The Experts below are selected from a list of 34446 Experts worldwide ranked by ideXlab platform

Atsuo Takanishi - One of the best experts on this subject based on the ideXlab platform.

  • walking assessment in the phase space by using ultra miniaturized Inertial Measurement units
    International Conference on Mechatronics and Automation, 2013
    Co-Authors: Salvatore Sessa, Z. Lin, Luca Bartolomeo, Massimiliano Zecca, K Saito, Sarah Cosentino, H Ishii, T Ikai, Atsuo Takanishi
    Abstract:

    Physical therapy helps patients to restore the use of the musculoskeletal and the nervous systems through the use of specifics techniques and exercises. The introduction of Measurement systems for patient assessment may allow detection of initial stage of diseases, an objective severity assessment, and efficient delivery of drugs and therapies. In rehabilitation centers, sometimes there are specific devices and methodologies available for the locomotion assessment. However, the Measurements are usually carried out in a short time slot and this could lead to an overestimation of the walking abilities. The authors propose a system, named WB-4R, which can provide a fast and objective walking assessment using a set of Inertial Measurement Units (IMUs). The WB-4R can be used for the gait analysis in rehabilitation centers or at home because it is compact and relatively maintenance-free. In this paper, it will be shown that our system is able to reconstruct the joint angles of lower limbs and build a foot phase space diagram during straight line walking. Furthermore, we compared the results with an optical system used in the clinical practice.

  • A Methodology for the Performance Evaluation of Inertial Measurement Units
    Journal of Intelligent and Robotic Systems, 2012
    Co-Authors: Salvatore Sessa, Z. Lin, Luca Bartolomeo, Massimiliano Zecca, H Ishii, Atsuo Takanishi
    Abstract:

    This paper presents a methodology for a reliable comparison among Inertial Measurement Units or attitude estimation devices in a Vicon environment. The misalignment among the reference systems and the lack of synchronization among the devices are the main problems for the correct performance evaluation using Vicon as reference Measurement system. We propose a genetic algorithm coupled with Dynamic Time Warping (DTW) to solve these issues. To validate the efficacy of the methodology, a performance comparison is implemented between the WB-3 ultra-miniaturized Inertial Measurement Unit (IMU), developed by our group, with the commercial IMU InertiaCube3? by InterSense.

  • Development of the wireless ultra-miniaturized Inertial Measurement unit WB-4: Preliminary performance evaluation
    Proceedings of the Annual International Conference of the IEEE Engineering in Medicine and Biology Society EMBS, 2011
    Co-Authors: Z. Lin, Luca Bartolomeo, Massimiliano Zecca, H Ishii, Salvatore Sessa, Atsuo Takanishi
    Abstract:

    This paper presents the preliminary performance evaluation of our new wireless ultra-miniaturized Inertial Measurement unit (IMU) WB-4 by compared with the Vicon motion capture system. The WB-4 IMU primarily contains a mother board for motion sensing, a Bluetooth module for wireless data transmission with PC, and a Li-Polymer battery for power supply. The mother board is provided with a microcontroller and 9-axis Inertial sensors (miniaturized MEMS accelerometer, gyroscope and magnetometer) to measure orientation. A quaternion-based extended Kalman filter (EKF) integrated with an R-Adaptive algorithm for automatic estimation of the Measurement covariance matrix is implemented for the sensor fusion to retrieve the attitude. The experimental results showed that the wireless ultra-miniaturized WB-4 IMU could provide high accuracy performance at the angles of roll and pitch. The yaw angle which has reasonable performance needs to be further evaluated.

Xianghong Cheng - One of the best experts on this subject based on the ideXlab platform.

  • optimized multi position calibration method with nonlinear scale factor for Inertial Measurement units
    Sensors, 2019
    Co-Authors: Zihui Wang, Xianghong Cheng
    Abstract:

    Navigation grade Inertial Measurement units (IMUs) should be calibrated after Inertial Navigation Systems (INSs) are assembled and be re-calibrated after certain periods of time. The multi-position calibration methods with advantage of not requiring high-precision equipment are widely discussed. However, the existing multi-position calibration methods for IMU are based on the model of linear scale factors. To improve the precision of INS, the nonlinear scale factors should be calibrated accurately. This paper proposes an optimized multi-position calibration method with nonlinear scale factor for IMU, and the optimal calibration motion of IMU has been designed based on the analysis of sensitivity of the cost function to the calibration parameters. Besides, in order to improve the accuracy and robustness of the optimization, an estimation method on initial values is presented to solve the problem of setting initial values for iterative methods. Simulations and experiments show that the proposed method outperforms the calibration method without nonlinear scale factors. The navigation accuracy of INS can be improved by up to 17% in lab conditions and 12% in the moving vehicle experiment, respectively.

Salvatore Sessa - One of the best experts on this subject based on the ideXlab platform.

