The rigid links are also printed by a 3D fused deposition modelling (FDM) printer with acrylonitrile butadiene styrene (ABS) as print material.
Also, whereas the MER valves are unstable (tending to oscillate) in certain transition temperature ranges, these valves are required not to oscillate. Dielectric elastomer (DE) membranes are able to self-deform with the application of an electric field through the thickness direction. The authors are not aware of any other vehicle in which a major actuator system was required to function throughout the complete re-entry profile while parts of the actuator were directly exposed to the ambient environment. With the best contact material actuators can be driven for more than 2700 h at 200 Hz with an electrical field strength of 20 V/m. An analysis conducted using the NASA/FLAGRO fracture mechanics computer program indicated that the actuator bracket might be a fracture critical component. Hydraulic hydrogel actuators and robots optically and sonically camouflaged in water, Yuk, Hyunwoo; Lin, Shaoting; Ma, Chu; Takaffoli, Mahdi; Fang, Nicolas X.; Zhao, Xuanhe, Active Flow Control Using Sweeping Jet Actuators on a Semi-Span Wing Model. In the frame of both projects, both types of the FAFC actuator concepts are addressed. This is the final report for the actuator bracket/lug fracture mechanics qualification test. Electrical connections to points A and B are used to apply electrical power in the resistive NiTi wire, causing a phase change that contracts the wire on the order of 5%.
The morphing capability of the wing relies on controlled deformation of the wing extrados under the action of shape memory alloys (SMA) actuators. The second objective, which is a direct consequence of the first, is to determine the approximate magnitude of errors committed by actuator model approximations of various fidelities. This emerging domain is characterized by continuous soft structures that simultaneously fulfill the role of robotic link and actuator, where prime focus is on design and fabrication of robotic hardware instead of software control. Each purge-fill-power cycle can be independent, allowing the actuator to readily tolerate misfires. We used the microgrippers to perform diverse functions, such as picking up a bead on a substrate and the removal of cells from tissue embedded at the end of a capillary (an in vitro biopsy). An important disadvantage of prior SMA wire actuators is relatively low cycle speed, which is related to actuation temperature as follows: The SMA wires in prior SMA actuators are typically made of a durable nickel/titanium alloy that has a shape-memory activation temperature of 80 C. An SMA wire can be heated quickly from below to above its activation temperature to obtain a stroke in one direction, but must then be allowed to cool to somewhat below its activation temperature (typically, less than or equal to 60 C in the case of an activation temperature of 80 C) to obtain a stroke in the opposite direction (return stroke). Finally, FDFM and maintainability improvements for dual tandem actuators were recommended. Others have attempted to modify pneumatic microvalves for portable applications, e.g., by transitioning to electromagnetic, thermopneumatic, or piezoelectric actuation principles.
