proposed approach.","PeriodicalId":164902,"journal":{"name":"2007 IEEE International Symposium on Intelligent Signal Processing","volume":"3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134147314","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
S. Villazana, C. Seijas, A. Caralli, C. Villanueva, F. Arteaga
{"title":"SVM-based and Classical MRAS for On-line Rotor Resistance Estimation: A Comparative Study","authors":"S. Villazana, C. Seijas, A. Caralli, C. Villanueva, F. Arteaga","doi":"10.1109/WISP.2007.4447592","DOIUrl":"https://doi.org/10.1109/WISP.2007.4447592","url":null,"abstract":"This paper makes a comparison between the performance of a classical model reference adaptive system (MRAS)-based observer to estimate the rotor resistance of the SCIM and the performance of a support vector machines (SVM)-based MRAS observer to estimate that parameter. The most important parameter of the squirrel cage induction motor to be considered in indirect vector control is the rotor resistance; because of this parameter has a strong influence in the performance of the drive. It is well known, if there is a mismatching between rotor resistance of the machine (varying with temperature, saturation, skin effect) and its corresponding one in the controller (fixed), the latter cannot determine the correct position of the synchronous d-q axes and the consequence is the lost of the field orientation. The complete drive system including a time-varying rotor resistance model for the SCIM was simulated. Results showed the performance of the SVM-based estimator was better than performance of the classical MRAS-based estimator for the same operation conditions of the drive system. This work showed the powerful of the SVM used as regressor to estimate an unknown and inaccessible rotor resistance parameter of the SCIM, which demonstrated this new artificial intelligent branch has a promissory future to solve many different problems in engineering field applications.","PeriodicalId":164902,"journal":{"name":"2007 IEEE International Symposium on Intelligent Signal Processing","volume":"56 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132240122","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
R. Vicen-Bueno, A. Martinez-Leira, R. Gil-Pita, M. Rosa-Zurera
{"title":"Acoustic feedback reduction based on Filtered-X LMS and Normalized Filtered-X LMS algorithms in digital hearing aids based on WOLA filterbank","authors":"R. Vicen-Bueno, A. Martinez-Leira, R. Gil-Pita, M. Rosa-Zurera","doi":"10.1109/WISP.2007.4447648","DOIUrl":"https://doi.org/10.1109/WISP.2007.4447648","url":null,"abstract":"The speech signal corrupted by the acoustic feedback in digital hearing aids can be restored by a feedback reduction system using adaptive algorithms such as the least-mean square (LMS) algorithm. The main disadvantage of the LMS algorithm is the instability. In order to avoid this situation, it is used another feedback reduction systems based on two different algorithms: the filtered-X LMS (FXLMS) and the normalized filtered-X LMS (NFXLMS). These algorithms are tested in two digital hearing aid categories: the in-the-ear (ITE) and the in-the-canal (ITC). For both categories, the added stable gain (ASG) value over the limit gain of the digital hearing aids is obtained. The ASG value is achieved as a tradeoff between the segmented signal-to-noise ratio (objective parameter) and the speech quality (subjective parameter). The results show how the digital hearing aid working with a feedback reduction adaptive filter adapted with the NFXLMS algorithm is able to achieve up to 18 dB of increase over the limit gain.","PeriodicalId":164902,"journal":{"name":"2007 IEEE International Symposium on Intelligent Signal Processing","volume":"11 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122320885","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
I. López, R. Sanz, F. Moreno, R. Salvador, J. Alarcón
{"title":"From Cognitive Architectures to Hardware: A Low Cost FPGA-Based Design Experience","authors":"I. López, R. Sanz, F. Moreno, R. Salvador, J. Alarcón","doi":"10.1109/WISP.2007.4447567","DOIUrl":"https://doi.org/10.1109/WISP.2007.4447567","url":null,"abstract":"This paper describes an experiment to implement a high-level, cognitive architecture on limited resources, namely, an altera cyclone/cyclone-II FPGA. It is part of a broader line of research investigating methods of scaling high-level, cognitive or \"intelligent\" architectures into limited resources, for building embedded systems. An artificial vision system for traffic signal detection has been implemented with neural networks, according to the principles of a BB1/AIS blackboard architecture. Different scaling techniques and reductions have been carried out for embedding the system into an FPGA. The paper offers a description of the architectural design and hardware implementation results. A discussion of modularity, possible enhancements and tradeoffs is carried out throughout the paper.","PeriodicalId":164902,"journal":{"name":"2007 IEEE International Symposium on Intelligent Signal Processing","volume":"119 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116611055","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
F. Álvarez, J. Ureña, A. Hernández, A. Jiménez, C. De Marziani, J. M. Villadangos, M.C. Perez
{"title":"Detecting ultrasonic signals in a turbulent atmosphere: performance of different codes","authors":"F. Álvarez, J. Ureña, A. Hernández, A. Jiménez, C. De Marziani, J. M. Villadangos, M.C. Perez","doi":"10.1109/WISP.2007.4447649","DOIUrl":"https://doi.org/10.1109/WISP.2007.4447649","url":null,"abstract":"Signal coding and pulse compression provide ultrasonic systems with the capability to obtain accurate measurements that are nearly independent of the conditions of operation. This property, together with the high robustness to noise also achieved with these techniques, are making possible the development of high reliability systems intended for outdoor operation. However, these systems must face new problems not found indoors, such as the effect of atmospheric turbulence on the shape of the emitted waveforms. This work presents a comparative analysis of the performance of different codes that are used to encode the signals of an ultrasonic sensory system designed to operate under strong turbulence conditions.","PeriodicalId":164902,"journal":{"name":"2007 IEEE International Symposium on Intelligent Signal Processing","volume":"144 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116710621","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Receiver's Multi-Antenna Coupling Cancellation Based on Guided Multi-level Search","authors":"I. Arambasic, F. Quiros, I. Raos","doi":"10.1109/WISP.2007.4447554","DOIUrl":"https://doi.org/10.1109/WISP.2007.4447554","url":null,"abstract":"In order to achieve higher bit rates and gain diversity, recent trends in communication industry include the use of multiple antennas in transmitter and at the receiver. At the same time the terminals are getting smaller incrementing the level of electronic interferences in their interior. In this contribution, the signal distortion known as RF front-end antenna coupling is analyzed. The coupling between antennas is modeled with polynomials limited to third order nonlinear behavior. Nonlinear software decoupling module, located at the output of analog-to-digital (AD) converter, is proposed for coupling cancellation. Inside the module, signal enhancement is achieved with the approximation of inverse nonlinear coupling function with the polynomial of 9th degree. The inverse function is obtained using guided multilevel search approximation method. The proposed coupling cancellation algorithm is analyzed under different system conditions showing excellent coupling cancellation characteristics.","PeriodicalId":164902,"journal":{"name":"2007 IEEE International Symposium on Intelligent Signal Processing","volume":"281 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116570405","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}