Hedge Trimmer Research Articles

Sövényvágó kinematikai és rezgés vizsgálata

Hedge trimmers are handheld gardening power tools, used in households, where hedges or weaker vegetations are present. The aim of this paper is to investigate the mechanical behavior of a hedge trimmer that uses a circular eccentric disc firstly from a kinematic point of view, then from a vibration measurement point of view. During the vibration measurement, the FFT – Fast Fourier Transformation procedure is used to determine the source of vibration. This paper also aims to show how the different components affect the already mentioned vibration measurement results.

ANALYSIS OF THE EFFECTS OF WORKING POSITION ON MUSCLE FATIGUE DURING HEDGE PRUNING: A CROSS-SECTIONAL STUDY BASED ON CHINESE GARDEN WORKERS

Occupational health is still in the developmental stage in China. There is a lack of focus on garden workers. Hedge pruning is one of garden workers’ main tasks, a common operation form in modern landscaping. Garden workers who operate the hedge trimmer generally suffer from work-related musculoskeletal disorders (WMSDs). This study aims to demonstrate which working condition causes the most muscle fatigue, evaluate work fatigue accurately, and reduce WMSDs in garden workers. One hundred and twenty garden workers were studied during six hedge pruning conditions using surface electromyography (sEMG) and a motion capture system. The sEMG of the erector spinae, trapezius, biceps brachii and brachioradialis muscle, and kinematic parameters was measured during the operation. The average standardized sEMG values of upper-limb and trunk muscles in different working conditions were analyzed using single-factor analysis of variance. In the six working conditions, the trunk inclination angle was the largest (40–50∘) in horizontal pruning of short hedges, and the load of erector spinae (39.31–39.62%) was the highest in this condition. Operators’ arms were above shoulder height in high hedge pruning, the shoulder joint angle and the elbow joint angle were generally larger, the load of trapezius (49.33–55.65%), biceps brachii (46.50–52.35%) and right brachioradialis (52.35%) was the highest in horizontal pruning of high hedges, and the load of left brachioradialis (40.91%) was the highest in vertical pruning of high hedges. Awkward working postures can lead to problems such as overwork of upper-limb and trunk muscles, representing a risk that increases occupational illness, injuries and chronic diseases among garden workers. Preventive measures are required to reduce the occurrence of excessive local muscle load, and prevent the occurrence of occupational diseases.

Ergonomic Evaluation of Young Agricultural Operators Using Handle Equipment Through Electromyography and Vibrations Analysis Between the Fingers

BackgroundAgricultural handle equipment is present on all production areas' farms. They are handy and portable; however, excessive use can lead to acute traumas or accidental injuries. Repetitive movements, awkward postures, and hand-arm vibrations predispose them to pain and work-related musculoskeletal disorders. The purpose of this study was to observe the interaction of handle equipment in terms of electromyographic activity and analyze the postural work-related alterations. Materials and methodsTwenty male agricultural operators, mean age 24 ± 1.54 years, underwent the electromyographic analysis testing their muscular activities with a brushcutter, electric saw, and hedge trimmer in four different test conditions. ResultsThe brushcutter proved to be the agricultural handle equipment with the higher mean frequency (3.37 ± 0.38 Hz) and root mean square (5.25 ± 1.24 ms−2). Furthermore, the digital postural analysis showed a general asymmetry of the main arm and the respective side of the trunk. The head resulted right inclined in the anterior frontal plane by 5.7° ± 1.2°; the right scapula lower than the left in the posterior frontal plane (8.5° ± 1.8°), and a working trunk inclination of 34.15° ± 5.7°. ConclusionsVibrations of handle equipment and awkward working postures represent a risk for agricultural operators. Preventive measures are required to avoid young operators from experiencing musculoskeletal disorders all lifelong.

Design and evaluation of hedge trimmer robot

An autonomous hedge trimmer robot was developed to reduce the harmful effects of traditional hedge trimming method (gasoline-powered hedge trimmer) on operators' bodies and increase the speed and quality of the operation. The robot had five degrees of freedom (PRRRR) structure and was geometrically optimized to simplify the control strategy, enabling it to trim simple, stepped, and circular forms. The control system, consisting of a host computer, servo motors and servo drivers, and controller, guided the robot platform, manipulator, and end-effector as it approached and trimmed the hedge. By using a recognition algorithm and vision-based navigation system, the robot was able to detect the path and trim the hedge automatically. Experimental tests showed the vision-based system is accurate and fast enough to control the robot. The accuracy of hedge detection performance under various conditions was about 96% and the success rate of trimming was 88%.

