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Abstract: A diagnostic platform for the early functional assessment of post-stroke patients was designed in order to perform isometric measurements during activities of daily living (ADL) tasks. The outcome of these measurements can contribute to verify the integrity of a post-stroke existing or altered “internal model” for a particular functional task. A complete and reliable software application for the diagnostic platform was designed, developed and tested in three European hospitals. The software application was divided into two main modules: a graphical user interface (GUI) and the data pre-processing techniques for the interpretation of recorded biomedical and clinical data. This paper presents the software application associated to the platform, aimed at analysing and interpreting the huge amount of data recorded and collected during the experimental trials. Its main objective is related to validating the onset detection and data reduction. The software application presented in this paper has been working and validated with success in three different clinical centres in Europe and it can be effectively used both as assessment tool in rehabilitation and as research tool in neuroscience. [Copyright &y& Elsevier]

Abstract: Objective: To show that it is possible to determine segment masses and segment centers of mass by measuring manipulator-hand contact forces and joint angles during upper extremity movement. Background: The method serves as a quick subject specific body segment parameter evaluation technique. Clinically we see this method as an alternative upper extremity body segment parameter evaluation study especially useful in rehabilitation treatment activities. Methods: The experiment is based on coupling the human arm with a robotic manipulator which is then used for imposing a specified sagittal plane trajectory. Joint angles and forces in the contact point serve as input to the identification procedure. For verification purposes the proposed identification procedure was first performed on a mechanical arm. Afterwards a low velocity trajectory was imposed into all joints of the human upper extremity, with very small angular deviations. Within this small angular region the arm was assumed to be represented as a linear system. Findings: The outcome of the identification procedure is an estimate of masses and center of mass coordinates for the lower arm and palm segments, their products for the upper arm and the passive moments around the measured angle of all joints in the sagittal plane. The results obtained for three particular human arms are eventually compared to the average population based literature. Conclusion: From the clinical point of view the study can become useful for biomechanical evaluation and for evaluating biomechanical properties of lower extremities or other body segments. This method may also provide a foundation to measuring body segment moments of inertia and joint viscoelastic parameters. [Copyright &y& Elsevier]

Abstract: This paper presents the development and evaluation of the measurement setup for a real-time biomechanical analysis of rowing on an ergometer. The setup consists of a measurement system and a system for data processing. The measurement system consists of a Concept2 rowing ergometer instrumented by force sensors, incremental encoders and an optical system for measuring the kinematics. The measurement data is used as an input to a dynamic model which calculates the rower’s body joint loadings. Real-time data processing and analysis provide real-time feedback on rowing performance and technique to the user. For the evaluation of assessment methodology, five top-level rowers and five non-experts newly introduced to rowing participated in an evaluation experiment. The noticeable distinctions between the measured parameters in the experts and non-experts were measured. The results show that this measurement setup can be successfully used for detailed characterization of rowing technique. [Copyright &y& Elsevier]

Abstract: A system for accurate real-time measurement of deflections was developed. A stable laser source is, by means of a single-mode fiber, coupled to an optical head located at one end of deformed structure. A detector circuit with a quadrant detector and processing electronics, located at the other end of the structure, communicates the resolved 2D position of the incident beam over a common digital bus. Experiments using interferometers were conducted in a climate-controlled chamber to evaluate system performance and verify the accuracy. A resolution of 0.1  m is attainable in dynamic measurements. The system was calibrated and tested to yield measurement accuracy of 0.8  m for 2 probability over the measurement range of 300  m. Drift of the system in the experimental setup was determined to be less than 2  m for measurement in both degrees of freedom within the 10 h period under constant environmental conditions. [Copyright &y& Elsevier]

Abstract: This paper presents algorithms for detection of gait initiation and termination using wearable inertial measurement units and pressure-sensitive insoles. Body joint angles, joint angular velocities, ground reaction force and center of plantar pressure of each foot are obtained from these sensors and input into supervised machine learning algorithms. The proposed initiation detection method recognizes two events: gait onset (an anticipatory movement preceding foot lifting) and toe-off. The termination detection algorithm segments gait into steps, measures the signals over a buffer at the beginning of each step, and determines whether this measurement belongs to the final step. The approach is validated with 10 subjects at two gait speeds, using within-subject and subject-independent cross-validation. Results show that gait initiation can be detected timely and accurately, with few errors in the case of within-subject cross-validation and overall good performance in subject-independent cross-validation. Gait termination can be predicted in over 80% of trials well before the subject comes to a complete stop. Results also show that the two sensor types are equivalent in predicting gait initiation while inertial measurement units are generally superior in predicting gait termination. Potential use of the algorithms is foreseen primarily with assistive devices such as prostheses and exoskeletons. [Copyright &y& Elsevier]

Abstract: The article describes the development and testing of a measurement and control system in industrial environment. This system enables fast and accurate membrane expansion measurements. The membrane is part of the sensor system called diastat, which is filled with a special oil. The diastat is part of mechanical capillary thermostat. To demonstrate the right selection of the measurement equipment and data processing methods, several tests and analysis were performed: the dynamic response of the diastat membrane during filling, measuring accuracy, nonlinearity and temperature stability of the measurement system with integrated distance sensor and the most important verification measurements with reference control procedures in manufacturing process. It was demonstrated that a number of novel approaches need to be introduced enabling installation of the measurement and control system in the production of the thermostat diastats. [Copyright &y& Elsevier]

Abstract: An interactive wheeled vehicle simulator is described, consisting of a software application for simulating vehicle dynamics and presenting the results in virtual 3D environment, and a haptic interface. The latter consists of a hydraulically actuated active seat and an electrically activated active steering wheel. The system makes it possible to simulate wheeled vehicles of various configurations on arbitrary terrains. The design of the system is presented and the specific considerations are discussed. The system was experimentally verified by measurements on a real off-road vehicle. The kinematic values measured on the real vehicle and those, measured on the haptic interface were compared. The results are discussed and are generally found to correspond well, making the system usable for studying vehicle performance and training its operators. [Copyright &y& Elsevier]