Javelin throwing in the winter is not fun when the temperature approaches zero degrees. That is way javelin throwers move indoors for training. The problem with training indoors it that there is no room to throw a javelin 80 meters, so a different type of training is used. The javelin fitted with a rubber tip is thrown into a net. This way, the technique can still be practiced without the javelin’s flight. Unfortunately, the flight of the javelin can tell a lot about how well the javelin is thrown. Without that feedback, it is hard to know if an improvement in technique also results in a better throw. This project aims the fill that gap and provides performance feedback to the javelin thrower and the coach. Javelin throwing context First, the javelin throwing context is analyzed. The most critical parameters for measuring the performance of an athlete are the release velocity, release angle, and angle of attack. These parameters need to be measured with an accuracy of 0,25 m/s for the velocity and 1,5 degrees for both angles to give a realistic indication for the performance of the throw. The feel of the javelin is also crucial. It should hold the same as a standard javelin and should behave the same way when moving it around. Sports data collection The most used data collection now in day to day training is video recording, which can be played back in slow motion to dissect the technique of the athlete. As mentioned before, this does not tell everything about the performance of the throw. Several 3D tracking technologies are explored to find the best way the tracking the velocity and angles of the javelin. The best option seems to be a combined system of an inertial measurement unit inside the javelin with video tracking as an external reference system. The video can also be used to playback the recording of the throw. This way, the link between the technique and the performance of the throw becomes more apparent. Development For both the inertial measurement unit and the video tracking a proof of concept prototype is developed. The systems are combined to use the strengths of one system to fill in the weakness of the other. In this case, the video tracking can compensate for the drift of an inertial measurement unit, and the inertial measurement unit can reduce the noise in the video tracking data. Product A product name PRODON in build around the two tracking systems. It has active trackers front and back for the video tracking system to pick up. The inertial measurement unit is built into the back in a protective casing. The PRODON uses an app to communicate the collected performance data to the athlete and coaches. Combined with a video of throw, this can be a meaningful addition to indoor javelin training. Evaluation The accuracy of the prototype is tested in the situation where the javelin is thrown perpendicular to the camera. The velocity error calculated from this test is 0,02 m/s. The angle error tested came out to be 0,5 degree. Although these measurements fall below the set requirements, they are tested in a controlled 2D environment. Further testing in real conditions is needed to say for sure that this technology can provide accurate data.

The Nederlands Fotomuseum is the Dutch national museum for photography and its archive has the biggest collection of photographic material in the country. Currently, the visitors of the museum have a rather passive role and are merely subjected to the visual artworks in the museum. The museum desires to give the visitors more insight in the world behind photography, such as the photographic process, the invention and developments of the photo camera or the process of developing photographs in the dark room. This project explores the possibilities to let the visitors of the Nederlands Fotomuseum experience the world behind photography in an active, co-participatory way. First an analysis of the context is made: The museum’s vision, goals and ways of working. The way other museums handle interactive, educative installations. The desires of the visitors and motivation for coming. The way photographers work and what they desire. The principles of the photo camera. This is followed by an exploration of three promising scopes. Resulting from the analysis, the design goal is re-defined as: “Design an educational interactive experience for the visitor of the Nederlands Fotomuseum with a rechargers motive and no experience with photography. This experience needs to make this target group take a longer and better educated look at photographs to let them experience what it is like to be a photographer and what it takes to make a photograph”. The developing stage shows the creative process towards coming up with a design proposal fulfilling the design goal and meeting the requirements. This is done through a process of ideation, conceptualization and validation. Next, the design proposal is given, consisting of a presentation of the total design, an explanation of the envisioned co-participatory interaction, and a more detailed design of the mechanical part of the design proposal. Finally, the project is concluded by evaluating the design proposal on the requirements, discussing the feasibility, desirability and viability, and posing the recommendations for further research and development.