Evaluation of panicle removal methods and crop topping applications as supplemental tools for wild oat (Avena fatua) management

AbstractIncreased frequency and occurrence of herbicide-resistant biotypes heightens the need for alternative wild oat management strategies. This study aimed to exploit the height differential between wild oat and crops by targeting wild oat between panicle emergence and seed shed timing. Two field studies were conducted either in Lacombe, AB, or Lacombe, AB and Saskatoon, SK, from 2015 to 2017. In the first study, we compared panicle removal methods: hand clipping, use of a hedge trimmer, and a selective herbicide crop topping application to a weedy check and an industry standard in-crop herbicide application in wheat. These treatments were tested early (at panicle emergence), late (at initiation of seed shed), or in combination at one location over 3 yr. In the second study, we investigated optimal timing of panicle removal via a hedge trimmer with weekly removals in comparison to a weedy check in wheat and lentil. This study was conducted at two locations, Lacombe, AB, and Saskatoon, SK, over 3 yr. Among all the tested methods, the early crop topping treatment consistently had the largest impact on wild oat density, dockage, seedbank, and subsequent year crop yield. The early (at panicle emergence) or combination of early and late (at initiation of seed shed) treatments tended to reduce wild oat populations the following season the most compared to the late treatments. Subsequent wild oat populations were not influenced by panicle removal timing, but only by crop and location interactions. Panicle removal timing did significantly affect wild oat dockage in the year of treatment, but no consistent optimal timing could be identified. However, the two studies together highlight additional questions to be investigated, as well as the opportunity to manage wild oat seedbank inputs at the panicle emergence stage of the wild oat lifecycle.

Design and analysis based on RecurDyn of the electric crawler type remote controlled hedge trimmer

The electric crawler type remote controlled hedge trimmer is designed to reduce the emission and change the present status that hedges on the both sides of the highway are trimmed manually, which wastes much time and increase the labor costs. The hedge trimmer is designed in this article according to the working conditions and objects; the author analyses its dynamic stability in the typical working environments by RecurDyn. And the research indicates that the electric crawler type remote controlled hedge trimmer has the reasonable design to perform a great dynamic stability.

Crude protein content in Urochloa cultivars (Syn. Brachiaria) in exclusive pasture system or consorciated with Macrotyloma axillare cv. Guatá

The objective of this study was to evaluate the crude protein content of Urochloa spp.cultivars (U. brizantha cv Marandu and U. decunbens cv. Basilisk), within a consortium systemwith Macrotyloma axillare cv Guatá. The experimental design was a completely randomized design,with four replications, in a factorial scheme (2 x 2), at which two types of grass (U. decumbensand U. brizantha) and two pasture types were studied (intercropped or exclusively fertilized with 60kg of nitrogen/ha) with repeated measures in time (samplings at two seasons of the year: February(summer) and August (winter)). Subsequently, samples were collected from a 2 m long PVC bar atfour points in each picket, and the forage cut close to the ground, with costal mowing coupled with0.5 m length hedge trimmer, each sample of 0.5 x 2.0 m, totalizing 1m2. The sampled material wasidentified, weighed and sent for analysis of crude protein to assess the contribution of leguminousin grass protein content. No significant differences were found when the type of grass versus type ofpasture interaction for the crude protein variable was met; however, significant differences were foundwhen evaluating the type of grass versus season interaction, at which the highest levels were foundwithin the month of February (summer), the same occurring for the interaction type of pasture versusseason of the year. It was concluded there were increases in crude protein content for U. decumbenscv. Basilisk and U. brizantha cv. Marandu when in consortium with M. axillare cv. Guatá in thesummer season.Keywords: Biological nitrogen. Forage. Forage quality. Leguminous.

