Determination of forest road surface roughness by kinect depth imaging

Roughness is a dynamic property of the gravel road surface that affects safety, ride comfort as well as vehicle tyre life and maintenance costs. A rapid survey of gravel road condition is fundamental for an effective maintenance planning and definition of the intervention priorities. Different non-contact techniques such as laser scanning, ultrasonic sensors and photogrammetry have recently been proposed to reconstruct three-dimensional topography of road surface and allow extraction of roughness metrics. The application of Microsoft Kinect\u2122 depth camera is proposed and discussed here for collection of 3D data sets from gravel roads, to be implemented in order to allow quantification of surface roughness. The objectives are to: i) verify the applicability of the Kinect sensor for characterization of different forest roads, ii) identify the appropriateness and potential of different roughness parameters and iii) analyse the correlation with vibrations recoded by 3-axis accelerometers installed on different vehicles. The test took advantage of the implementation of the Kinect depth camera for surface roughness determination of 4 different forest gravel roads and one well-maintained asphalt road as reference. Different vehicles (mountain bike, off-road motorcycle, ATV vehicle, 4WD car and compact crossover) were included in the experiment in order to verify the vibration intensity when travelling on different road surface conditions. Correlations between the extracted roughness parameters and vibration levels of the tested vehicles were then verified. Coefficients of determination of between 0.76 and 0.97 were detected between average surface roughness and standard deviation of relative accelerations, with higher values in the case of lighter vehicles

Modelling noise propagation generated by forest operations: a case study in Southern Italy

Noise is defined as an undesired sound that constitutes an unwarranted disturbance potentiality modifying animal behaviour or normal functioning. Forest operations commonly involve the use of equipment and machines that can produce noise and be a potential permanent or temporary disturbance for the wildlife. This study simulates noise propagation in a natural area generated during coppice stand harvesting by direct field noise measurements and the application of a specific GIS model. Two working phases were investigated: felling and yarding operations. Two potential systems were analyzed for the yarding operations: a) yarding by mobile cable yarder and b) skidding by tractor with a three point log grapple. The results are reported in terms of excess noise area for the third-octave bandwidths with the centre in 500 Hz, 1000 Hz and 2000 Hz. Felling by chainsaws presented the largest area where noise exceeds the ambient natural noise, while in the case of yarding, mobile cable yarding operations presented a smaller area of excess noise than skidding by tractor

Tensile force monitoring on large winch-assist forwarders operating in British Columbia

The forest industry around the world is facing common challenges in accessing wood fiber on steep terrain. Fully mechanized harvesting systems based on specialized machines, such as winch-assist forwarders, have been specifically developed for improving the harvesting perfor- mances in steep grounds. While the mechanization process is recognized as a safety benefit, the use of cables for supporting the machine traction needs a proper investigation. Only a few studies have analyzed the cable tensile forces of winch-assist forwarders during real operations, and none of them focused on large machines normally used in North America. Consequently, a preliminary study focused on tensile force analysis of large winch-assist forwarders was conducted in three sites in the interior of British Columbia during the fall of 2017. The results report that in 86% of the cycles, the maximum working load of the cable was less than one-third of the minimum breaking load. The tensile force analysis showed an expected pattern of minimum tensile forces while the forwarders were traveling or unloading on the road site and high tensile forces when operating on steep trails, loading or traveling. Further analysis found that the maximum cycle tensile forces occurred most frequently when the machines were moving uphill, independently of whether they were empty or loaded. While the forwarders were operating on the trails, slope, travel direction, and distance of the machines from the anchor resulted statistically significant and able to account for 49% of tensile force variability. However, in the same conditions, the operator settings accounted for 77% of the tensile force variability, suggesting the human factor as the main variable in cable tensile force behavior during winch-assist operations

Evaluation of different wood harvesting systems in typical Mediterranean small-scale forests: a Southern Italian case study