Unlike the typical designs, where the valves are fully closed and perpendicular to the fluid flow direction, the valves are not fully closed in this design, where there is an attack angle between the valves and fluid flow. When flow is against the rod tilt direction, the rods bend backward, narrowing the channel and increasing flow resistance; when flow is in the direction of rod tilt, the rods bend forward, widening the channel and decreasing flow resistance. To solve the problem of the small deformation of PVs and improve the overall performance of PMPs, an FD PMP based on hydraulic amplification was designed, and its amplification unit was analyzed theoretically and tested experimentally. Over the past few decades, the developments in the Micro-electro-mechanical Systems (MEMS) technology have realized the implementation of microfluidic devices to a wide range of applications such as drug delivery systems [, According to the operation mechanism, micro-pumps are categorized in two branches: mechanical and non-mechanical micro-pumps. Each rotary actuator assembly includes a motor mounted about the respective axis, a gear drive rotatably connected to the motor, and a torsion spring. This work is the first stage prototype of a vehicle that will consist of many actuated body segments. The temperature to initiate the back bending is as low as ~240C. The devices are fabricated with the SOIMUMPs process developed by MEMSCAP, Inc. (Durham, NC, USA). By using templates, microchannel structures are replicated onto the surface of two highly elastic polymers, polyvinylidene fluoride (PVDF) and polyvinyl alcohol, to induce chiral coiling upon exposure to acetone vapors. The performance of a variety of different actuators was examined, including high polymer films, flextensional actuators, miniature speakers, unimorphs, and Rainbows. The actuators were piezoelectric benders manufactured using the THUNDER technology and were custom designed for the application. The device lies flat against the skull which would allow it to form the basis of a subcutaneous bone-anchored hearing aid. The effort to develop a smart patch involves both contractual and inhouse programs which are currently focused on miniaturization of the electronics associated with vibrational control using piezoceramic sensors and actuators. Depending on the mechanical setup, stack and roll actuators can be realized. The load on the motor can also be reduced, leading to a lower power consumption. Some hysteresis and nonlinearity are present, but repeatability is high. The maximum swimming speed of the fish robot was 7.7 cm/s at 3.9Hz tail-beat frequency. In this work, we designed and fabricated electrothermal air pump-type actuators by utilization of various nanostructured carbon materials, including single wall carbon nanotubes (SWCNTs), reduced graphene oxide (r-GO), and graphene oxide (GO)/SWCNT hybrid, Plasma actuators for bluff body flow control, The aerodynamic plasma actuators have shown to be efficient flow control devices in various applications. Microengineering of magnetic bearings and actuators. Design and demonstration of a fish robot actuated by a SMA-driven actuation system. Under an applied electric field, the torsional actuator produces large angular displacement and a high torque. and purchase. By functionalizing one arm of the hinge and the filament ends, the hinge can be attached to a surface while still allowing an arm to rotate and the filaments can be labeled with magnetic beads enabling the hinge to be actuated almost instantaneously by external magnetic fields. Stretchable Materials for Robust Soft Actuators towards Assistive Wearable Devices, Agarwal, Gunjan; Besuchet, Nicolas; Audergon, Basile; Paik, Jamie. Performance tests of the fish robot in water were carried out to measure tail-beat angle, thrust force, swimming speed and turning radius for tail-beat frequencies from 1Hz to 5Hz. ; Witkowski, W.R. Electrically controlled polymeric gel actuators or synthetic muscles are described capable of undergoing substantial expansion and contraction when subjected to changing pH environments, temperature, or solvent. The DOE results guided the selection of the design parameters for the final proof-of-concept actuator. Separated Flow Control with Actuated Membrane Wings. A miniature robot driven by a biomimetic actuation system with four 2-DOF (two-degree-of-freedom) legged mechanisms is realized. Crude properties of the actuator (e.g., peak mass rate and frequency) may be sufficient for some designs, while detailed information is needed for other applications (e.g., multiple actuator interactions). The passive chain, on the other hand, is attached to the active chain from one end and consists of two rigid links made of polymer. Paper Actuators Made with Cellulose and Hybrid Materials, Kim, Jaehwan; Yun, Sungryul; Mahadeva, Suresha K.; Yun, Kiju; Yang, Sang Yeol; Maniruzzaman, Mohammad, Recently, cellulose has been re-discovered as a smart material that can be used as sensor and actuator materials, which is termed electro-active paper (EAPap). The wearable wristband and chest patch may be used for low-cost, wireless and continuous sensing of skin hydration and other health parameters. Applications of Magpol can include artificial muscles, drug delivery, adaptive optics and self healing structures. Task 7A: Augmentor wing cruise blowing, Development of an automated high temperature, Combined planar imaging of schlieren photography with OH-LIPF and spontaneous OH-emission in a 2-D, A mechanical cell disruption microfluidic platform based on an on-chip, A micro-flow-batch analyzer with solenoid, Wireless programmable electrochemical drug delivery, Simulation of fluid-structure interaction in, Cylindrical Piezoelectric Fiber Composite, Active Joint Mechanism Driven by Multiple, Active joint mechanism driven by multiple, Telescoping cylindrical piezoelectric fiber composite, Cruise and turning performance of an improved fish robot, Design integration and noise studies for jet STOL aircraft. The results of this study provide insight that can be used to design and select the optimal sweeping jet actuator configuration for flow control applications. Furthermore, a FEA model of a DEAP film is presented, which is expanded to a multilayer DEAP stack-actuator model. The presentation focuses on the performances of flexible all-polymer electroactive actuators under space-hazardous environmental factors in laboratory conditions. EA's have certain characteristics which must be considered in their application. Soft actuators have attracted a lot of attention owing to their biomimetic performance. A mechanical cell disruption microfluidic platform based on an on-chip micropump.
