A Novel Tilt and Acceleration Measurement System Based on Hall-Effect Sensors Using Neural Networks

A tilt sensor is a device used to measure the tilt on many axes of a reference point. Tilt sensors measure the bending position according to gravity and are used in many applications. Slope sensors allow easy detection of direction or slope in the air. These tilt gauges have become increasingly popular and are being adapted for a growing number of high-end applications. As an example of practical application, the tilt sensor provides valuable information about an aircraft’s vertical and horizontal tilt. This information also helps the pilot understand how to deal with obstacles during flight. In this paper, Hall-effect effective inclination and acceleration sensor design, which makes a real-time measurement, have been realized. 6 Hall-effect sensors with analog output (UGN-3503) have been used in the sensor structure. These sensors are placed in a machine, and the hall sensor outputs are continuously read according to the movement speed and direction of the sphere magnet placed in the assembly. Hall sensor outputs produce 0–5 Volt analog voltage according to the position of the magnet sphere to the sensor. It is clear that the sphere magnet moves according to the inclination of the mechanism when the mechanism is moved angularly, and the speed of movement from one point to the other changes according to the movement speed. Here, the sphere magnet moves between the hall sensors in the setup according to the ambient inclination and motion acceleration. Each sensor produces analog output values in the range of 0–5 V instantaneous according to the position of the spheroid. Generally defined, according to the sphere magnet position and movement speed, the data received from the hall sensors by the microcontroller have been sent to the computer or microcomputer unit as UART. In the next stage, the actual sensor has been removed. The angle and acceleration values have been continuously produced according to the mechanism’s movement and output as UART. Thanks to the fact that the magnet is not left idle and is fixed with springs, problems such as vibration noises and wrong movements and the magnet leaning to the very edge and being out of position even at a slight inclination are prevented. In addition, the Hall-effect sensor outputs are given to an artificial neural network (ANN), and the slope and acceleration information is estimated in the ANN by training with the data obtained from the real-time slope and accelerometer sensor.

Mango Leaf Monitoring with Inductive and Capacitive Sensors and Its Comparison with Trunk Dendrometer Measurements

Mango is one of the main fruits grown in Mexico that are exported worldwide, but the trees consume a lot of water, and irrigation scheduling should be implemented to optimize water use. Dendrometers were installed in fruit trees to optimize water usage during 2019 and 2020. A capacitor with Teflon clamps pressurized the leaf, and its dielectric changed with leaf water content. Additionally, Hall sensors were installed in leaves to study the effect of water during mango production. It was found that capacitance tend to be more sensitive than magnetic field monitoring. Higher changes were noted during midday with warm weather. Thresholds from the capacitance and Hall effect sensors can provide signals for irrigation scheduling.

Design and simulation of 5kW BLDC motor with half-buried permanent magnets using an existing stator body

<span lang="EN-US">This paper proposes a design of a 5 kW, 100 volts brushless direct current (DC) (BLDC) motor using an existing stator connected to an inverter and equipped with Hall sensors. The stator is a radial flux motor-type with 54 slots positioned at the outer side of the machine. In this case, the design is focused on the rotor components and winding configuration. However, the inverter aspects are also taken into account. At the same time, it considers the expected outputs: voltage, power, speed; and some limitations: maximum current and flux density. Finite element magnetic-based simulation is performed to extract the magnetic flux distribution, and analytical calculations are then conducted to obtain the output values and characteristics. The results show the BLDC motor at nominal speed produces 5.1 kW output power with 122.34 V voltages, 97.09% efficiency, and torque of 32.82 Nm. The maximum torque and rotation speeds are 51.39 Nm and 4,150 rpm respectively, while the peak-to-peak cogging force is 1.35 Nm. It can be concluded that the BLDC motor has a good performance and is compatible with the connected inverter.</span>

Battery Powered Lawn Mower

An electric lawn mower supplied from batteries was designed and constructed. Li-ion cells are used because of their high volumetric and weight energy density. Falling prices of these batteries allow such a conception to be practical. Two separate motors are used – one for the traction and the other for the main blade drive. Both motors are brushless DC motors (three-phase synchronous motors with permanent magnets with a specific waveform of the induced voltage). Hall sensors are used to sense the rotor position which is necessary for the control of converters. A high torque outrunner construction of the blade motor was selected to eliminate the need of a gearbox. The used battery capacity of 1.6 kWh was shown to be unnecessarily high for a practical operation – a long operation time (more than 3 hours for one charge), high weight.