Use of small-scale harvesting equipment in forestry is increasing in many regions of the world and tractor-based systemsare the most common type of small-scale forestry equipment. This equipment is smaller, less expensive and less productivethan advanced forestry machines and the choice of method depends on forest site-specific conditions. In southern Italy the prevailingconditions are those characteristic of small-scale forestry: harvested areas and volume are limited and ground-based extraction isstill the most common harvesting technique. Two harvesting systems conventionally adopted in Italian small-scale forestry are thoseusing either winch or grapple fitted farm tractors for wood extraction. A continuous time study was adopted to determine productivityrates and wood extraction costs and develop skidding time prediction models for these two different wood harvesting systems asused in typical Mediterranean forests, in chestnut and silver fir thinning operations. Comparing winch and grapple extraction revealedconsiderable differences in productivity (2.91 and 5.92 m3 h-1 respectively). Factors significantly affecting productivity differenceswere extraction distance and payload per turn. The study concluded that farm tractors can be used for small scale harvesting operationsand its results can be used to set piece rates, design and rationalize work and estimate costs. In order to sustain small-scaleharvesting equipment effectiveness, skid trails should be planned in forests. The use of farm tractors needs to be encouraged as analternative self-sufficient productivity method in small-scale forestry operations

Mechanical grading in PGI Tropea red onion post harvest operations

The growing interest expressed by consumers toward food products quality as well as toward their linkage to the territory, has led producers to fit to the continuous rising demand for “typical products”, and to look for new and more efficient production and marketing strategies. An emblematic case is represented by Tropea red onion that, as a typical product, plays an important role in economical and rural development of the territory to which it is linked. The organoleptic features offered by “Tropea Red Onion”, PGI certified (Calabria), have to be associated as well to the quality of services that accompanies its processing. Technology application in post-harvest operations, has certainly contributed to make faster and less tiring all processing tasks. The main problem related to the mechanization of Tropea red onion post-harvest operations lies in the removal of the various layers of the external tunic, making it impossible for optical or electronic grader to achieve this task in a satisfactory way since the sensors are not able yet to separate the “bulb” from its involucre. In this context, the current study aims to assess the productivity of three different machines used for round Tropea red onion grading, and determine their work efficiency. The carried out analysis highlighted the ability of the studied machines to ensure a high work capacity, while maintaining a high level of precision during calibration process. Such precision allows to decrease laborer employment and increase processing chain speed, rising as well the annual use of the machines, allowing consequently processing cost savings. For a more profitable employment of such graders, it is, however, necessary from one hand, to properly form the technicians responsible of processing plants management, and from the other hand, to be able to take advantage of a technical assistance network, able to serve users in a short time

A Three-Step Neural Network Artificial Intelligence Modeling Approach for Time, Productivity and Costs Prediction: A Case Study in Italian Forestry

The improvement of harvesting methodologies plays an important role in the optimization of wood production in a context of sustainable forest management. Different harvesting methods can be applied according to forest site-specific condition and the appropriate mechanization level depends on a number of factors. Therefore, efficiency and functionality of wood harvesting operations depend on several factors. The aim of this study is to analyze how the different harvesting processes affect operational costs and labor productivity in typical small-scale Italian harvesting companies. A multiple linear regression model (MLR) and artificial neural network (ANN) have been carried out to predict gross time, productivity and costs estimation in a series of qualitative and quantitative variables. The results have created a correct statistical model able to accurately estimate the technical parameters (work time and productivity) and economic parameters (costs per unit of product and per hectare) useful to the forestry entrepreneur to predict the results of the work in advance, considering only the values detectable of some characteristic elements of the worksite

Tensile Force Monitoring on Large Winch-Assist Forwarders Operating in British Columbia

The forest industry around the world is facing common challenges in accessing wood fiber on steep terrain. Fully mechanized harvesting systems based on specialized machines, such as winch-assist forwarders, have been specifically developed for improving the harvesting performances in steep grounds. While the mechanization process is recognized as a safety benefit, the use of cables for supporting the machine traction needs a proper investigation. Only a few studies have analyzed the cable tensile forces of winch-assist forwarders during real operations, and none of them focused on large machines normally used in North America. Consequently, a preliminary study focused on tensile force analysis of large winch-assist forwarders was conducted in three sites in the interior of British Columbia during the fall of 2017. The results report that in 86% of the cycles, the maximum working load of the cable was less than one-third of the minimum breaking load. The tensile force analysis showed an expected pattern of minimum tensile forces while the forwarders were traveling or unloading on the road site and high tensile forces when operating on steep trails, loading or traveling. Further analysis found that the maximum cycle tensile forces occurred most frequently when the machines were moving uphill, independently of whether they were empty or loaded. While the forwarders were operating on the trails, slope, travel direction, and distance of the machines from the anchor resulted statistically significant and able to account for 49% of tensile force variability. However, in the same conditions, the operator settings accounted for 77% of the tensile force variability, suggesting the human factor as the main variable in cable tensile force behavior during winch-assist operations