The actuators were attached to a simple truncated shaped fin and the deflection angle was analysed in both air and liquid for excitation with +/- 1V square wave at a range of frequencies. During normal operation, only the electromechanical actuator is needed to operate a flight control surface. Someexamplesof resistiveactuatorsare thermal inkjet printers,electroosmoticpumps6,andshape, Mullette, Mark; Matthews, Gary; Russell, Kevin (Technical Monitor). Here, we study fluid-powered fiber-reinforced actuators, because these have previously been shown to be capable of producing a wide range of motions.
PROGRAM ELEMENTare used to derive power and energy storage requirements for control surface actuation during extreme submarine maneuvers, such as emergencyand for initially sizing system components. Tap water is used for both the liquid in the storage chamber and the test fluid. An actuator effectiveness index is developed and shown to be helpful in screening actuator locations in the structure. Chronopontentiograms for specific current, pH, and temperature values were obtained in electrolytes with different compositions. As indicated in the results, the maximum flow rate of the micro-pump depends on the design of its components and operation conditions. Although scaling down the actuator (based on the throat dimensions) from 0.25 inch x 0.125 inch to 0.15 inch x 0.075 inch resulted in similar flow control performance, scaling down the actuator further to 0.075 inch x 0.0375 inch reduced the actuator efficiency by reducing the coverage area and the amount of mixing in the near-wall region.
The multilayer actuator stacks fabricated from our piezoceramics are advantageous for sensing and high capacitance applications. Our numerical results show that the optimum attack angle can be predicted from the known width and length of the valve. Because the actuator is made of a flexible bag, it does not interfere with other actuators when it is depressurized. Choi, Sang H.; Golembiewski, Walter T.; Song, Kyo D. The concept of microwave-driven smart material actuators is envisioned as the best option to alleviate the complexity associated with hard-wired control circuitry. angle to an X and Z axis providing rotation of the actuator housing assembly about the Y axis. The actuators exploit the flexibility of silicone and the electric conductivity of iron oxide particles. Meller, M. A.; Tiwari, R.; Wajcs, K. B.; Moses, C.; Reveles, I.; Garcia, E. Hydraulic Artificial Muscles (HAMs) consisting of a polymer tube constrained by a nylon mesh are presented in this paper. Thermocouple for heating and cooling of memory metal actuators. During the experiments, it was found that DBD performance is severely limited by surface charge accumulation on the dielectric. A least squares fit of the model to experimental data showed Qd to increase with the cube of the force on the piston and linearly with the compression frequency. Thus the allowable region of actuators was determined. For The systematic methodology proposed in this study can be conveniently extended for the dynamic modeling and controller design of other planar flexible parallel manipulators, especially the emerging ones with multiple actuation modes. Flow reversed for shutdown. Actuator motion can be transmitted to the optical fiber by use of hinges and clamp blocks. Intelligent fault diagnosis and failure management of flight control actuation systems. The maximum strain of the composite showed an exponential dependence on the Ms. A bearing is used to transfer motion and smoothly transition from one state to another.