Experimental Comparison of Vehicle Vibration Simulation Techniques

Abstract Performing accurate vehicle vibration simulation is imperative to understanding the adequacy of a packaged product's ability to withstand the rigors of transportation. Over the past decade, various vehicle vibration analysis techniques were proposed in order to provide better correlation to actual field shipments. This paper highlighted the observations made when an independent laboratory utilized four different methods in the simulation of vertical vibration and applied them to three different packaged products. A field data recorder was employed to record over-the-road vibration of a fully loaded steel spring truck traveling over interstates and highways. The collected data was analyzed independently using each of the different techniques and simulated in a lab with the necessary controller. This study is unique in that it considered the response of actual packaged products and through the use of a damage assessment tool, determined how well the techniques correlate with field vibration results. Additionally, two common industry vibration profiles were used to test the packaged products for comparison. The three packaged products used for these evaluations were a top-mount refrigerator, an electric hedge trimmer, and a gas-powered pressure washer. Results indicate that each of the proposed vehicle vibration analysis techniques produces product and package damage that correlates well with typical field vibration results for the three products tested. These results supported the further use of any of these techniques in the simulation of vehicle vibration.

The Economic Analysis of Semi-mechanised Harvesting of Lemon Balm

In recent years area for cultivation of Melissa officinalis is ranged around 40 ha. Low production could be also caused by less intensive use of machinery. Aerial parts could be fully harvested by mechanisation, but in case of small growers using of special machinery is not economic. The majority of growers harvest manually and this type of harvest represents up to 80% of the costs associated with the cultivation. The less expensive alternative of harvest by a hedge trimmer is evaluated in this article. The goal is to compare two ways of harvest (manual harvest and hedge trimmer harvest) of lemon balm aerial parts in production practise. According to results of experiments were calculated and determined boundaries of effective use of hedge trimmer in production of lemon balm in comparision to manual harvest and fully mechanised harvest. Obtained data shown an increase of harvest performance in case of hedge trimmer (0.0425–0.0525 ha.hr−1) compared to manual harvest (0.0185–0.0216 ha.hr−1). According to calculations, we can say that effective use of hedge trimmer (including purchase price) is from 0.37 ha at planting surface and 0.48 ha at planting rows. Results could also be used for other MAP crops with similar harvest technology as for lemon balm (for example Mentha spp., Origanum spp., Achillea spp.).

Numerical Simulating and Analysis of Highly Nonlinear Penetration Problem in Hedge Trimmer

The process of circular saw blades sawing hedge branches belong to typical highly nonlinear penetration problems, so it is difficult to measure the actual cutting force, and it will have different characteristics with the variational saw feeding speed. The result of display dynamic analysis in the ANSYS/LS-DYNA module to circular saw blades sawing branches can be very close to the actual results. This paper make the numerical simulation for the regular pattern of cutting force with the variational saw feeding speed, analysis the force of circular with the saw feeding speed, and get some variation of circular saw blades sawing process by force, which laid foundation for the future study.

Spatial variability of the noise level of a hedge trimmer and backpack blower

Despite the advantages associated to mechanization, the noise generated by machines and equipment may cause discomfort to workers, possibly even jeopardizing their health. Thus, this paper is aimed at assessing the noise level of two agricultural machines (hedge trimmer and backpack blower) and to characterize them spatially by means of geostatistics. Data collection was performed at the average height of the worker’s ear and within an equidistant circumference of 1 m up to the limit of a sample area with a radius of 22 m. The data fitted models of gaussian and spherical semivariograms for the evaluated equipment, a hedge trimmer and backpack blower, respectively. The spatial noise analysis allows for the definition of a work regime and the need for the use of personal protection equipment.

English

Performing accurate vehicle vibration simulations is imperative to understanding the adequacy of a packaged product’s ability to withstand the rigors of transportation. Over the past several years, various vehicle vibration analysis techniques have been proposed in order to provide better correlation to actual field shipments. Some of these new techniques allow for the vibration data collected to be analyzed in a manner that reduces the duration of the laboratory vibration simulation. This paper discusses the discoveries made when an independent laboratory utilized these techniques to reduce test durations for vertical vibration simulation. A field data recorder was employed to collect and record over-the-road vibration of a fully loaded steel spring truck traveling over interstates and highways. The collected data was analyzed independently for each of the different simulation techniques and the resulting simulations were conducted using a servo-hydraulic vibration table. This paper is unique in it evaluates the simulation techniques using actual packaged products, and by use of a damage assessment tool, determines how well the techniques correlated with actual field study results. The three packaged products used for these evaluations were as follows: top-mount refrigerator, electric hedge trimmer, and gas powered pressure washer. Results indicate it is possible to reduce the vibration test durations during vertical vibration simulation, while still correlating with results collected from field studies.

