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Low-cost sensors provide a unique opportunity to continuously monitor patient progress during rehabilitation; however, these sensors have yet to demonstrate the fidelity and lack the calibration paradigms necessary to be viable tools for clinical research. The purpose of this study was to validate a low-cost wearable sensor that accurately measured peak knee extension during clinical exercises and needed no additional equipment for calibration. Sagittal plane knee motion was quantified using a 9-axis motion sensor and directly compared to motion capture data. The motion sensor measured the field strength of a strong earth magnet secured to the distal femur, which was correlated with knee angle during a simple calibration process. Peak knee motions and kinematic patterns were compared with motion capture data using paired t-tests and cross correlation, respectively. Peak extension values during seated knee extensions were accurate within 5 degrees across all subjects (root mean square error: 2.6 degrees, P = 0.29). Knee flexion during gait strongly correlated (0.84 ≤ rxy ≤ 0.99) with motion capture measurements but demonstrated peak flexion errors of 10 degrees. In this study, we present a low-cost sensor (≈$ 35 US) that accurately determines knee extension angle following a calibration procedure that did not require any other equipment. Our findings demonstrate that this sensor paradigm is a feasible tool to monitor patient progress throughout physical therapy. However, dynamic motions that are associated with soft-tissue artifact may limit the accuracy of this type of wearable sensor.

Functional outcomes, such as joint flexion and gait, are important indicators of efficacy in musculoskeletal research. Current technologies that objectively assess these parameters, including visual tracking systems and force plates, are challenging to deploy in long-term translational and clinical studies. To that end, we developed a wearable device that measures both physical activity and joint flexion using a single integrated sensor and magnet system, and hypothesized that it could evaluate post-operative functional recovery in an unsupervised setting. To demonstrate the feasibility of measuring joint flexion, we first compared knee motion from the wearable device to that acquired from a motion capture system to confirm that knee flexion measurements during normal human gait, predicted via changes in magnetic field strength, closely correlated with data acquired by motion capture. Using this system, we then monitored a porcine cohort after bilateral stifle arthrotomy to investigate longitudinal changes in physical activity and joint flexion. We found that unsupervised activity declined immediately after surgery, with a return to pre-operative activity occurring over a period of 2 weeks. By providing objective, individualized data on locomotion and joint function, this magnet-based system will facilitate the in vivo assessment of novel therapeutics in translational orthopaedic research.

Functional outcomes, such as joint flexion and gait, are important indicators of efficacy in musculoskeletal research. Current technologies that objectively assess these parameters, including visual tracking systems and force plates, are challenging to deploy in long-term translational and clinical studies. To that end, we developed a wearable device that measures both physical activity and joint flexion using a single integrated sensor and magnet system, and hypothesized that it could evaluate post-operative functional recovery in an unsupervised setting. To demonstrate the feasibility of measuring joint flexion, we first compared knee motion from the wearable device to that acquired from a motion capture system to confirm that knee flexion measurements during normal human gait, predicted via changes in magnetic field strength, closely correlated with data acquired by motion capture. Using this system, we then monitored a porcine cohort after bilateral stifle arthrotomy to investigate longitudinal changes in physical activity and joint flexion. We found that unsupervised activity declined immediately after surgery, with a return to pre-operative activity occurring over a period of 2 weeks. By providing objective, individualized data on locomotion and joint function, this magnet-based system will facilitate the in vivo assessment of novel therapeutics in orthopaedic research.

In this work, we have developed a design environment to allow casual users to quickly and easily create custom robots. A drag-and-drop graphical interface allows users to intuitively assemble electromechanical systems from a library of predesigned parametrized components. A script-based infrastructure encapsulates and automatically composes mechanical, electrical, and software subsystems based on the user input. The generated design can be passed through output plugins to produce fabrication drawings for a range of rapid manufacturing processes, along with the necessary firmware and software to control the device. From an intuitive description of the desired specification, this system generates ready-to-use printable robots on demand.