This paper presents a procedure for modeling structures containing piezoelectric actuators using MSCMASTRAN and MATLAB. The circular serpentine, square serpentine and spanwise actuators have subharmonic sinuous streak breakdown and behave like oblique wave transition scenario. A small biomimetic quadruped robot driven by multistacked dielectric elastomer actuators, Nguyen, Canh Toan; Phung, Hoa; Dat Nguyen, Tien; Lee, Choonghan; Kim, Uikyum; Lee, Donghyouk; Moon, Hyungpil; Koo, Jachoon; Nam, Jae-do; Ryeol Choi, Hyouk. A tension stiffened and tendon actuated manipulator is provided performing robotic-like movements when acquiring a payload.
With suitable synthetic and preparation pathways and well-controlled actuation stimuli, such as heat, light, electric and magnetic fields, excellent physical properties of LCE materials can be realized. Gang, and H. F. Zhi, , J. T. Bharambe, P. W. Mogal, and S. Patil, , J. H. Yoo, J. Sirohi, and N. M. Wereley, , Z. Zhang, J. Kan, S. Wang, H. Wang, J. Ma, and Y. Jiang, , Z. G. Yang, D. Y. Liu, L. P. Wu, H. T. Chen, and P. Liu, , Y. F. Dong, X. T. Qu, J. S. Dong, and H. W. Zhao, , Y. Wu, Z. G. Yang, Y. Liu, X. Y. Wang, and L. Liu, , This option allows users to search by Publication, Volume and Page. Slow actuation, low load capacity, sterilization difficulties, leaking electricity and transferring produced heat to tissues, and high cost are among the key limitations of the use of electric motors in in-vivo applications. To develop an understanding of the influences of key design parameters on the actuator response time and displacement amplitude, a half-factorial 25 Design of Experiment (DOE) study was conducted utilizing eight differently configured prototypes. Simulations demonstrate effective pumping even at Reynolds numbers as low as 0.001. Downloaded binary data controls the applied voltage and modulation frequency for each actuator, and High Voltage MOSFETs are used to activate them.
Plasticized PVC gel which has a large deformation by applying a voltage and high driving stability in the atmosphere is considered as a suitable candidate material for development of soft actuator. The PMP driving signal is generated by the driving power of the SDVC31-S PV. The measurements on the smaller actuators have been repeated and agreed with the previously reported values within +/- 10%. An application of lab fabricated HAMs for a meso-scale robotic system is also presented. Their electrochemical actuation potential is demonstrated in this study. PMID:24385868. Soft actuators are the components responsible for producing motion in soft robots.
As a matter of fact, the scientific literature reports only theoretical uses of such actuators, but, in practice it does not seem they were ever used. When the other SMA is heated the action is reversed. The actuation performance, strain hysteresis, and heat generation of the shear-bending mode actuators based on soft and hard BiScO3-PbTiO3 (BS-PT) ceramics were investigated under different thermal (from room temperature to 300 C) and electrical loadings (from 2 to 10 kV/cm and from 1 to 1000 Hz). 37 figs. Design optimization of an electromagnetic actuation based valveless micropump for drug delivery application. To sign up for alerts, please log in first. The beams can be heated by methods including the passage of an electrical current through them.
Because the actuator is made of a flexible bag, it does not interfere with other actuators when it is depressurized. The two outer members would also be piezoelectric; the release of the clamps on the upper or lower end would be achieved by applying a voltage to the electrodes on the upper or lower ends, respectively, of these members. Schiller, Noah H.; Cabell, Randolph H.; Quinones, Juan D.; Wier, Nathan C. A helicopter structure experiences substantial high-frequency mechanical excitation from powertrain components such as gearboxes and drive shafts.
Task 7A: Augmentor wing cruise blowing valveless system.
