Abstract The human voice stands out for its rich information transmission capabilities. However, communication is susceptible to interference from noisy environments and obstacles. Here, we propose a wearable wireless flexible skin-attached acoustic sensor (SAAS) capable of capturing the vibrations vocal organs skin movements, thereby enabling recognition human-machine interaction (HMI) in harsh environments. This system utilizes piezoelectric micromachined ultrasonic transducers (PMUT),...

Here, we report a differential ring array of piezoelectric micromachined ultrasonic transducers (pMUTs) for ultralong-range detection. Among them, the structure is used to improve sensitivity device, and generated sound intensity. The synergy between improves acoustic performance pMUTs. material adopts aluminum nitride (AlN) thin film compatible with complementary metal–oxide–semiconductor (CMOS) process. resonant frequency device (80 kHz), radius ( <inline-formula...

Ultrasonic flowmeter is one of the most widely used devices in flow measurement. Traditional bulk piezoelectric ceramic transducers restrict their application to small pipe diameters. In this paper, we propose an ultrasonic gas based on a PZT micromachined transducer (PMUT) array. Two PMUT arrays with resonant frequency 125 kHz are as sensitive elements realize alternate transmission and reception signals. The sensor contains 5 × circular size 3.7 mm2. An FPGA resolution ns process received...

The canopy volume of fruit trees is an important input for the precise and varying application pesticides in orchards. fixed mesh division method mostly used to calculate volumes with variable target-oriented spraying. To reduce influence working speed on detection accuracy under a width division, cuboid accumulation divided areas (CADAs), which light ranging (LiDAR) online tree based dynamic proposed this paper. In method, area according number unilateral nozzles sprayer height direction...

Orchard spraying can effectively control pests and diseases. Over-spraying commonly results in excessive pesticide residues on agricultural products environmental pollution. To avoid these problems, variable technology uses target canopy detection to evaluate the leaf area a adjust application rate accordingly. In this study, mobile LiDAR platform was set up automatically measure point cloud data for thick an apple orchard. A test built, manual measurements of were taken. Then, polynomial...

Orchard pesticide off-target deposition and drift cause substantial soil water pollution, other environmental pollution. target-oriented spraying technologies have been used to reduce the caused by control pollution within an acceptable range. Two systems based on photoelectric sensors or ultrasonic were developed. Three treatments of young cherry trees adult apple conducted using a commercial sprayer with photoelectric-based system, ultrasonic-based system no system. A rhodamine tracer was...

Repeated and missed spraying are common problems during the working of boom sprayers, especially in breakpoint continuous process. Therefore, present study investigated a system for automatic-guidance sprayers based on hysteresis compensation algorithm spraying. An operational identification algorithm, which combines real-time kinematic global navigation satellite (RTK-GNSS) wheel odometer, was proposed; pre-adjusted proportional-integral-derivative (PID) control opening degree proportional...

To ensure boom sprayer safety and spraying efficiency, the height must be adjusted during pesticide application. The field variation characteristics of are basis balance adjustment. A detection system based on ultrasonic sensors was designed. Field tests were performed in 2.0 ha vacant fields 13.44 wheat stubble fields. signal processing method K-means clustering algorithm used to preprocess sensor data. results showed that could effectively improve accuracy an sensor. greatest at sides...

Low accuracy planting uniformity affects yield. Seed meter type and forward speed typically interfere with the of motor-driven seeding systems. Two types maize precision planters equipped systems are investigated in this study to ascertain rule both simulated field speeds. The increases from 5 12 km/h at a 1 interval laboratory environment. test results show that quality feed index (QTFI) two decreased by 16.79% 9.88%. This is primarily attributed increase miss (MISS) 11.62% 9.70%,...

Sprayer boom height (Hb) variations affect the deposition and distribution of droplets. An Hb control system is used to adjust maintain an optimum distance between crop canopy, detection sensor a key component system. This study presents new, low-cost light ranging (LiDAR) for developed based on principle single-point ranging. To examine performance LiDAR sensor, step experiment, field ground wheat stubble (WS) experiment as well comparison with ultrasonic were performed. The results showed...

In order to explore the influencing factors and laws of ultrasonic sensor detecting wheat canopy height, designed an detection height test platform with speed adjustable function. Taking step surface, bare soil as research objects, a calculation method based on K-mean clustering is proposed, response characteristics three media under different operating speeds are explored. Firstly, results show that average error 1.35%. When distance switched at step, increase distance, actual offset...

Different fruit tree canopies have different requirements for air speed and volume. Due to the strong relationship between volume, decoupled control of volume cannot be achieved using existing sprayers. In this study, an innovative air-assisted sprayer that supports independent adjustment fan (0-2940 r/min) outlet area (1022.05-2248.51 cm 2 ) is developed, maximum are 45.98 m/s 37239.94 m 3 /h, respectively. An test was carried out. The results indicated opposing effects on volume; can thus...

The orchard air-assisted sprayer exhibits strong droplet penetration, allowing uniform adhesion on both the front and back surfaces of leaves. spray deposition drift are influenced not only by amount pesticide but also airflow provided system. To meet requirements for regulating application in orchards, a method based iris structure continuous adjustment air inlet area was proposed. An control mechanism sprayers, which is easy to install, developed, circular recirculating pressure-stabilized...

The deposited pesticide distribution in fruit tree canopies is crucial for evaluating the efficacy of air-assisted spraying orchards. Most studies have determined impact application on deposition without a quantitative computational model. In this study, an orchard sprayer with airflow control was used to perform experiments artificial and peach trees. experiment tree, canopy leaf areas ranging from 2.54~5.08 m2 found require effective air speed 18.12~37.05 m/s. area, at fan outlet spray...

<b><sc>Abstract.</sc></b> Pesticide application rate and airflow supply are the two manipulated outputs of an orchard sprayer control system. The distribution pesticide deposits inside outside canopy fruit trees depends largely on supply. should be simultaneously controlled precisely to realize precision spraying. Based axial flow fan, this paper designs adjustment test bench that can independently fan speed, air inlet area angle deflector in bellows. speed is adjusted by DC motor. adopts a...

During variable-rate spraying in orchards, the atomization characteristics and distribution of droplets out target area can be affected by sprayer pressure. In this study, a control system test bench was designed, hollow cone nozzle QY82.317.22 selected. The droplet characteristics, including volume median diameter (Dv0.5), relative span spectrum, velocity at different spray pressures, were studied distances ranging from 0.4 to 2.4 m orifice with an air 10 m/s position. effects longitudinal...