Recent advances in design, fabrication, and programming technologies enable the rapid digital manufacturing of functional robotic systems. Novices can quickly fabricate mechanical frames thanks to 3D printers and cut-and-fold techniques and quickly program the control behavior of a robot using modern software environments. However, there is still not a systematic way to design custom printed circuit boards (PCB). In this work, we propose a hierarchical approach that allows casual users to quickly and easily create PCBs. A drag-and-drop graphical interface allows users to intuitively assemble PCBs from a library of predesigned, parameterized components, and a script-based infrastructure automatically composes all of the electronic systems based on user inputs. The final output is a fabrication-ready electronic design. Within this framework, we also propose a verification analysis that allows the user to quickly check that the developed design conforms to electrical constraints like voltage, current, and power limitations. Finally, we validate the proposed co-design environment with experimental results through the realization of a teleoperated segway robot.Copyright © 2015 by ASME

Diskussionsbeitrag zu:El-Mossallamy, Y., Loschner, J. : Beitrag zur Standsicherheit von Boschungen nach DIN 1054 – Januar 2005. Bautechnik 83 (2006), S. 288–289.

Variable valve trains play an important part in enhancing engine efficiency. In order to gain maximum benefit from this, thorough concept optimisation has to be carried out in advance. This task is ideally performed by means of engine simulation.

The mid-sized gasoline engine family by Fiat-GM Powertrain, internally called Family 1, was redesigned for improved fuel consumption, exhaust emissions, quality, maintenance and manufacturing cost. In addition to the optimizations the refinement focused on the modular use of components.

Die mittlere Ottomotoren-Baureihe von Fiat-GM Powertrain, intern als Familie 1 bezeichnet, wurde grundlegend hinsichtlich Kraftstoffverbrauch, Emissionsreduzierung, Qualitat, Wartungsaufwand und Herstellkosten uberarbeitet. Neben den Optimierungen stand die Modularisierung der Komponenten im Mittelpunkt.

We propose a simplified high-level programming language based on blocks and links dragged on a workspace which generates the skeleton code for robotic applications involving different types of robots. In order to develop such a high-level programming language that still can guarantee flexibility in term of implementation, our approach takes advantage of the robot operating system (ROS). ROS is a open source meta-operating system that provides a message passing structure between different processes (or nodes) across a network (inter-process communication). In our framework, we consider a hierarchical approach in which at the base there is ROS that allows inter-process communication between nodes in a robot and on the top we create a high-level language that interacts with ROS and thus with the real robot. The high-level language can be viewed as an extra layer added to simplify lower level code generation.

Observing the success of the open source software movement, the Adaptive Vehicle Make (AVM) is a program run by the Defense Advanced Project Agency (DARPA) with the goal of applying crowd-sourced and component-based engineering to the design of military vehicles. In this paper, we present a credentialing system called TrustForge, which enables effective and flexible access control for the AVMcrowd-sourced repository. Credentialing systems are essential in crowdsourcing to ensure quality, since it is potentially open to contributions made by anyone. The open source software community has developed elaborate manual approaches of managing its contributor community, which are often very labor-intensive and inefficient. Our aim with TrustForge is to improve the automation of the credentialing and access control process in the context of component-based systems, where users contribute components at various levels of abstraction. TrustForge takes a hybrid approach that combines trust policy and reputation to address this problem. In TrustForge, a policy language is used to specify the access control rules for users in the system to contribute components. In addition, reputation values computed for users based on the quality of their past component contributions are used to tune the static policies to enable flexibility and adaptiveness. The contributions of this work are as follows: (1) the design of TrustForge - an effective and flexible access control mechanism that combines policy and reputation approaches; (2) the identification of heuristics for component quality measurement and a novel reputation computation algorithm for evaluating user trustworthiness; (3) a data model based on provenance graphs that allows efficient repository information storage and retrieve. We have implemented TrustForge system and integrate it with the VehicleForge repository system to support the operation of the AVM challenge program. The evaluation results based on realworld deployment and systematic simulation demonstrate that TrustForge can effectively discern the trustworthiness of users within the crowd-sourced system.

The small gasoline engine family by Fiat-GM Powertrain, internally called Familiy 0 -Ecotec, has been optimized with respect to fuel consumption and emission by introducing the Twinport-Technology. Furthermore the displacement of the 2nd generation of this engine family was enlarged and improvements in quality, maintenance and manufacturing cost have been achieved.

Virtual development is an inherent part of the product development process. To put virtual development into effect the simulated vehicle has to be experienced and rated. Simulators are established to rate the virtual vehicles. A method is presented that demonstrates how the requirements for a comfort simulator can be satisfied. The main part is the realisation of the excitation of the steering wheel. The results that can be achieved with this simulator are discussed and the validity is proven.

Holography is an imaging method based on the interference ability of coherent light. Apart from artistic and commercial applications, holograms are often used as storage media in databank systems and in devices for optical measurement.