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The purpose of this paper is to introduce a low-cost quadrotor that can be used for educational purposes and investigate the applicability of a low-cost MEMS laser sensor for accurate altitude control.

A single printed circuit board is designed to form the structure of the quadrotor. A low-cost MEMS motion sensor, a microcontroller and four small motors are mounted on the board. A separate laser sensor module measures the altitude. A remote controller is designed to control the quadrotor’s motion. The remote controller communicates with the quadrotor via wireless connection. Roll and pitch attitude stabilization is achieved using the proportional and derivative control algorithm. The applicability of an MEMS laser sensor for altitude control is also studied.

The low-cost quadrotor works well even though its body structure is made using a printed circuit board. Low pass and Kalman filters work well for attitude estimation and control application. The laser sensor is very accurate and good for altitude feedback; however, it has a relatively short measurement range and its sampling rate is relatively slow, which limits its applications. The vertical velocity obtained by differentiating the laser altitude has delay and inhibits suitable damping. Using the vertical velocity obtained by integrating the vertical accelerometer’s output, the damping performance is improved.

Developing a low-cost quadrotor that can be used for educational purposes and successfully implementing altitude control using a laser sensor and accelerometer.

Physical contact and traditional sensitive structure Physical contact and traditional pressure-sensitive structures typically do not operate well in harsh environments. This paper proposes a high-temperature pressure measurement system for wireless passive pressure sensors on the basis of inductively coupled LC resonant circuits.

This paper begins with a general introduction to the high-temperature pressure measurement system, which consists of a reader antenna inductively coupled to the sensor circuit, a readout unit and a heat insulation unit. The design and fabrication of the proposed measurement system are then described in detail.

A wireless passive pressure sensor without an air channel is fabricated using high-temperature co-fired ceramics (HTCC) technology and its signal is measured by the designed measurement system. The designed heat insulation unit keeps the reader antenna in a safe environment of 159.5°C when the passive sensor is located in a 900°C high-temperature zone continuously for 0.5 h. The proposed system can effectively detect the sensor’s resonance frequency variation in a high bandwidth from 1 to 100 MHz with a frequency resolution of 0.006 MHz, tested from room temperature to 500°C for 30 min.

Expensive and bulky equipment (impedance analyzers or network analyzers) restrict the use of the readout method outside the laboratory environment. This paper shows that a novel readout circuit can replace the laboratory equipment to demodulate the measured pressure by extracting the various sensors’ resonant frequency. The proposed measurement system realizes automatic and continuous pressure monitoring in a high-temperature environment with a coupled distance of 2.5 cm. The research finding is meaningful for the measurement of passive pressure sensors under a wide temperature range.

Si-based micro electro mechanical systems (MEMS) magnetometer does not require specialized magnetic materials avoiding magnetic hysteresis, ease in fabrication and low power consumption. It can be fabricated using the same processes used for gyroscope and accelerometer fabrication. The paper reports the dicing mechanism for the released MEMS xylophone magnetic sensor fabricated using wafer bonding technology and its characterization in ambient pressure and under vacuum conditions. The purpose of this paper is to dice the wafer bonded Si-magnetometer in a cost-effective way without the use of laser dicing and test it for Lorentz force transduction.

A xylophone bar MEMS magnetometer using Lorentz force transduction is developed. The fabricated MEMS-based xylophone bars in literature are approximately 500 µm. The present work shows the released structure (L = 592 µm) fabricated by anodic bonding technique using conducting Si as the structural layer and tested for Lorentz force transduction. The microstructures fabricated at the wafer level are released. Dicing these released structures using conventional diamond blade dicing may damage the structures and reduce the yield. To avoid the problem, positive photoresist S1813 was filled before dicing. The dicing of the wafer, filled with photoresist and later removal of photoresist post dicing, is proposed.

The devices realized are stiction free and straight. The dynamic measurements are done using laser Doppler vibrometer to verify the released structure and test its functionality for Lorentz force transduction. The magnetic field is applied using a permanent magnet and Helmholtz coil. Two sensors with quality factors 70 and 238 are tested with resonant frequency 112.38 kHz and 114.38 kHz, respectively. The sensor D2, with Q as 238, shows a mechanical sensitivity of 500 pm/Gauss and theoretical Brownian noise-limited resolution of 53 nT/vHz.

The methodology and the study will help develop Lorentz force–based MEMS magnetometers such that stiction-free structures are released using wet etch after the mechanical dicing.

The paper aims to provide a review of how innovations in laser, acoustics, radar, magnetic and other sensor technologies are aiding in making unmanned vehicles more autonomous.

In‐depth interviews are carried out with exhibitors of sensors at the AUVSI exhibition.