DEPENDENCE OF MAXIMAL SENSITIVITY OF THE MAGNETIC FIELD HALL SENSORS BASED ON GRAPHENE ON TEMPERATURE

A theory of graphene-based magnetic field Hall sensors sensitivity dependence on temperature is summarized. The existence of low-temperature range with sensitivity, almost independent on temperature, is predicted; at higher temperatures, when thermally-induced carrier concentration in graphene prevails, the sensitivity decreases with temperature. The experimental studies of the temperature dependence of magnetic sensitivity of Hall sensors on single layer graphene base were carried in temperature range from 300 °K to 430 °K. The values of sensitivity, obtained for room temperatures ~ 230 V·А‑1·Т‑1 exceed essentially the maximum sensitivity of the traditional Hall sensors on silicon base ~ 100 V·А‑1·Т‑1.

Magnetic position sensors

Magnetic position sensors are popular in industrial and automotive applications since they are robust, resistant to dust and oil and they can be cheap. However, precise magnetic position sensors can achieve 0.015 % accuracy and 10 nm resolution. The maximum achievable range is about 20 m. DC magnetic position sensors are using a permanent magnet as a field source. As a field sensor, magnetoresistors are often used instead of traditional Hall sensors. Eddy current sensors work also with non-magnetic conduction targets. Magnetostrictive sensors are based on the time-of-flight of the elastic wave excited in the magnetostrictive material. The sensors can be several meters long and their applications range from level meters to hydraulics. Magnetic trackers and long-range position sensors utilize AC field sources, which are detectable from distances up to 20 m. Compared to optical instruments magnetic trackers do not need direct view. Their applications include surgery, mixed reality, and underground and underwater navigation.

Experimental Verification of the Magnetic Field Topography inside a small Hall Thruster

The magnetic circuit of a 500 W class Hall thruster, an electric propulsive device for spacecraft, was characterized experimentally and the results compared with simulation in order to verify the design. The commercial 3D gaussmeter, which was used in this work, was additionally recalibrated to compensate for translation and rotation of individual Hall sensors inside the probe. The Stokes stream function approach was applied to reconstruct the magnetic field topography in the thruster. The procedure, carried out on four different cases, yielded very good agreement between simulations and measurements, even for cusped configurations. Presented technique could be used as a robust method of verification of new magnetic circuit designs not only for Hall thrusters but also for a wide class of plasma devices for which detailed knowledge about actual distribution of magnetic field is crucial for optimization.

Structure and 3-D Model of a Solid State Thin-Film Magnetic Sensor

Vector 3-D magnetic sensors form the basis of measurement devices for magnetic field mapping and magnetic tracking. Typically, such sensors utilize specific constructions based on split Hall structures (SHS). An SHS-based 3-D magnetic sensor is a bulk semiconductor integrated structure with 8 or more contacts. Combining current flow directions through the contacts and measuring the corresponding voltages, one defines projections BX, BY, BZ of the magnetic field vector. This work presents a novel design of 3-D solid state magnetic sensors that requires no insulation by p-n junctions and can be implemented by thin-film technology traditionally used for fabrication of Hall sensors including those based on InSb films. Besides, a SPICE model of the 3-D magnetic sensor is provided, which helps design the proposed sensor and refine techniques of its calibration.

Study of a Modified Obstruction Free Pressure Sensor Based Flow Transducer Using Hall Sensors

In the present paper, a modified obstruction free pressure sensor-based flow transducer has been developed using Hall sensors. This technique is a modified version of the earlier inductive method. In this transducer, the fluid pressure in the pipeline is taken as the flow sensing parameter, and various drawbacks of the earlier inductive technique are eliminated. A prototype unit of the transducer is developed and studied in the present work. The transducer consists of two identical C-type Bourdon gauges, each fitted with an identical permanent magnet and Hall sensor assembly to sense the fluid pressure under flow condition and static pressure under no flow condition. The difference between the two Hall sensor outputs is found to vary nonlinearly with flow rate. The mathematical relations describing the working of the prototype unit are derived in the paper. The static characteristic curves of the proposed flow transducer are determined experimentally and reported in the paper. The characteristic curves are found to follow the derived equations to a very good extent with negligible percentage deviation from best-fit nonlinear characteristic.