  • application of wireless Inertial Measurement units and emg sensors for studying deglutition preliminary results
    International Conference of the IEEE Engineering in Medicine and Biology Society, 2014
    Co-Authors: U Imtiaz, W Kong, Luca Artolomeo, Massimiliano Zecca, H Ishii, Salvatore Sessa, Kensuke Yamamura, Yoshiaki Yamada
    Abstract:

    Different types of sensors are being used to study deglutition and mastication. These often suffer from problems related to portability, cost, reliability, comfort etc. that make it difficult to use for long term studies. An Inertial Measurement based sensor seems a good fit in this application; however its use has not been explored much for the specific application of deglutition research. In this paper, we present a system comprised of an IMU and EMG sensor that are integrated together as a single system. With a preliminary experiment, we determine that the system can be used for measuring the head-neck posture during swallowing in addition to other parameters during the swallowing phase. The EMG sensor may not always be a reliable source of physiological data especially for small clustered muscles like the ones responsible for swallowing. In this case, we explore the possibility of using gyroscopic data for the recognition of deglutition events.

  • walking assessment in the phase space by using ultra miniaturized Inertial Measurement units
    International Conference on Mechatronics and Automation, 2013
    Co-Authors: Salvatore Sessa, Z. Lin, Luca Bartolomeo, Massimiliano Zecca, K Saito, Sarah Cosentino, H Ishii, T Ikai, Atsuo Takanishi
    Abstract:

    Physical therapy helps patients to restore the use of the musculoskeletal and the nervous systems through the use of specifics techniques and exercises. The introduction of Measurement systems for patient assessment may allow detection of initial stage of diseases, an objective severity assessment, and efficient delivery of drugs and therapies. In rehabilitation centers, sometimes there are specific devices and methodologies available for the locomotion assessment. However, the Measurements are usually carried out in a short time slot and this could lead to an overestimation of the walking abilities. The authors propose a system, named WB-4R, which can provide a fast and objective walking assessment using a set of Inertial Measurement Units (IMUs). The WB-4R can be used for the gait analysis in rehabilitation centers or at home because it is compact and relatively maintenance-free. In this paper, it will be shown that our system is able to reconstruct the joint angles of lower limbs and build a foot phase space diagram during straight line walking. Furthermore, we compared the results with an optical system used in the clinical practice.

  • A Methodology for the Performance Evaluation of Inertial Measurement Units
    Journal of Intelligent and Robotic Systems, 2012
    Co-Authors: Salvatore Sessa, Z. Lin, Luca Bartolomeo, Massimiliano Zecca, H Ishii, Atsuo Takanishi
    Abstract:

    This paper presents a methodology for a reliable comparison among Inertial Measurement Units or attitude estimation devices in a Vicon environment. The misalignment among the reference systems and the lack of synchronization among the devices are the main problems for the correct performance evaluation using Vicon as reference Measurement system. We propose a genetic algorithm coupled with Dynamic Time Warping (DTW) to solve these issues. To validate the efficacy of the methodology, a performance comparison is implemented between the WB-3 ultra-miniaturized Inertial Measurement Unit (IMU), developed by our group, with the commercial IMU InertiaCube3? by InterSense.

  • Development of the wireless ultra-miniaturized Inertial Measurement unit WB-4: Preliminary performance evaluation
    Proceedings of the Annual International Conference of the IEEE Engineering in Medicine and Biology Society EMBS, 2011
    Co-Authors: Z. Lin, Luca Bartolomeo, Massimiliano Zecca, H Ishii, Salvatore Sessa, Atsuo Takanishi
    Abstract:

    This paper presents the preliminary performance evaluation of our new wireless ultra-miniaturized Inertial Measurement unit (IMU) WB-4 by compared with the Vicon motion capture system. The WB-4 IMU primarily contains a mother board for motion sensing, a Bluetooth module for wireless data transmission with PC, and a Li-Polymer battery for power supply. The mother board is provided with a microcontroller and 9-axis Inertial sensors (miniaturized MEMS accelerometer, gyroscope and magnetometer) to measure orientation. A quaternion-based extended Kalman filter (EKF) integrated with an R-Adaptive algorithm for automatic estimation of the Measurement covariance matrix is implemented for the sensor fusion to retrieve the attitude. The experimental results showed that the wireless ultra-miniaturized WB-4 IMU could provide high accuracy performance at the angles of roll and pitch. The yaw angle which has reasonable performance needs to be further evaluated.

Marko Munih - One of the best experts on this subject based on the ideXlab platform.

  • Toward Real-Time Automated Detection of Turns during Gait Using Wearable Inertial Measurement Units
    Sensors, 2014
    Co-Authors: Domen Novak, Maja Gorsic, Janez Podobnik, Marko Munih
    Abstract:

    Previous studies have presented algorithms for detection of turns during gait using wearable sensors, but those algorithms were not built for real-time use. This paper therefore investigates the optimal approach for real-time detection of planned turns during gait using wearable Inertial Measurement units. Several different sensor positions (head, back and legs) and three different detection criteria (orientation, angular velocity and both) are compared with regard to their ability to correctly detect turn onset. Furthermore, the different sensor positions are compared with regard to their ability to predict the turn direction and amplitude. The evaluation was performed on ten healthy subjects who performed left/right turns at three amplitudes (22, 45 and 90 degrees). Results showed that turn onset can be most accurately detected with sensors on the back and using a combination of orientation and angular velocity. The same setup also gives the best prediction of turn direction and amplitude. Preliminary Measurements with a single amputee were also performed and highlighted important differences such as slower turning that need to be taken into account.

