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I regeringsuppdraget ingår också att bedöma vilken typ av materialåtervinning av textilier som kan komma till stånd på kort och lång sikt och hur det bör påverka utformningen av insamlingssystemet. Naturvårdsverket gav därför i uppdrag till SP Sveriges Tekniska Forskningsinstitut att kartlägga befintlig teknik och aktuella utvecklings- och forskningsinitiativ samt att utföra en kvalificerad bedömning om möjlig framtida teknisk utveckling inom området textil materialåtervinning. I forskarstudien analyseras tekniska och miljömässiga utmaningar samt potentialen för textilåtervinning. Utifrån textilåtervinningens tekniska och miljömässiga förutsättningar ges rekommendationer för hur utmaningar kan bemötas och miljövinsten med materialåtervinning optimeras. Bedömningarna och rekommendationerna baseras på livscykelanalyser av olika scenarier för hur återvinningen kan ske.

The research presented in this thesis describes a substantial part of the design of a prototypical surgical training simulator. The results are intended to be applied in future simulators used to educate and train surgeons for bone milling operations. In earlier work we have developed a haptic bone milling surgery simulator prototype based on three degrees-of-freedom force feedback. The contributions presented here constitute an extension to that work by further developing the haptic algorithms to enable six degrees-of-freedom (6-DOF) haptic feedback. Such feedback is crucial for a realistic haptic experience when interacting in a more complex virtual environment, particularly in milling applications.The main contributions of this thesis are:The developed 6-DOF haptic algorithm is based on the work done by Barbic and James, but differs in that the algorithm is modified and optimized for milling applications. The new algorithm handles the challenging problem of real-time rendering of volume data changes due to material removal, while fulfilling the requirements on stability and smoothness of the kind of haptic applications that we approach. The material removal algorithm and the graphic rendering presented here are based on the earlier research. The new 6-DOF haptic milling algorithm is characterized by voxel-based collision detection, penalty-based and constraint-based haptic feedback, and by using a virtual coupling for stable interaction.Milling a hole in an object in the virtual environment or dragging the virtual tool along the surface of a virtual object shall generate realistic contact force and torque in the correct directions. These are important requirements for a bone milling simulator to be used as a future training tool in the curriculum of surgeons. The goal of this thesis is to present and state the quality of a newly developed 6-DOF haptic milling algorithm. The quality of the algorithm is confirmed through a verification test and a face validity stud, QC 20120226