An important performance determinant in wheelchair sports is the power exchanged between the athletewheelchair combination and the environment, in short, mechanical power. Inertial measurement units (IMUs) might be used to estimate the exchanged mechanical power during wheelchair sports practice. However, to validly apply IMUs for mechanical power assessment in wheelchair sports, a well-founded and unambiguous theoretical framework is required that follows the dynamics of manual wheelchair propulsion. Therefore, this research has two goals. First, to present a theoretical framework that supports the use of IMUs to estimate power output via power balance equations. Second, to demonstrate the use of the IMU-based power estimates during wheelchair propulsion based on experimental data. Mechanical power during straight-line wheelchair propulsion on a treadmill was estimated using a wheel mounted IMU and was subsequently compared to optical motion capture data serving as a reference. IMU-based power was calculated from rolling resistance (estimated from drag tests) and change in kinetic energy (estimated using wheelchair velocity and wheelchair acceleration). The results reveal no significant difference between reference power values and the proposed IMU-based power (1.8% mean difference, N.S.). As the estimated rolling resistance shows a 0.9–1.7% underestimation, over time, IMU-based power will be slightly underestimated as well. To conclude, the theoretical framework and the resulting IMU model seems to provide acceptable estimates of mechanical power during straight-line wheelchair propulsion in wheelchair (sports) practice, and it is an important first step towards feasible power estimations in all wheelchair sports situations.
What will determine if power to gas will be an important technology in the energy transition over the next years? One can look at the development of a technology as a process that takes place in a technological innovation system (TIS). The TIS includes all actors and institutions that are involved in the development, diffusion and utilization of a technology. For a technology todevelop successfully the TIS should fulfil several functions. For power to gas technology several pilot projects are realized, studies are carried out and funds are available both for projects as for research. The functions called entrepreneurial activities, knowledge development, knowledge exchange and resource mobilization are all met. The function that faces the most problems iscalled market formation. There is not yet a regulatory framework for power to gas. Investors in power to gas also need to be rewarded for the benefits that they realize such as the avoided capital cost of extra infrastructure, the enabling of maximum utilization of renewable electricity and the increase in renewable content of the gas networks. Policy directed at market formation is therefor recommended.
In wheelchair sports, there is an increasing need to monitor mechanical power in the field. When rolling resistance is known, inertial measurement units (IMUs) can be used to determine mechanical power. However, upper body (i.e., trunk) motion affects the mass distribution between the small front and large rear wheels, thus affecting rolling resistance. Therefore, drag tests – which are commonly used to estimate rolling resistance – may not be valid. The aim of this study was to investigate the influence of trunk motion on mechanical power estimates in hand-rim wheelchair propulsion by comparing instantaneous resistance-based power loss with drag test-based power loss. Experiments were performed with no, moderate and full trunk motion during wheelchair propulsion. During these experiments, power loss was determined based on 1) the instantaneous rolling resistance and 2) based on the rolling resistance determined from drag tests (thus neglecting the effects of trunk motion). Results showed that power loss values of the two methods were similar when no trunk motion was present (mean difference [MD] of 0.6 1.6 %). However, drag test-based power loss was underestimated up to −3.3 2.3 % MD when the extent of trunk motion increased (r = 0.85). To conclude, during wheelchair propulsion with active trunk motion, neglecting the effects of trunk motion leads to an underestimated mechanical power of 1 to 6 % when it is estimated with drag test values. Depending on the required accuracy and the amount of trunk motion in the target group, the influence of trunk motion on power estimates should be corrected for.
MUSE supports the CIVITAS Community to increase its impact on urban mobility policy making and advance it to a higher level of knowledge, exchange, and sustainability.As the current Coordination and Support Action for the CIVITAS Initiative, MUSE primarily engages in support activities to boost the impact of CIVITAS Community activities on sustainable urban mobility policy. Its main objectives are to:- Act as a destination for knowledge developed by the CIVITAS Community over the past twenty years.- Expand and strengthen relationships between cities and stakeholders at all levels.- Support the enrichment of the wider urban mobility community by providing learning opportunities.Through these goals, the CIVITAS Initiative strives to support the mobility and transport goals of the European Commission, and in turn those in the European Green Deal.Breda University of Applied Sciences is the task leader of Task 7.3: Exploitation of the Mobility Educational Network and Task 7.4: Mobility Powered by Youth Facilitation.
In tijden van toenemende culturele diversiteit en arbeidsonzekerheid hebben jongeren in Nederlandse en Duitse stadswijken grote behoefte aan richting met betrekking tot hun toekomstige leven. Ouders en leraren lijken zelf vaak te worden overweldigd door de snel veranderende wereld waarin ze leven. Naast deze veranderingen neemt het gebruik van sociale media sterk toe, waardoor de al bestaande generatiekloof nog groter wordt. Deze ontwikkelingen hebben grote gevolgen voor de levensloopperspectieven van jongeren en leiden er vaak toe dat ze meer dan ooit richting zoeken bij hun leeftijdgenoten. In plaats van dit te zien als een problematische situatie, is dit project erop gericht de netwerken van jongeren te gebruiken als bron voor verbetering van de stadswijken. Het basisidee is jonge adolescenten (in de leeftijd van 12-14 jaar) te empoweren via bepaalde leeftijdgenoten die al gerespecteerd, verantwoordelijk en stabiel in het leven staan. Deze ‘homies’ (vier Nederlandse en vier Duitse jongeren) worden getraind en begeleid door experts op het gebied van oplossingsgericht denken en inspirerende communicatie. Daarna gaan de homies aan de slag in hun eigen wijk, waar ze drie maanden actief zullen zijn. De meeste communicatie met hun leeftijdgenoten zal verlopen via mobiele communicatie en sociale medianetwerken. In het begeleidende onderzoek wordt een analyse gemaakt van de leefsituatie van jongeren in de geselecteerde wijken voor en na de tussenkomst van de homies. De homies houden zelf een (mobiel) dagboek bij dat inzicht zal bieden in hoe zij zelf de veranderingen bij de jongeren in hun wijk zien.
Many lithographically created optical components, such as photonic crystals, require the creation of periodically repeated structures [1]. The optical properties depend critically on the consistency of the shape and periodicity of the repeated structure. At the same time, the structure and its period may be similar to, or substantially below that of the optical diffraction limit, making inspection with optical microscopy difficult. Inspection tools must be able to scan an entire wafer (300 mm diameter), and identify wafers that fail to meet specifications rapidly. However, high resolution, and high throughput are often difficult to achieve simultaneously, and a compromise must be made. TeraNova is developing an optical inspection tool that can rapidly image features on wafers. Their product relies on (a) knowledge of what the features should be, and (b) a detailed and accurate model of light diffraction from the wafer surface. This combination allows deviations from features to be identified by modifying the model of the surface features until the calculated diffraction pattern matches the observed pattern. This form of microscopy—known as Fourier microscopy—has the potential to be very rapid and highly accurate. However, the solver, which calculates the wafer features from the diffraction pattern, must be very rapid and precise. To achieve this, a hardware solver will be implemented. The hardware solver must be combined with mechatronic tracking of the absolute wafer position, requiring the automatic identification of fiduciary markers. Finally, the problem of computer obsolescence in instrumentation (resulting in security weaknesses) will also be addressed by combining the digital hardware and software into a system-on-a-chip (SoC) to provide a powerful, yet secure operating environment for the microscope software.
