首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 78 毫秒
1.
This paper proposes to employ multi-dimensional controller for driving LED backlight scanning in a 120 Hz LCD for overcoming the hold-type characteristic of an LCD in time-multiplexed stereoscopic displays. A synchronization signal circuit is developed to connect the time scheme of the vertical synchronization for reducing scanning time. The general strategy is to integrate 3D controller and all relatively small-signal electronic functions into one ASIC to minimize the total number of the components. The display panel, LED backlight scanning, and shutter glass signals could be adjusted by vertical synchronization and modulation to obtain stereoscopic images. Each row of LED in a backlight module is controlled by multi-dimensional data registration and synchronization control circuits for LED backlight scanning to flash in bright or dark. LED backlight scanning stereoscopic display incorporated with shutter glasses is provided to realize stereoscopic images even viewed in a liquid crystal display. The eye shutter signal is alternately switched from the left eye to the right eye with 120 Hz of LCD Vertical synchronization (V-sync). This kind of low cross-talk shutter glasses stereoscopic display with an intelligent multiplexing control of LED backlight scanning has low cross-talk below 1% through a liquid crystal shutter glasses.  相似文献   

2.
A novel low‐power gate driver architecture was developed for large 8 K 120 Hz liquid crystal display panel. For this application, not only high‐speed driving but also low power consumption is required. We employed a high mobility In‐Ga‐Zn‐O, dual VGL level driving method, and gate driver circuit driven by DC supply. The simulation results show that our proposals meet 8 K 120 Hz driving requirements. Also, we have fabricated a prototype panel and confirmed both high‐speed driving and low power consumption.  相似文献   

3.
An electromagnetic MEMS flapping-wing micro air vehicle at insect scale is presented. The detailed scheme, design, micro fabrication and experiment are given in this paper. Firstly, by commercial software ANSYS and MATLAB, electromagnetic analysis, modal analysis and kinetics analysis are proposed. Moreover, based on the result of theoretical analysis, appropriate structure, material and inherent frequency are selected. Then, a new LIGA-like process based on SU-8 photoresist technology is adopted to fabricate thorax, tergum and vein. Finally, a 3.5 cm wingspan, 144 mg weight prototype is integrated, and then we finish the flapping test for this prototype, which has a flapping resonance frequency range of 120–150 Hz. The test result demonstrates the feasibility solution in the development of FMAV based on MEMS, this work is a stepping-stone on the path toward flying robotic insects.  相似文献   

4.
5.
A novel surface acoustic wave (SAW)-based gyroscope with an 80 MHz central frequency was developed on a 128° YX LiNbO3 piezoelectric substrate. The developed sensor was composed of a SAW resonator, metallic dots, and two SAW delay lines. A SAW resonator was employed to generate a stable standing wave with a large amplitude, metallic dots were used to induce a Coriolis force and to form a secondary SAW, and two delay lines were formed to extract the Coriolis effect by comparing the resonance frequencies between these two delay lines. Coupling of modes (COM) modeling was conducted to determine the optimal device parameters prior to fabrication. According to the simulation results, the device was fabricated and then measured on a rate table. When the device was subjected to an angular rotation, resonant frequency differences between the two oscillators were observed because of the secondary wave, generated by the Coriolis force, perturbed the propagation of the SAW in the sense element. Depending on the angular velocity, the difference of the resonance frequency was linearly modulated. The obtained sensitivity was approximately 172 Hz deg?1 s?1 at an angular rate range of 0–500 deg/s. Device performances depending on different mass weights and temperatures were also characterized. Good thermal and shock stabilities were observed during the evaluation process.  相似文献   

6.
In this article, a compact wideband microstrip‐to‐microstrip (MS‐to‐MS) vertical transition designed with a slotline stepped‐impedance resonator (SIR) is first presented. Compared with the existing wideband transitions, this proposed transition centered at f0 can tremendously extend its upper stopband via two introduced transmission zeros around 3f0 and 5f0. With the designed equivalent circuit, the working principle is theoretically discussed. To realize the size compactness of this proposed wideband transition, the slotline SIR is replaced by two back‐to‐back connected slotline Y‐junctions. Finally, a prototype wideband transition is simulated and fabricated. A wideband filtering response with its upper stopband up to 6.06 GHz under attenuation better than 15 dB is experimentally achieved as expected in the simulation.  相似文献   

