Types Of Construction Machinery Research Articles

STAE‐YOLO: Intelligent detection algorithm for risk management of construction machinery intrusion on transmission lines based on visual perception

AbstractThe distribution of transmission lines is complex, influenced by terrain and topography, making their maintenance and management challenging. With the advancement of global mechanization, various types of construction machinery and large‐scale mechanical equipment are continually increasing. Accidental contact of construction machinery near transmission lines poses a serious threat to the stability of the power system. Traditional drones and inspection robots face difficulties in achieving real‐time monitoring of construction machinery and equipment around transmission lines, quickly identifying potential risks. Conventional image processing techniques and convolutional neural networks struggle with effective handling of small targets and densely packed detection tasks involving multiple targets. To address these challenges, this paper proposes an intelligent detection algorithm Swin Transformer attention efficient algorithm‐you only look once (YOLO) (STAE‐YOLO). It is based on the Swin Transformer global self‐attention mechanism, cross‐channel fusion attention mechanism, enhanced small object detection framework, and a focused and efficient regression loss function. The experimental results show that the STAE‐YOLO algorithm model improved by 6.3% in mean average precision, 3.7% in precision, and 3.1% in recall compared to the baseline model. Meanwhile, deploying the window multi‐head self‐attention global self‐attention mechanism in the model can strengthen the global multi‐scale semantic information in detection.

Transmission Line External Breakage Early Warning Method Based on Electric Field Perception

To prevent construction machinery from intruding into the transmission corridor during operation and causing damage to the normal operation of the line, this paper uses the relationship between the horizontal distance of the boom measurement point at the minimum safe distance, the angle of the boom to the ground and the field strength as a comprehensive criterion to carry out an early warning of the transmission line breaking. The method studied in this paper can provide a simple and accurate distance warning method for various types of construction machinery when they work in the vicinity of different types of transmission lines.

Monocular Vision–Enabled 3D Truck Reconstruction: A Novel Optimization Approach Based on Parametric Modeling and Graphics Rendering

Three-dimensional (3D) truck information, e.g., geometry, orientation, and position, can enable various smart construction applications such as monitoring earthwork, enhancing construction safety, and promoting productivity. Whereas stereo cameras have been explored extensively, the use of monocular vision (MV) for object 3D reconstruction still lacks substantial documentation. This study advances the field of MV-enabled 3D truck reconstruction by formulating it as an optimization problem. First, the general geometry of trucks was conceptualized and used to form a truck parametric model (TPM). Then the TPM was rendered by a computer graphics engine to generate synthetic views of the truck. Finally, an optimization algorithm is proposed to calibrate variables of the TPM progressively to maximize the alignment of the synthetic views with a target truck image. The proposed approach, called Mono-Truck, was evaluated by both lab tests and field experiments. The lab tests demonstrated an average error of 10.1%, 6.7 mm, and 0.7° in estimating the truck’s dimensions, position, and orientation, respectively. In the field experiments, Mono-Truck performed well compared with the baseline. This study contributes to the knowledge body by opening a new avenue to the monocular 3D truck reconstruction problem from an optimization perspective. The proposed approach can be generalized further to other types of construction machinery (e.g., excavators, cranes, and bulldozers) for their 3D reconstruction and smart applications.

Study on Emission Characteristics and Emission Reduction Effect for Construction Machinery under Actual Operating Conditions Using a Portable Emission Measurement System (Pems)

With the acceleration of urban construction, the pollutant emission of non-road mobile machinery such as construction machinery is becoming more and more prominent. In this paper, a portable emissions measurement system (PEMS) tested the emissions of eight different types of construction machinery under actual operating conditions and was used for idling, walking, and working under the different emission reduction techniques. The results showed that the pollutant emission of construction machinery is affected by the pollutant contribution of working conditions. According to different emission reduction techniques, the diesel oxidation catalyst (DOC) can reduce carbon monoxide (CO) by 41.6–94.8% and hydrocarbon (HC) by 92.7–95.1%, catalytic diesel particulate filter (CDPF) can reduce particulate matter (PM) by 87.1–99.5%, and selective catalytic reduction (SCR) using urea as a reducing agent can reduce nitrogen oxides (NOx) by 60.3% to 80.5%. Copper-based SCR is better than vanadium-based SCR in NOx reduction. In addition, the study found that when the enhanced 3DOC + CDPF emission reduction technique is used on forklifts, DOC has a “low-temperature saturation effect”, which will reduce the emission reduction effect of CO and THC. The use of Burner + DOC + CDPF emission reduction techniques and fuel injection heating process will increase CO’s emission factors by 3.2–3.5 and 4.4–6.7 times compared with the actual operating conditions.

Identification of steering wheel vibration source of internal combustion forklifts based on wavelet coherence analysis

The vibration of the internal combustion balance forklift and other types of construction machinery, especially the vibration at the steering wheel, has a significant impact on drivers’ work efficiency and comfort. Since most of the vibration sources of internal combustion forklifts during the working condition are nonstationary, how to accurately identify the nonstationary vibration sources that cause steering wheel vibration is of importance and challenging. This paper proposed an identification method for steering wheel vibration sources based on wavelet coherence analysis. Wavelet packet energy decomposition was used to determine the distribution of vibration energy at the steering wheel of an inter-combustion engine forklift truck for both idling and wide open throttle (WOT) conditions. Coherence analysis and source contribution analysis for the steering wheel vibration were carried out using FFT (coherence) and CWT (wavelet coherence) methods. The two methods and the results from the two conditions were compared and discussed. Results showed that wavelet coherence analysis can better identify the signal feature at low frequencies and provide global contribution analysis for the whole nonstationary conditions. In addition, it was found that the main vibration sources of the steering wheel vibration under the idling and WOT condition were different. A simple confirmation test was further conducted which proved the effectiveness of the proposed method.