THE MEASUREMENT AND DISTRIBUTION OF WOOD DUST

In Italy, the woodworking industry presents many issues in terms of occupational health and safety. This study on exposure to wood dust could contribute to the realization of a prevention model in order to limit exposure to carcinogenic agents to the worker. The sampling methodology illustrated the analysis of dust emissions from the woodworking machinery in operation throughout the various processing cycles. The quantitative and qualitative assessment of exposure was performed using two different methodologies. The levels of wood dust were determined according to EN indications and sampling was conducted using IOM and Cyclon personal samplers. The qualitative research of wood dust was performed using an advanced laser air particle counter. This allowed the number of particles present to be counted in real time. The results obtained allowed for an accurate assessment of the quality of the dust emitted inside the workplace during the various processing phases. The study highlighted the distribution of air particles within the different size classes, the exact number of both thin and ultra-thin dusts, and confirmed the high concentration of thin dust particles which can be very harmful to humans

Forest-wood supply chain in Calabria (Italy).

Il lavoro fornisce un importante panorama sulla filiera foresta-legno in Calabria. In particolare, la ricerca analizza i recenti dati dell'inventario forestale e mette a confronto diversi studi condotti in Calabria sulla meccanizzazione forestale e sui processi di lavorazione del legno. Dopo aver descritto superfici, potenzialita produttive e condizioni di servizio del patrimonio forestale, sono stati esaminati i principali sistemi di lavoro adottati nelle tipiche utilizzazioni in Calabria mettendo in evidenzia importanti aspetti nell'ambito delle produzioni legnose a fini energetici. Infatti, in Calabria in pochi anni si e avuto un crescente aumento di macchine e attrezzature specifiche per il settore energetico con conseguente miglioramento in alcune realta del livello di meccanizzazione. Nella stessa regione sono in funzione ben cinque centrali elettriche alimentate a biomasse ed altri impianti per la produzione di energia elettrica sono in costruzione. Le attuali centrali hanno un consumo annuo di circa un milione di tonnellate di cippato di origine agro-forestale e stanno condizionando tantissimo la filiera legno-energia. Questo nuovo sbocco economico, insieme alla multifunzionalita del sistema bosco, puo favorire lo sviluppo di nuovi posti occupazionali attraverso una adeguata e minuziosa pianificazione forestale per salvaguardare e sviluppare l'intero territorio calabrese

Performance of a mid-sized harvester-forwarder system in integrated harvesting of sawmill, pulpwood and firewood

Fully mechanized timber harvesting systems are generally characterized by a high operational performance being widespread and used across many regions. Such systems are adaptable to different levels of operational integration, enabling also the recovery of energy wood, but given integration configurations affect their performance. A production study was carried out in a Norway spruce clear-cut aiming to investigate the performance of a mid-sized harvester-forwarder system in general, and the effect that fuelwood recovery from tree tops may have on its performance. Data was collected in the field during 11 days of observation using state-of-art equipment and software. Harvester’s operations were monitored using a digital camera. Data refined from 27.5 filmed hours that accounted for 1045 felled and fully processed trees was used to model and compute its performance indicators. In addition, fuel consumption data was sampled in the field. The results indicated that a delay-free cycle time consumption was affected by variables characterizing the tree size. The net production rate was estimated to about 26.5 m3 ∙ h-1, being substantially affected by supplementary tree-top processing. Forwarding operations were monitored using a handheld computer and a Global Positioning System unit. The delay-free cycle time consumption was affected by forwarding distance and the amount of loaded wood, resulting in a net production rate of about 19.2 m3 ∙ h-1. Under these circumstances, the forwarding performance matched the harvester’s outputs for an extraction distance of about 100 m, indicating that the supplementary processing of the tree-tops had no effect on the system’s productive performance in the studied conditions. Most likely, it affected the harvester’s fuel consumption given its proportion of 9% in the delay-free harvester’s cycle time. The results also indicated a mean fuel consumption of about 1.7 l ∙ m-3 for the studied harvesting system