You can find here several publications where our products have been used as research tools.
Validation of distal limb mounted inertial-measurement-unit sensors for stride detection in Warmblood horses at walk and trot
Bragança F.M., Bosch S., Voskamp J., Marin-Perianu M., Van der Zwaag B.J., Vernooij J. C. M., Van Weeren P.R. and Back W. (2016), Equine Veterinary Journal ISSN 2042-3306
Inertial-measurement-unit (IMU)-sensor-based techniques are becoming more popular in horses as a tool for objective locomotor assessment.
Objectives: To describe, evaluate and validate a method of stride detection and quantification at walk and trot using distal limb mounted IMU-sensors.
Study design: Prospective validation study comparing IMU-sensors and motion capture with force plate data.
Methods: Seven Warmblood horses equipped with metacarpal/metatarsal IMU-sensors and reflective markers for motion capture were hand walked and trotted over a force plate. Using four custom-built algorithms hoof-on/off timing over the force plate were calculated for each trial from the IMU data. Accuracy of the computed parameters was calculated as the mean difference in milliseconds between the IMU or motion capture generated data and the data from the force plate, precision as the s.d. of these differences and percentage of error with accuracy of the calculated parameter as a percentage of the force plate stance duration.
Results: Accuracy, precision and percentage of error of the best performing IMU algorithm for stance duration at walk were 28.5 ms, 31.6 ms and 3.7% for the forelimbs and -5.5 ms, 20.1 ms and -0.8% for the hindlimbs respectively. At trot the best performing algorithm achieved accuracy, precision and percentage of error of -27.6 ms/8.8 ms/-8.4% for the forelimbs and 6.3 ms/33.5 ms/9.1% for the hind limbs.
Main limitations: The described algorithms have not been assessed on different surfaces.
Conclusions: IMU technology can be used to determine temporal kinematic stride variables at walk and trot justifying its use in gait and performance analysis. However, precision of the method may not be sufficient to detect all possible lameness-related changes. These data seem promising enough to warrant further research to evaluate whether this approach will be useful for appraising the majority of clinically relevant gait changes encountered in practice.
Bosch, S. and Shoaib, M. and Geerlings, Stephen and Buit, Lennart and Meratnia, N. and Havinga, P.J.M. (2015) Analysis of Indoor Rowing Motion using Wearable Inertial Sensors. In: Proceedings of the 10th EAI International Conference on Body Area Networks, BODYNETS 2015, 28-30 Sep 2015, Sydney, Australia. ACM.
In this exploratory work the motion of rowers is analyzed while rowing on a rowing machine. This is performed using inertial sensors that measure the orientation at several positions on the body. Using these measurements, this work provides a preliminary analysis of the differences between experienced and novice rowers, or between a good and a bad technique. The analysis shows that the measured postural angles show no clear trend that would set apart experienced and novice rowers or a bad and a good technique. However, there are clear differences in absolute postural angle’s consistency and timing consistency of strokes between novice and experienced rowers. We also applied a machine learning technique to the data to find the similarities between different rowers and an experienced reference rower. The results can be used to compare the quality of the rowing technique with respect to a reference. In this paper, we present our initial results as well as the challenges that need to be further explored.
Acceptance and usability of technology-supported interventions for motivating patients with COPD to be physically active
Tabak, Monique and Hermens, Hermie and Marin-Perianu, Raluca and Burkow, Tatjana and Ciobanu, Ileana and Berteanu, Mihai (2013) Acceptance and usability of technology-supported interventions for motivating patients with COPD to be physically active. IADIS international journal on www/internet, 11 (3). pp. 103-115. ISSN 1645-7641
In chronic care, technology can play an important role to increase the quality and efficiency of healthcare. But to be successful, healthcare technology needs to be acceptable, usable, and easily integrated into daily life. As a consequence, end-users need to be actively involved in the design process. In the European IS-ACTIVE project, we developed technology-supported interventions that promote physical activity in patients with COPD, by using an ambulant activity coach and an interactive game. In this paper, we elaborate on the design, involving the end-users, to develop interventions that are highly usable and well accepted.
Mark Olieman, Raluca Marin-Perianu, Mihai Marin-Perianu (2012) Measurement of dynamic comfort in cycling using wireless acceleration sensors
Comfort in cycling is related to the level of vibration of the bicycle: more vibration results in less comfort for the rider. In this study, the level of vibration is measured in real time using wireless inertial acceleration sensors mounted at four places on the bike: front wheel axel, rear wheel axel, stem and seatpost. In this way, we measure both the input and output of the frame and fork, and consequently establish the transfer function of the frame and front fork. Besides the transfer of vibrations through the frame, we also investigate the input to the frame and fork. Moreover, we determine the effect of the road surface, speed, wheels and tire pressure on the vibrations induced to the frame and fork. Our analysis shows that road surface, speed and the tire pressure have a significant influence on the induced vibrations. On the contrary different wheelsets have no significant influence. Additionally, the vibrations propagate through the frame within a duration of 5 ms.
Marin-Perianu, R.S. and Marin-Perianu, M. and Havinga, P.J.M. and Taylor, S. and Begg, R. and Palaniswami, M. and Rouffet, D. (2013) A Performance Analysis of a Wireless Body-Area Network Monitoring System for Professional Cycling. Personal and Ubiquitous Computing, 17 (1). 197-209. ISSN 1617-4909
It is essential for any highly trained cyclist to optimize his pedalling movement in order to maximize the performance and minimize the risk of injuries. Current techniques rely on bicycle fitting and off-line laboratory measurements. These techniques do not allow the assessment of the kinematics of the cyclist during training and competition, when fatigue may alter the ability of the cyclist to apply forces to the pedals and thus induce maladaptive joint loading. We propose a radically different approach that focuses on determining the actual status of the cyclist’s lower limb segments in real-time and real-life conditions. Our solution is based on body area wireless motion sensor nodes that can collaboratively process the sensory information and provide the cyclists with immediate feedback about their pedalling movement. In this paper, we present a thorough study of the accuracy of our system with respect to the gold standard motion capture system. We measure the knee and ankle angles, which influence the performance as well as the risk of overuse injuries during cycling. The results obtained from a series of experiments with nine subjects show that the motion sensors are within 2.2° to 6.4° from the reference given by the motion capture system, with a correlation coefficient above 0.9. The wireless characteristics of our system, the energy expenditure, possible improvements and usability aspects are further analysed and discussed.
Bosch, S. and Marin-Perianu, R.S. and Havinga, P.J.M. and Horst, A.P. and Marin-Perianu, M. and Vasilescu, A. (2012) A study on automatic recognition of object use exploiting motion correlation of wireless sensors. Personal and Ubiquitous Computing, 16 (7). 875-895. ISSN 1617-4909
An essential component in the ubiquitous computing vision is the ability of detecting with which objects the user is interacting during his or her activities. We explore in this paper a solution to this problem based on wireless motion and orientation sensors (accelerometer and compass) worn by the user and attached to objects. We evaluate the performance in realistic conditions, characterized by limited hardware resources, measurement noise due to motion artifacts and unreliable wireless communication. We describe the complete solution, from the theoretical design, going through simulation and tuning, to the full implementation and testing on wireless sensor nodes. The implementation on sensor nodes is lightweight, with low communication bandwidth and processing needs. Compared to existing work, our approach achieves better performance (higher detection accuracy and faster response times), while being much more computationally efficient. The potential of the concept is further illustrated by means of an interactive multi-user game. We also provide a thorough discussion of the advantages, limitations and trade-offs of the proposed solution.