Robots are now moving from their conventional confined habitats such as factory floors to human environments where they assist and physically interact with people. The requirement for inherent mechanical safety is overarching in such human-robot interaction systems. We propose a dual actuator called Parallel Force/Velocity Actuator (PFVA) that combines a Force Actuator (FA) (low velocity input) and a Velocity Actuator (VA) (high velocity input) using a differential gear train. In this arrangement mechanical safety can be achieved by limiting the torque on the FA and thus making it a backdriveable input. In addition, the kinematic redundancy in the drive can be used to control output velocity while satisfying secondary operational objectives. Our research focus was on three areas: (i) scalable parametric design of the PFVA, (ii) analytical modeling of the PFVA and experimental testing on a single-joint prototype, and (iii) generalized model formulation for PFVA-driven serial robot manipulators. In our analysis, the ratio of velocity ratios between the FA and the VA, called the relative scale factor, emerged as a purely geometric and dominant design parameter. Based on a dimensionless parametric design of PFVAs using power-flow and load distributions between the inputs, a prototype was designed and built using commercial-off-the-shelf components. Using controlled experiments, two performance-limiting phenomena in our prototype, friction and dynamic coupling between the two inputs, were identified. Two other experiments were conducted to characterize the operational performance of the actuator in velocity-mode and in what we call ‘torque-limited’ mode (i.e. when the FA input can be backdriven). Our theoretical and experimental results showed that the PFVA can be mechanical safe to both slow collisions and impacts due to the backdriveability of the FA. Also, we show that its kinematic redundancy can be effectively utilized to mitigate low-velocity friction and backlash in geared mechanisms. The implication at the system level of our actuator level analytical and experimental work was studied using a generalized dynamic modeling framework based on kinematic influence coefficients. Based on this dynamic model, three design case studies for a PFVA-driven serial planar 3R manipulator were presented. The major contributions of this research include (i) mathematical models and physical understanding for over six fundamental design and operational parameters of the PFVA, based on which approximately ten design and five operational guidelines were laid out, (ii) analytical and experimental proof-of-concept for the mechanical safety feature of the PFVA and the effective utilization of its kinematic redundancy, (iii) an experimental methodology to characterize the dynamic coupling between the inputs in a differential-summing mechanism, and (iv) a generalized dynamic model formulation for PFVA-driven serial robot manipulators with emphasis on distribution of output loads between the FA and VA input-sets. / text

Today there are no requirements on burglary protection in the building regulation “Boverketsbyggregler”. Instead SSF Stöldskyddsföreningen has developed norms for physical security.SSF 200:5 is a norm that treats burglary protection in buildings and business premises, and isused as a basis for the insurance companies own description of security classification.The main purpose of the report is to get an increased understanding of what requirementsregarding burglary protection there are, and who is demanding them. The report also aims toexplore how people in the industry deal with security related work in the design stage.The questions at issue are all related to burglary protection. To answer these questions threemethods have been used. Interviews/surveys, physical tests, and a comparison between SSF200:5 and the insurance companies description of security classification.The interviews show that the burglary protection can vary depending on who the claimant is.It shines a light on a problem that occurs in the construction process, that is, discussingsecurity related questions too late. This can lead to compromised burglar security andincreased construction costs.The comparison shows that SSF 200:5 is not fully comparable with the insurance companiesdescription of security classification. Easy measures like door and window locks can beequated, meanwhile more complicated measures like wall constructions, can not.Using the test results, alternative wall constructions that satisfy the norm have been presented.Also improvements of SSF 200:5 have been discussed in favor of the whole industry.