Domain
Categories
Amplified piezo actuators enhancement for active vibration control
7 June 2018
Amplified Piezo Actuators (APA®) from CEDRAT TECHNOLOGIES are known to be compact and especially performing in dynamic applications. The recent evolutions realized on the APA® and drive electronics allow them to address active damping better than magnetic proof mass in terms of the Force to Volume ratio above some 10Hz. The dynamic capability of the APA® has been improved thanks to preload method enhancement. Research has successfully shown the possibility to achieve a high dynamic force level similar to the static blocked force of the piezo actuator. This technical progress coupled with an amplified motion makes possible the generation of high mechanical proof mass load at relatively low frequency. It produces a force higher than 100N in a volume of Ø40x75mm within a range of [100-300Hz]. This paper presents relevant uses of APA® for active damping in machining applications. Several machining case studies are reported integrating Amplified Piezo
Actuators within the spindle head, inside the cutting tool or beside the workpiece clamp.
Cryogenic piezo characterisation and integration For Fine Steering Tip/Tilt Mechanism
19 June 2023
High precision cryogenic applications are demanding domains that require precise knowledge of component performance. In the case of active components such as piezoelectric actuators, such knowledge includes stroke, capacitance and Coefficient of Thermal Expansion (CTE). These parameters are difficult to define with precision because of the combination of small displacements and low temperature sensor compatibilities. A high stability and low sensibility test bench is required to obtain such results
Magnetically actuated fast steering mirrors
19 June 2023
Free-Space Optics (FSO) for optical communication request new compact low-power high-stroke high-bandwidth Fast
Steering Mirrors (FSM). To address this need, CEDRAT TECHNOLOGIES has developed a Magnetically-actuated Fast
Steering Mirror called M-FSM, taking heritage of its MICA™ actuators. This FSM offers Rx Ry strokes larger than +/-
2° with a 250Hz bandwidth when tilting a 31mm diam mirror. Requested power is minimized leading to low heating.
Vibration tests have been performed to define first limits and conditions for the M-FSM to bear external vibrations. Large
bandwidth closed loop control is achieved using integrated eddy current sensor and a state feedback-based controller.
Frequency Dependence of Mouse Brain Tissue Stiffness Measured in vivo with MR Elastography
19 June 2023
Magnetic resonance elastography (MRE) is a non-invasive imaging technique for quantitative measurement of the mechanical properties of biologic tissue in vivo [1]. The clinical interest in MRE has largely been driven by the direct relationship between tissue health and stiffness. As a result, MRE may provide significant clinical value for the non-invasive diagnosis of pathology and response to therapy by tracking tumor development and monitoring therapeutic response. MRE may also have considerable value in the development of treatment protocols in pre-clinical, rodent models of cancer. Because of cost and versatility, the mouse, in particular, is widely employed in oncologic studies. To resolve its small anatomic features, MRE experiments in mice must be performed with high driving frequencies (>600 Hz). However, high-frequency waves exhibit increased attenuation, reducing wave penetration depth and making it more difficult to impart motion deep into tissue with sufficient amplitude to overcome background noise. Also, biologic tissue is viscoelastic; hence, its response to load depends on the driving frequency. Recent MRE studies in mouse brain have been performed in high-field scanners (7 – 11.7T) at single driving frequencies of 1000 and 1200 Hz [2,3]. Here, we perform elastography in mouse brain tissue at 4.7T and report viscoelastic material properties over a range of driving frequencies (600 – 1800 Hz).
Design and evaluation of a piezo xy stage
19 June 2023
The ROSETTA/MIDAS mission of the Europeans Space Agency (ESA) intends to study the dust collected from the Wirtanen comet using an Atomic Force Microscope (AFM). This instrument utilzes an XY piezoelectric stage to achieve precise positioning in two in-plane orthogonal directions, and a Z actuator to support the needles for the analyses of dust particles in the out-of-plane direction.
From the Test Benches to the First Prototype of the muFly Micro Helicopter
19 June 2023
The goal of the European project muFly is to build a fully autonomous micro helicopter, which is comparable to a small bird in size and mass. The rigorous size and mass constraints infer various problems related to energy efficiency, flight stability and overall system design. In this research, aerodynamics and flight dynamics are investigated experimentally to gather information for the design of the helicopter’s propulsion group and steering system. Several test benches are designed and built for these investigations