7.
A novel dual-mass resonant output micromechanical gyroscope is proposed which utilizes resonant sensing as the basis for Coriolis force detection instead of displacement sensing. It can overcome the shortcoming of single-mass resonant output micromechanical gyroscope and can reduce the common mode acceleration error by using a dual-mass topology structure and lever differential mechanism. The structure and operating principle of the device are introduced. Moreover, some important theoretical analyses of the gyroscope are provided in detail. The analytical results have shown that the resonant frequencies of vibrating mass and double-ended tuning fork resonators are 3.153 and 62.853 kHz. The device has a frequency sensitivity of 12.535 Hz/deg/s and a mechanical noise floor of $ 7.957\deg /{\text{h}}/\sqrt {{\text{Hz}}} A novel dual-mass resonant output micromechanical gyroscope is proposed which utilizes resonant sensing as the basis for Coriolis force detection instead of displacement sensing. It can overcome the shortcoming of single-mass resonant output micromechanical gyroscope and can reduce the common mode acceleration error by using a dual-mass topology structure and lever differential mechanism. The structure and operating principle of the device are introduced. Moreover, some important theoretical analyses of the gyroscope are provided in detail. The analytical results have shown that the resonant frequencies of vibrating mass and double-ended tuning fork resonators are 3.153 and 62.853 kHz. The device has a frequency sensitivity of 12.535 Hz/deg/s and a mechanical noise floor of 7.957deg/\texth/?{\textHz} 7.957\deg /{\text{h}}/\sqrt {{\text{Hz}}} in air. The finite element simulation results verify the accuracy of analytical algorithms. The common mode acceleration error of device can be reduced by 97.6%. The device is fabricated by SOG (Silicon on Glass) micro fabrication technology. Some important performances are measured by experimental method. The micromechanical gyroscope can be used to estimate the rotation rate by further implementing the signal processing electronics.  相似文献   

8.
给出了一种基于全数字控制的高压动力锂离子电池组的充电器设计。电路采用全桥移相结构实现了3kW输出功率。由DSP控制器完成了全桥移相电路驱动控制、保护、状态指示及CAN通讯功能。该充电器可实现电池预充、恒流充、恒压充及电池故障判断等功能,经样机使用证明该设计合理。  相似文献   

9.
为了实现单片集成三轴陀螺仪,提出了一种完全对称的四方陀螺结构。介绍了该陀螺的结构设计及工作原理,给出了动力学简化模型,并给出了其动力学方程的详细推导。运用Ansys软件对陀螺结构进行了静态分析和模态分析,仿真结果表明,陀螺在施加100 GHz载荷下所受最大应力为1.942 MPa,陀螺各模态的固有频率分别为57.345 kHz、57.382 kHz以及57.395 kHz,各模态间匹配性能较好。对陀螺结构的仿真研究的结果表明其抗过载及模态匹配满足陀螺的设计要求。  相似文献   

10.
针对数模混合电路仿真精度与性能之间的矛盾问题和仿真工业级复杂数模混合电路时仿真工具存在主流芯片和电路模块不足问题,提出了一种粘合模式的数模混合仿真平台模型架构,基于该架构设计并实现了一种基于Simulink软件,通过嵌入数字电路和模拟电路主流仿真引擎获得充足主流芯片和电路模块支持的数模混合电路仿真平台,设计了一种结合了拓扑排序算法的仿真控制方式,实现了对工业级复杂电路进行流程化、模块化的数模混合仿真;最后通过一个能够时序上可以逻辑拆分的典型数模混合电路仿真验证了仿真平台的有效性。  相似文献   

11.
Dispersed‐type inorganic electroluminescent (EL) devices composed of a transparent electrode, a phosphor, a dielectric, and a back electrode were prepared under various conditions using a zinc sulfide (ZnS)‐based phosphor. Additionally, a voltage/frequency variable circuit was designed. A compact high‐voltage/frequency variable circuit including three modules for boosting, frequency conversion, and voltage conversion was designed. A 140 Vpp voltage and a frequency in the range of 270 Hz to 2.4 kHz can be controlled by this circuit. The emission has begun to be observed at a voltage about 60 Vpp and a frequency of 400 Hz, at a voltage about 40 Vpp and a frequency of 1.4 kHz, 2.4 kHz, respectively. The emission intensity increased with an increase in frequency; emission with a wavelength of 450 nm was strongly influenced by the frequency. The luminescence and the electrical properties were affected by the preparation conditions including device structures, dispersion of ZnS:Cu, and Cl particles because of the current path generated by defects in the EL cell.  相似文献   