Innovations in infrared, laser, acoustics, magnetic and other sensor technologies are helping unmanned vehicles better meet the challenge of an ever‐increasing range of applications in military, law enforcement, and commercial applications as well as agriculture, fishing and rescue operations.

These sensor innovations will help make robot applications of all types more autonomous, easier to create and more cost effective in unmanned as well as manufacturing, logistics, medical and other applications.

The paper provides an insight into some of the latest in laser, radar, acoustic, magnetic, accelerometer, vision and gyro sensors and how they are helping address robotic applications that one might have seen if they had been on the exhibition floor at the Las Vegas unmanned vehicle show (AUVSI) in 2012.

This paper seeks to establish an analytical reference model in order to optimize the frequency response of MEMS cantilever structures using cutouts.

Presented in this work is a method to tune the frequency response of MEMS cantilevers by using single cutouts of various sizes. From an interpretation of the analytical results, mass and stiffness domains are defined as a function of the cutout position on the cantilever. In this regard, the elastic properties of the MEMS cantilever can be trimmed through mechanical tuning by a single cutout incorporated into the device geometry. The Rayleigh‐Ritz energy method is used for the modeling. Analytical results are compared with FEM and experimental results.

The eigenvalues are dependent on the position and size of the cutout. Hence, the frequency response of the cantilever can be tuned and optimized through this approach.

MEMS microsystems are sensitive to microfabrication limitations especially at the boundary support of suspended structures such as microcantilevers.

MEMS cantilevers are resistant to low level vibrations due to their low inertia and the elastic properties of the silicon material. For sensor applications these qualities are highly regarded and explored. This analysis will contribute to the performance optimization of atomic force microscope (AFM) probes and micromechanical resonators.

A method to tune, with cutouts, the frequency response of microcantilevers is proposed. The data can provide insight into the performance optimization of micromechanical resonators through mass reduction. For industrial applications requiring optimized responses the cutouts can be incorporated into microcantilevers through focused ion beam (FIB) machining or laser drilling, for example.

The purpose of this paper is to review recent developments in sensors for application in unmanned vehicles.

This study included in-depth interviews with exhibitors of sensors and sensor integrators at trade shows and contact with providers of such devices to the industry.

Sensor innovation has made giant leaps in producing much smaller and smarter sensors to address unmanned vehicle requirements.

Developers of unmanned vehicles of all types may be surprised at the sensor innovations and new applications to which sensors are being applied in this rapidly advancing field.

A review of some of the latest sensor innovations and applications that one might have seen if they had been on the exhibition floor at the recent trade shows, followed industrial publications or announcements from sensor developers.

This paper aims to provide details of MEMS (micro-electromechanical system) sensors produced from materials other than silicon.

Following a short introduction, this first considers reasons for using alternatives to silicon. It then discusses MEMS sensor products and research involving sapphire, quartz, silicon carbide and aluminium nitride. It then considers polymer and paper MEMS sensor developments and concludes with a brief discussion.

MEMS sensors based on the “hard” materials are well-suited to very-high-temperature- and precision-sensing applications. Some have been commercialised and there is a strong, on-going body of research. Polymer MEMS sensors are attracting great interest from the research community and have the potential to yield devices for both physical and molecular sensing that are inexpensive and simple to fabricate. The prospects for paper MEMS remain unclear but the technology may ultimately find uses in ultra-low-cost sensing of low-magnitude mechanical variables.

This provides a technical insight into the increasingly important role played by MEMS sensors fabricated from materials other than silicon.

To describe new technological approaches and improvements to existing methods of measuring position in automation, sports and general applications.

Starts with interesting applications of established sensor technology in motorsports and aircraft manufacture. Then examines some new position sensors based on novel technology.

Optical techniques including lasers and linear encoding enable high precision position sensing over long distances. Laser scanning systems have some advantages over vision systems for pick and place applications. Differential global positioning system (GPS) and carrier‐wave techniques are giving millimeter accuracy to GPSs.

Highlights the more exciting aspects of position sensing.

This paper aims to deal with the measurement of positioning accuracies of microscale components assembled to fabricate micro-optical benches (MOB).

The concept of MOB is presented to explain how to fabricate optical MEMS based on out-of-plane micro-assembly of microcomponents. This micro-assembly platform includes a laser sensor that enables to measure the position of the microcomponent after its assembly. The measurement set-up and procedure is displayed and applied on several micro-assembly sets.

The measurement system provides results with maximum deviation smaller than ±0.005°. Based on this measurement system and micro-assembly procedure displayed in the article, it is shown that it is possible to obtain a positioning accuracy up to 0.009°.

These results clearly show that micro-assembly is a possible way to fabricate complex, heterogeneous and 3D optical MEMS with very good optical performances.