The Analysis and Research of Hedge Trimmer Robotics about Manipulator Kinematics

According to the analysis theory of the four freedom degree about the robots mechanical arm, in this paper established the four freedom degree of the mechanical arm forward and inverse kinematics equation, which was based on the coordinate system, giving the relationship of the spatial location and gesture between movement member and end executor. Besides, it could solve its Jacobian matrix, and provide theoretical basis to achieve the velocity control program on the end of mechanical arm in Cartesian space. The application of ADAMS had carried out the simulation, analysed the location and movement relations among the mechanical structure, which provided significant data for the actual hedge trimming operation.

Research & Design of the Multifunctional Landscape Hedge Trimmer

This paper presents a multifunctional landscape hedge trimmer. It has 6 degrees of freedom, and it can trim the shape of flat, cylinder, cone, sphere, etc. The controller takes the embedded LINUX ARM9 processor as the core. It has a high-speed real-time online interpolation function, and an error compensation function. With the help of the developed control software it can control the trimming process automatically, making the trimming speed faster and the precision higher, and with its single-person operation feature, it greatly reduces the labor intensity and improves the labor efficiency.

Cutting Performance Improvement of Hedge Trimmer

Cutting Performance Improvement of Hedge Trimmer

Early Precommercial Thinning of Redwood Sprout Clumps: Evaluation of Four Techniques

Redwood (Sequoia sempervirens (D. Don) Endl.) responds favorably to sprout clump thinning in clearcut environments, but appropriate silvicultural techniques for this practice have not been developed. Four power tools for this unique application were evaluated: standard mid-sized chainsaw (long saw), small arborist chainsaw (short saw), power hedge trimmer, and a customized power brushcutter. Linear mixed effects model analysis was conducted to determine tool differences in clump processing speed, transit time, cycle time, and worker difficulty (peak heart rate). Machine costs and unit production costs were calculated separately for each tool, and perceived ease-of-use by workers was noted. Clump difficulty (sprout clump size) was a strong determinant of processing time and affected the performance of each tool differently. The long saw performed well across the range of clump difficulties but forced the highest heart rates in operators and was the most costly. The short saw was especially proficient on easy to moderate clumps, was among the least difficult, and was the least costly; it was the clear favorite for easy clumps. The hedge trimmer was among the fastest and least difficult, but its capability was constrained by sprout caliper. The brushcutter’s lackluster performance and several inadequacies prevent its recommendation. Regardless of tool selection, the condition of the sprout clump is a factor that must be taken into consideration since it strongly affects average production rates (clumps processed per productive machine hour) and area costs. Sprout age and clump size should guide tool selection, but should also be considered by operators in selectively choosing a subset of crop stumps for sprout clump thinning.

Cordless Hedge Trimmer for Seed Collection

Cordless Hedge Trimmer for Seed Collection

Cordless Hedge Trimmer for Seed Collection

We use a rechargeable hedge trimmer to collect seeds of native plants. With an easy modification and an inverter that plugs into a vehicle cigarette lighter, the trimmer is ready to harvest seeds as we travel about.

Harvesting Native Seeds with a Gas Hedge Trimmer

Harvesting Native Seeds with a Gas Hedge Trimmer

Investigation of lawn-maintenance equipment noise

As the lawn-maintenance industry grows in suburban residential areas, it has become a new and significant source of environmental noise and occupational noise exposure. Due to the short duration at any one location and public acceptance of this activity, there are few community complaints about the noise (except at unreasonable hours). This paper will concentrate on recreational and occupational exposure, where individuals are exposed to high noise levels for long periods of time. Most lawn-maintenance workers spend from 8–10 h per day exposed to A-weighted sound levels greater than 85 dB, and it appears that few employees wear hearing protection. Sound levels were measured and monitored at the operator’s ear and measured at a distance of 10 ft for the following equipment: lawn mowers, gas and electric edgers, gas and electric trimmers, electric blowers, and an electric hedge trimmer. A-weighted sound levels at the operator’s ear ranged from 82 to 102 dB. A comparison of equipment sound levels will be presented as well as a comparison of noise levels for gas versus electric lawn equipment. Finally, daily noise exposure for lawn-maintenance employees will be developed using the data.