Emission characteristics and chemical composition of particulate matter emitted by typical non-road construction machinery

According to the latest China Construction Machinery Industry Yearbook 2017, forklifts, loaders and excavators are three types of construction machinery that comprise the largest proportion of construction machinery in China. To study the emission characteristics of non-road mobile machinery, three types of non-road construction machinery used in the city were selected for testing and sampling. A Portable Emission Measurement System (PEMS) was used to obtain instantaneous exhaust emissions, and a portable particulate sampling system was used to collect PM2.5 samples from three types of construction machinery. The elements, water-soluble ions (WSIs), organic carbon (OC)/elemental carbon (EC) and polycyclic aromatic hydrocarbons (PAHs) were analysed. The China III standards for non-road construction machinery are stricter than the China II and China I construction machinery standards, indicating that strict regulations can help reduce PM emissions from non-road construction machinery. The results show that the fraction of the chemical components including elements, WSIs, OC/EC and PAHs to particulate matter is from 67.30% to 64.10%. The SO42−/NO3− ratio of each test vehicle is less than 1. The CE/AE values are all greater than 1, and the exhaust particles are alkaline. The estimated concentrations of secondary organic carbon (SOC) in the particulates discharged from loaders, excavators and forklifts are 3.73 mg/m3, 0.25 mg/m3 and 0.42 mg/m3, respectively, indicating the presence of secondary aerosols. The LMW-PAHs and MMW-PAHs were the major PAH species in the particulate matter, whereas a low concentration of HMW-PAHs is considered to be more harmful to human health than the other PAHs. All the PAH BaPeq values are higher than the BaP concentrations recommended by the World Health Organization. Compared with previous study, an increase in the emission standards for non-road mobile machinery can lead to a decline in pollutant emissions. In addition, the driving conditions, engine parameters, and the age of the vehicle and of non-road construction machinery, as well as the experimental methods used to study these variables, may affect the composition of exhaust emissions.

Review of hybrid electric systems for construction machinery

Abstract A large amount of construction machinery results in an enormous waste of energy and is a serious source of air pollution. Increasing fuel efficiency or using cleaner energy has become the most fundamental methods to solve this problem. First, this paper briefly introduces hybrid electric system (HES) structures. Second, HES for several types of construction machinery are comprehensively discussed and compared. Third, energy-saving control strategies for construction machinery are analysed in detail. Finally, the prospects and challenges of HES research for construction machinery are presented.

휠 로더 차축 테이퍼 롤러 베어링의 내구수명

휠 로더는 다양한 작업이 가능한 건설장비 중의 하나로서, 기능적 다양성과 구조적 신뢰성 향상의 요구가 증대되고 있다. 휠 베어링은 로더의 수명을 결정하는 핵심부품 중 하나이며, 테이퍼 롤러 베어링이 사용되고 있다. 일반적인 베어링 수명은 하중과 회전속도로 계산되고 있다. 테이퍼 롤러 베어링의 초기 예압은 내구수명에 직접적인 영향을 미치는 중요한 인자이다. 본 논문은 테이퍼 롤러 베어링에 작용하는 하중, 회전속도, 열 변형에 따른 초기 예압량을 포함한 내구수명 및 예압특성 관계를 제시하였다. 사용온도가 100 라면, 상온에 비해 과다 예압 상태가 되며, 내구수명은 약 20.3% 감소하는 결과를 나타내었다.

Dedicated Interactive Electronic Technical Manual for Construction Machinery Based on PDA and SQL Server CE Database

Modern construction machinery is usually advanced and intelligent with complicated structure and operating principle. Therefore its fault diagnosis and maintenance are very difficult. In order to promote the maintenance capability and supply detailed as well as easy-to-use technical information, we propose the method of developing Interactive Electronic Technique Manual (IETM) based on PDA. The framework of the technical manual and key implementation techniques are addressed. The technical manual is developed with Visual Studio .Net 2008, along with the XML-based data access method on PDA. The IETM system of a type of construction machinery is accomplished. The practical results show that it can overcome the inconveniences of paper manuals, and navigate users through extensive amounts of information quickly and easily. It greatly improves the maintenance and support capability of the Engineering Corps.

Operation Parameter Recorder for Construction Machinery Based on Embedded Technology

Conventional operation parameter monitoring device for construction machineries can only achieve sound (or light) alarm and control over over-limit status for operation parameters of construction machinery and it can not save any historical data, thus hinders accurate analysis, diagnosis and maintenance of the construction machinery. The operation parameter recorder for construction machinery developed based on industrial control computer and embedded technology can detect, record and manage the operation parameters. The real time fault alarm and historical data analysis can also be realized. The industrial computer, which is core module of this operation parameter recorder, controls the operation parameter acquisition module based on micro-controller ARMSTM32F103 to acquire and condition each operation parameter of the construction machinery. Application software running on the industrial computer processes the operation parameters and carries out alarm and control operations under abnormal conditions for fault protection. The abnormal data shall then be stored for later fault analysis. This operation parameter recorder can record many different types of operation data and has a large storage capacity, so it is applicable to many different types of construction machinery.

Vibration control of a telescopic handler using time delay control and commandless input shaping technique

A telescopic handler is a type of construction machinery used for the loading, transporting and unloading of various forms of cargo. To increase its productivity, the boom of the telescopic handler should be operated at high-speed mode without any occurrence of vibration. Residual vibration, however, in the boom often arises when lifting cargo to higher positions. To solve this problem associated with the occurrence of vibration, we applied time delay control and commandless input shaping technique, which is a modification-based on the concept of Input Shaping Technique. We confirmed their effectiveness through experiments.