T a new major technological advance is available that can help control-valve users avoid many of the problems and inefficiencies associated with using compressed air as a power medium. The new solution uses electric power and eliminates dependence on compressed air. This totally electric solution is appropriate and cost-effective for a wide variety of control-valve applications, including those...

This paper presents the design of a magnetic resonance imaging (MRI) compatible pneumatic actuator regulated by piezoelectric valve for image guided robotic intervention. After comparing pneumatic, hydraulic and piezoelectric MRI compatible actuation technologies, we present a piezoelectric valve regulated pneumatic actuation system consisted of PC, custom servo board driver, piezoelectric valv...

The effects of spark timing and exhaust valve timing change on exhaust gas temperature during cold start of an SI engine are studied through engine bench tests. It is observed that the exhaust gas temperature increases when the spark timing and valve timing are retarded individually or simultaneously, due to late combustion or slow flame speed. However, using COVimep it is also investigated tha...

Modern engines have an increasing number of control parameters that are having a dramatic impact on calibration time. Up-front prototyping of calibration processes can be used to reduce the burden of increasing powertrain complexity, however, such techniques are still in their infancy in the automotive field. In this paper we illustrate how flexible model-based calibration tools can be used to ...

At partial load, traditional automotive gasoline engines have high pumping losses due to the throttling of intake charge for load control. Variable Valve Timing (VVT) and introduction externally cooled EGR could reduce but only with a very limited effect. On other hand, in medium full range, engine cannot utilize compression ratio limitations knocking. A variable displacement, device which util...

Hydrogels, i.e., water-swollen polymer networks, have been studied and utilized for decades. These materials can either passively support mass transport, or can actively respond in their swelling properties, enabling modulation of mass and fluid transport, and chemomechanical actuation. Response rates increase with decreasing hydrogel dimension. In this paper, we present three examples where in...

The MIT Faculty has made this article openly available. Please share how this access benefits you. Your story matters. This paper presents the design, analysis and experimental testing of a variable-pitch quadrotor. A custom in-lab built quadrotor with on-board attitude stabilization is developed and tested. An analysis of the dynamic differences in thrust output between a fixed-pitch and varia...