12.
The shaking table is an essential testing tool in the development of earthquake resistant buildings and infrastructure, so improving its performance is an important contribution to saving lives. Currently the bandwidth and accuracy of shaking tables is such that earthquake motion often cannot be replicated with the desired fidelity. A new model-based motion control method is presented for multi-axis shaking tables. The ability of this method to decouple the control axes is demonstrated. A linear parameter varying modal control approach is used – i.e. the modes of vibration of the system are controlled individually, with the modal decomposition repeated at each time step to account for parameter variations. For each mode, a partial non-linear dynamic inversion is performed in the control loop. Feedback is based on a combination of position and acceleration measurements. A command feedforward method is proposed to increase the tracking bandwidth, thus the controller has a two degree-of-freedom structure. Experimental and simulation results are presented for a large (43 t total) six degree-of-freedom shaking table. The simulation results are based on a detailed, validated model of the table. Experimental results show that the controller gives exceptional performance compared a conventional proportional controller: for example the horizontal acceleration bandwidth is six-times higher at over 100 Hz, which is also many times higher than the hydraulic resonant frequency. These results will allow a step change in earthquake simulation accuracy.  相似文献   

13.

A new fast readout circuit employing the known coding scheme of code division multiple access (CDMA) is successfully designed and applied to a 7-inch ultra-thin, flexible on-cell touch screen panel (TSP). The adopted CDMA is known originally as a coding scheme for data communication, which is applied in this study to address the sensing electrodes of the ultra-thin flexible touch panel. Due to the orthogonality between the driving signals to the touch panel coded by Walsh transform, one type of CDMA, the interference noises between sensing electrodes can be reduced effectively to render accurate touch sensing results. The electromagnetic interference from the flexible display can also be filtered out as baseline component in the output signal. And the frame time of touch reporting can be substantially shortened. Following the sensing electrode is a new readout designed of the switched-capacitor (SC) circuit, to avoid distributing sample signals from parasitic capacitance and also to enlarge the voltage changes due to the capacitance changes caused by touches. A 12-bit analog-to-digital converter (ADC) is orchestrated after the SC circuit to transform the front-end analog signal to digital codes. The digital part of the designed readout adopts a correction algorithm to eliminate the background signals from the display, and also a moving average algorithm to minimize the higher-frequency noises from the display and other electrodes. Experiments are conducted to validate the expected performance. It is evidenced that the Walsh code driving algorithm improves the quality of the readout output signal to be in 42 dB SNR, the report rate to a fast 240 Hz, and a power consumption of 0.39 mW by each sensing channel.

  相似文献   

14.
设计了一款PWM控制模式降压式(buck)直流一直流转换器芯片。该芯片为电压反馈控制模式,内部补偿使得反馈控制有很好的线性和很快的负载响应而无需通过外部设计。芯片采用CMSC0.5μm BCD工艺实现。PSPICE仿真结果表明,输出电压只有大约50mY的纹波,静态电流为3mA左右。输出电压在低于0.5V时,芯片具有短路降频功能,工作频率由81KHz降到23KHz左右,输出负载由0.2A跳变到2A时具有很好的负载调整率,大约为0.2%,转换效率可以达到85%以上。  相似文献   

15.
A novel single layer miniaturized frequency selective surface made of circular unit cell elements is presented in this article. The frequency selective surface (FSS) unit cell measures 0.055λ0 × 0.055λ0, where λ0 corresponds to its free space wavelength. The proposed FSS offers band stop characteristics with bandwidth of 137.5 MHz centered at 1.39 GHz. The symmetrical structure of the unit cell elements provides polarization independency. The miniaturized unit cell elements help achieving angular independency for both TE and TM mode of polarization. The miniaturized design provides excellent angular independency with negligible frequency shift for varying incident angles. A prototype of the FSS is fabricated and its simulation results are validated using measurements.  相似文献   

16.
In this article, a balanced‐to‐balanced (BTB) ultra‐wide band (UWB) power divider (PD) is proposed, which can realize arbitrary power‐dividing ratio (PDR) with improved transmission bandwidth flatness. The proposed PD is primarily based on microstrip/slotline (MS) transition structures and parallel‐coupled three‐slotline structure. U‐type microstrip feed lines integrated with stepped‐impedance slotline resonators are adopted at the input and output ports, which make the differential‐mode (DM) responses independent of the common‐mode (CM) ones. Meanwhile, superior DM transmission and CM suppression are achieved intrinsically, thereby simplifying the design procedure significantly. By changing the distances between the coupled three slotlines, the PDR between the output ports is controllable. In order to verify the feasibility of the proposed design method, several prototype circuits of the proposed PDs with different PDRs are simulated and a prototype circuit with the 2:1 PDR is fabricated and measured. A good agreement between the simulation and measurement results is observed.  相似文献   

