The problem addressed in this report is to verify the possibility of using an optical sensor in the SaxShirt in order to extract the heart rate. There are specifically three questions that we try to address. 1) How is it possible to extract heart rate (BPM) from the optical sensor? 2) Is it possible to use the sensor for extracting BPM during movement? 3) Is the heart rate measured in this way useful for measuring other higher-level parameters such as heart rate coherence and heart rate variability? For this purpose, we have performed tests with the sensor placed on different spots and the data was analyzed to see if heart rate can be extracted from the sensor measurements.
MULTIFILE
To better control the growing process of horticulture plants greenhouse growers need an automated way to efficiently and effectively find where diseases are spreading.The HiPerGreen project has done research in using an autonomous quadcopter for this scouting. In order for the quadcopter to be able to scout autonomously accurate location data is needed. Several different methods of obtaining location data have been investigated in prior research. In this research a relative sensor based on optical flow is looked into as a method of stabilizing an absolute measurement based on trilateration. For the optical flow sensor a novel block matching algorithm was developed. Simulated testing showed that Kalman Filter based sensor fusion of both measurements worked to reduce the standard deviation of the absolute measurement from 30 cm to less than 1 cm, while drift due to dead-reckoning was reduced to a maximum of 11 cm from over 36 cm.
DOCUMENT
In wheelchair sports, the use of Inertial Measurement Units (IMUs) has proven to be one of the most accessible ways for ambulatory measurement of wheelchair kinematics. A three-IMU configuration, with one IMU attached to the wheelchair frame and two IMUs on each wheel axle, has previously shown accurate results and is considered optimal for accuracy. Configurations with fewer sensors reduce costs and could enhance usability, but may be less accurate. The aim of this study was to quantify the decline in accuracy for measuring wheelchair kinematics with a stepwise sensor reduction. Ten differently skilled participants performed a series of wheelchair sport specific tests while their performance was simultaneously measured with IMUs and an optical motion capture system which served as reference. Subsequently, both a one-IMU and a two-IMU configuration were validated and the accuracy of the two approaches was compared for linear and angular wheelchair velocity. Results revealed that the one-IMU approach show a mean absolute error (MAE) of 0.10 m/s for absolute linear velocity and a MAE of 8.1◦/s for wheelchair angular velocity when compared with the reference system. The twoIMU approach showed similar differences for absolute linear wheelchair velocity (MAE 0.10 m/s), and smaller differences for angular velocity (MAE 3.0◦/s). Overall, a lower number of IMUs used in the configuration resulted in a lower accuracy of wheelchair kinematics. Based on the results of this study, choices regarding the number of IMUs can be made depending on the aim, required accuracy and resources available.
DOCUMENT
Various companies in diagnostic testing struggle with the same “valley of death” challenge. In order to further develop their sensing application, they rely on the technological readiness of easy and reproducible read-out systems. Photonic chips can be very sensitive sensors and can be made application-specific when coated with a properly chosen bio-functionalized layer. Here the challenge lies in the optical coupling of the active components (light source and detector) to the (disposable) photonic sensor chip. For the technology to be commercially viable, the price of the disposable photonic sensor chip should be as low as possible. The coupling of light from the source to the photonic sensor chip and back to the detectors requires a positioning accuracy of less than 1 micrometer, which is a tremendous challenge. In this research proposal, we want to investigate which of the six degrees of freedom (three translational and three rotational) are the most crucial when aligning photonic sensor chips with the external active components. Knowing these degrees of freedom and their respective range we can develop and test an automated alignment tool which can realize photonic sensor chip alignment reproducibly and fully autonomously. The consortium with expertise and contributions in the value chain of photonics interfacing, system and mechanical engineering will investigate a two-step solution. This solution comprises a passive pre-alignment step (a mechanical stop determines the position), followed by an active alignment step (an algorithm moves the source to the optimal position with respect to the chip). The results will be integrated into a demonstrator that performs an automated procedure that aligns a passive photonic chip with a terminal that contains the active components. The demonstrator is successful if adequate optical coupling of the passive photonic chip with the external active components is realized fully automatically, without the need of operator intervention.
What if living organisms communicated signals from the environment to us and thereby offered a sustainable alternative to electronic sensors? Within the field of biodesign, designers and scientists are collaborating with living organisms to produce new materials with ecological benefits. The company Hoekmine, in collaboration with designers, has been researching the potential of flavobacteria for producing sustainable colorants to be applied on everyday products. These non-harmful bacteria can change their form, texture and iridescent color in response to diverse environmental factors, such as humidity and temperature. Here, billions of cells are sensing and integrating the results as color. Therefore, Hoekmine envisions biosensors, which would minimize the use of increasingly demanded electronic sensors, and thus, the implementation of scarce and toxic materials. Developing a living sensor by hosting flavobacteria in a biobased and biodegradable flexible material offers opportunities for sustainable alternatives to electronic sensors. Aiming to take this concept to the next level, we propose a research collaboration between Avans, Hoekmine and a company specialized in biobased and biodegradable labels, Bio4Life. Together with this interdisciplinary team, we aim to bridge microbiology and embodiment design, and contribute to the development of a circular economy where digital technology and organic systems merge in the design of Living Circular Labels (LCLs). Throughout the project we will use an iterative approach between designing and testing LCLs that host living flavobacteria and additionally, methods for the end user to activate the bacteria’s growth at a given time.
Point-of-Care devices are broadly viewed as an important contribution to reduce the costs in our healthcare system. Cheap, quick, and reliable testing close to the point of need, can help early detection and thus reduce treatment costs, while improving the quality of life. An important challenge in the realization is the development of the individual cartridges that should be produced in large quantities at low costs. Especially for applications where high sensitivity is required, these cartrgidges will typically have a complex design. In this project we want to develop a manufacturing strategy for large scale production of cartridges based on photonic sensing chips, currently the most sensitive sensors available. A typical sensor cartridge with photonic sensors would comprise the sensor chip, an interface with active components (light source and detectors), the bio-active layer that captures the biomarkers to be detected and a protective package. In addition, there is the choice to integrate the active components in the package (making the interface an electrical one) or placing them in the read-out unit (making the interface an optical one). Finally, testing of the sensor cartridges should also be part of the process. A suitable manufacturing strategy would offer the lowest total-cost-of-ownership (TCO) of the production and use of the cartrdiges. Important in the considereations is that steps can be carried out at the wafer level, at the die level, and at the cartridge level. Because choices for a specific solution will strongly influence the possibilities for other steps, the development of a producitons strategy is far from straightforward. In this project we want to study the possibilities of the individual processes at the three levels mentioned (wafer, die, and cartridge), and in parallel develop a theoretical framework for finding the best strategy in this type of complex production processes.