These actuators gave fast operation in air (to 90 Hz), and were utilised as active flexural joints on the tail fin of a fishshaped floating "boat". Modifications directed toward ensuring reliable and predictable operation during planned 12-year cruise and interval of hard use at end of cruise. Other embodiments feature two prime movers driving separate linear spindle screw transmissions, one internal and one external, in a totally concentric and compact integrated module. There are a number of actuators using the deformation of electroactive polymer (EAP), where fewer papers seem to have focused on the performance of 3D morphing actuators based on the analytical approach, due mainly to their complexity. However, due to the slow actuation speed of SMAs, there are limitations in their range of possible applications.
Implementing programmable actuation into materials and structures is a major topic in the field of smart materials. Spherical motors perform all three actuation functions, i.e., three DOF, with only one moving part. Advanced high performance vertical hybrid synthetic jet actuator, Xu, Tian-Bing (Inventor); Jiang, Xiaoning (Inventor); Su, Ji (Inventor). Actuator development for the Instrument Pointing System (IPS). 
A new rotary MEMS actuator has been developed and tested at Sandia National Laboratories that utilizes a linear thermal actuator as the drive mechanism. The implementation of the MEMS technology gives rise to generate high-efficiency microfluidic tools for satisfying the needs in the biomedical industry. In this work we present recent progress in mimicking these photo-actuating systems through remote light exposure of a metastable state photoacid and the resulting signal and energy transfer through solution to a pH-responsive hydrogel actuator. Existing AI approaches and applications of FDFM were examined and evaluated. The proposed microsystem using solenoid micro-pumps presented satisfactory robustness and high sampling rate (190 h(-1)), with satisfactory reproducibility (relative standard deviation <4.5%, n=3), low reagents consumption (32 L per analysis) and cost to build the device. In the event of system failure, a run-away actuator was prevented by an improved braking device which arrests the mechanism. Electric power is applied simultaneously to the elements. The working principle of the full actuator will then be given. Cheng, Yinuo; Wang, Yue; Wang, Zhiyuan; Huang, Liang; Bi, Mingzhao; Xu, Wenxiao; Wang, Wenhui; Ye, Xiongying. Bi-stable optical element actuator device. Another Lesson from Plants: The Forward Osmosis-Based Actuator, Osmotic actuation is a ubiquitous plant-inspired actuation strategy that has a very low power consumption but is capable of generating effective movements in a wide variety of environmental conditions. The AFC results using the smaller actuators show that while the actuators can control flow separation, the selected spacing of 3.3 cm may be too large due to the reduced sweep angle. A series of uniform composites was prepared by dispersing purified single wall nanotubes with varying weight percents into a polymer matrix, followed by solution casting. To meet the NASA goal to reduce the actuators size, mass, cost and power consumption, electroactie polymers (EAP) are being developed to induce large bending and longitudinal actuation strains. These recovery forces are used for actuation. Experimental evidence shows that this controller can control the soft actuator to track the desired trajectories effectively. Each capstan is capable of rotating the shaft. Typically, the biasing is based on elastomer pre-stretch or on dead loads, which results in relatively low actuation strain. (Inventor); Pearson, David D. (Inventor); Dreitlein, Kenneth C. (Inventor); Loffredo, Constantino V. (Inventor). The shape control equation in finite element formulation of the cantilever beam partially covered with dielectric elastomer actuators is derived based on the constitutive equation of dielectric elastomer material by using Hamilton principle. Our efforts include modeling of the hysteresis behavior of the actuator. Actuator movement using one or more ranges of motion is utilized to control motion to position an actuating element in three dimensional space. Shi, H.; Zhao, Y.; Liu, Z. Initial indications are that actuator reliability is excellent, with no actuator failures or large net reduction in actuator performance. A silicon-on-insulator MEMS process has been employed for the fabrication of these micromirrors. The actuator further includes a passive element disposed between the flexible members to tune a stiffness characteristic of the actuator. We present a fully integrated implantable electrolysis-based micropump with incorporated EI dosing sensors. 