17.
硅微陀螺敏感电容电荷读出电路性能的优劣直接决定着陀螺仪测量精度.通过对敏感电容读出电路的建模分析,采用差分调制技术实现了低噪声信号输出,从电路组成、参数设置、PCB布局布线等多方面综合考虑,优化设计了能抑制低频噪声以及高灵敏度电荷读出电路.实验结果表明:该电路输出噪声为-116.24 dBV/√Hz,敏感电容检测分辨率可达1.16 ×10-19 F√Hz.  相似文献   

18.
介绍了一种全新的硅微阵列陀螺仪的结构设计、模态仿真、电路闭环控制、数据融合方法和相关的的实验结果。基于热弹性阻尼理论的数值仿真,利用结构解耦的方法设计了硅微阵列陀螺仪的四质量块结构。利用ANSYS软件对硅微阵列陀螺仪的驱动模态和检测模态进行了仿真,仿真结果表明:硅微阵列陀螺仪共有四种不同的工作模态。根据静电力反馈原理,设计了基于数字锁相控制和数字闭环控制方法的控制电路。电路测试结构表明硅微阵列陀螺仪驱动模态的振动幅值的相对稳定性可以达到9×10-5。分析了硅微阵列陀螺仪的随机漂移特性,建立了漂移误差模型,并设计了卡尔曼滤波器以获取硅微阵列陀螺仪的随机漂移的最优估计。利用多传感器信息融合算法,硅微阵列陀螺仪的零偏稳定性可以提高10倍。  相似文献   

19.
Zhang  Zengping  Chang  Dan  Jia  Bin 《Microsystem Technologies》2019,25(6):2515-2524

The non-driven MEMS gyro is a new kind of micromechanical vibratory gyro, which has no a driving structure itself. The gyro is installed on a rotating aircraft and utilizes the spinning of the carrier to obtain an angular momentum. When the carrier produces a transverse rotation, a periodic Coriolis force acts on the sensitive mass of the MEMS gyro to sense the transverse input angular velocity of the rotating carrier. In applications, we found that the MEMS gyro is subjected to a high shock when the carrier begins to launch. If the sensitive mass cannot return to balance, the gyro will not work properly. So the stability of the gyro is the key issue on whether it can properly work. In this paper, we have analyzed the stability of the MEMS gyro in details by using Lyapunov stability principle for the first time. Firstly, based on the designed structural principle of the MEMS gyro, by using Euler dynamic equation of a rigid body rotating around a fixed point, we have described the angular vibration of the sensitive mass of the gyro and obtained its motion equation. The motion is the second order system. Then, we have chosen an appropriate state vector and established a state space model in state space for describing the motion of the sensitive mass. In order to research the stability of the designed MEMS gyro by using Lyapunov stability principle, a Lyapunov function needs to be found. Therefore, we have built a quadratic function and proved that its Lyapunov matrix equation has a solution. The matrix solution is symmetric and positive definite. Thus, the found quadratic function is a Lyapunov function. According to Lyapunov stability principle, the designed MEMS gyro is asymptotically stable. Next, utilizing numerical calculation, we have done the simulation of the unit-impulse response. The response curve has shown that the system of the designed MEMS gyro can come back to the balance after 160 ms. Finally, for further verification, the MEMS gyro is fixed on the shock table to test. The shock wave is a half-sine with the strength of 60 g and the impulse width of 80 ms. The tested result has demonstrated that the output signal of the designed MEMS gyro can again come back to zero state position after 150 ms under shock disturbance.

  相似文献   

20.
Limited travel stroke constrains the application of existing XYZ parallel micro/nano-positioning stages. In this paper, a novel parallel-kinematic symmetrical micro/nano-positioning stage is proposed to enlarge the travel range with a compact physical size. For a large-stroke parallel stage, the cross-axis motion increases the difficulty of closed-loop control process. The motions of the parallel stage on different axes are decoupled by employing I-shaped flexure hinges in this work. In order to obtain a large input displacement for actuating the stage, three voice coil motors (VCM) are adopted. In view of the lower output force of the VCM, the guiding flexure mechanism is designed with an optimized cross-sectional dimension. To verify the performance of the stage, analytical modeling and simulation study are carried out. A prototype stage is fabricated for experimental studies. Results show that the designed parallel micro/nano-positioning stage owns a three-degree-of-freedom motion workspace of 2.22 mm × 2.22 mm × 1.81 mm with an overall size of 176 mm × 176 mm × 198 mm, which is more compact than existing symmetrical designs containing the actuators. Moreover, the symmetrical design enables a low crosstalk of 1.7% among the three working axes.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号