  • development and validation of a wearable Inertial Measurement system for use with lower limb exoskeletons
    IEEE-RAS International Conference on Humanoid Robots, 2011
    Co-Authors: Tadej Beravs, Domen Novak, Janez Podobnik, Peter Rebersek, Marko Munih
    Abstract:

    This paper presents a system of Inertial Measurement units, each consisting of an accelerometer, gyroscope and magnetometer. They are characterized by a small size, wireless transmission, and open architecture, with the purpose of either integration into lower limb exoskeletons or general human movement analysis. Kalman filtering and the factored quaternion algorithm are used to track the orientation of each unit, and angles of the human joints are calculated from multiple units. After calibration, the system was tested with a wooden leg mockup and an actual human. The Optotrak optical Measurement system was used as a reference. Differences between the Inertial Measurement system and the Optotrak were less than 2 degrees for the wooden leg and less than 5 degrees for the human leg, suggesting that the system represents a promising possibility for wearable movement tracking and analysis.

Z. Lin - One of the best experts on this subject based on the ideXlab platform.

  • walking assessment in the phase space by using ultra miniaturized Inertial Measurement units
    International Conference on Mechatronics and Automation, 2013
    Co-Authors: Salvatore Sessa, Z. Lin, Luca Bartolomeo, Massimiliano Zecca, K Saito, Sarah Cosentino, H Ishii, T Ikai, Atsuo Takanishi
    Abstract:

    Physical therapy helps patients to restore the use of the musculoskeletal and the nervous systems through the use of specifics techniques and exercises. The introduction of Measurement systems for patient assessment may allow detection of initial stage of diseases, an objective severity assessment, and efficient delivery of drugs and therapies. In rehabilitation centers, sometimes there are specific devices and methodologies available for the locomotion assessment. However, the Measurements are usually carried out in a short time slot and this could lead to an overestimation of the walking abilities. The authors propose a system, named WB-4R, which can provide a fast and objective walking assessment using a set of Inertial Measurement Units (IMUs). The WB-4R can be used for the gait analysis in rehabilitation centers or at home because it is compact and relatively maintenance-free. In this paper, it will be shown that our system is able to reconstruct the joint angles of lower limbs and build a foot phase space diagram during straight line walking. Furthermore, we compared the results with an optical system used in the clinical practice.

  • A Methodology for the Performance Evaluation of Inertial Measurement Units
    Journal of Intelligent and Robotic Systems, 2012
    Co-Authors: Salvatore Sessa, Z. Lin, Luca Bartolomeo, Massimiliano Zecca, H Ishii, Atsuo Takanishi
    Abstract:

    This paper presents a methodology for a reliable comparison among Inertial Measurement Units or attitude estimation devices in a Vicon environment. The misalignment among the reference systems and the lack of synchronization among the devices are the main problems for the correct performance evaluation using Vicon as reference Measurement system. We propose a genetic algorithm coupled with Dynamic Time Warping (DTW) to solve these issues. To validate the efficacy of the methodology, a performance comparison is implemented between the WB-3 ultra-miniaturized Inertial Measurement Unit (IMU), developed by our group, with the commercial IMU InertiaCube3? by InterSense.

  • Development of the wireless ultra-miniaturized Inertial Measurement unit WB-4: Preliminary performance evaluation
    Proceedings of the Annual International Conference of the IEEE Engineering in Medicine and Biology Society EMBS, 2011
    Co-Authors: Z. Lin, Luca Bartolomeo, Massimiliano Zecca, H Ishii, Salvatore Sessa, Atsuo Takanishi
    Abstract:

    This paper presents the preliminary performance evaluation of our new wireless ultra-miniaturized Inertial Measurement unit (IMU) WB-4 by compared with the Vicon motion capture system. The WB-4 IMU primarily contains a mother board for motion sensing, a Bluetooth module for wireless data transmission with PC, and a Li-Polymer battery for power supply. The mother board is provided with a microcontroller and 9-axis Inertial sensors (miniaturized MEMS accelerometer, gyroscope and magnetometer) to measure orientation. A quaternion-based extended Kalman filter (EKF) integrated with an R-Adaptive algorithm for automatic estimation of the Measurement covariance matrix is implemented for the sensor fusion to retrieve the attitude. The experimental results showed that the wireless ultra-miniaturized WB-4 IMU could provide high accuracy performance at the angles of roll and pitch. The yaw angle which has reasonable performance needs to be further evaluated.