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

Whole tree system evaluation of thinning a pine plantation in southern Italy

In Italy, some silvicultural treatment as thinning could be carried out in an economic way adopting systems based on small-scale mechanization. This paper examines the productivity standards of wood biomass in coniferous plantation thinning in Southern Italy under the conditions of small-scale forestry. The objectives of the study were to evaluate the incidence of different silvicultural treatments on productivity and harvesting costs and create productivity models for typical harvesting system used for wood thinned from Calabrian pine. Three different sites were monitored on the Sila Massif forest, and the experimental plan included three area tests, subjected in the last thirty years to intermediate cuttings with different thinning grade: light thinning (A thesis), moderate thinning (B thesis), heavy thinning (C thesis). The authors developed a productivity model for motor-manual felling and skidding timber with wheeled farm tractors, equipped with winch using a time motion study. Whole tree extraction system in coniferous plantation applied with typical felling system traditional has guaranteed productivity standards at a reasonable cost reducing high operational cost per unit harvested. The results, therefore, underlined that it economic possible to wood biomass harvest relatively small-diameter from thinning stands favoring moderate and heavy thinning

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

Computer vision for automatic quality inspection of dried figs (Ficus carica L.) in real-time

[EN] This work reports the development of automated systems based on computer vision to improve the quality control and sorting of dried figs of Cosenza (protected denomination of origin) focusing on two research issues. The first was based on qualitative discrimination of figs through colour assessment comparing the analysis of colour images obtained using a digital camera with those obtained according to conventional instrumental methods, i.e. colourimetry currently done in laboratories. Data were expressed in terms of CIE XYZ, CIELAB and HunterLab colour spaces, as well as the browning index measurement of each fruit, and then, analysed using PCA and PLS-DA based methods. The results showed that both chroma meter and image analysis allowed a complete distinction between high quality and deteriorated figs, according to colour attributes. The second research issue had the purpose of developing image processing algorithms to achieve real-time sorting of figs using an experimental prototype based on machine vision, simulating an industrial application. An extremely high 99.5% of deteriorated figs were classified correctly as well as 89.0% of light coloured good quality figs A lower percentage was obtained for dark good quality figs but results were acceptable since the most of the confusion was among the two classes of good product. (c) 2015 Elsevier B.V. All rights reserved.This work has been partially funded by INIA through research project RTA2012-00062-C04-01 with the support of European FEDER funds.Benalia, S.; Cubero, S.; Prats-Montalbán, JM.; Bernardi, B.; Zimbalatti, G.; Blasco, J. (2016). Computer vision for automatic quality inspection of dried figs (Ficus carica L.) in real-time. Computers and Electronics in Agriculture. 120:17-25. https://doi.org/10.1016/j.compag.2015.11.002S172512

Productivity analysis and costs of wheel cable skidder during salvage logging in European beech stand

Salvage logging is increasing in Central Europe because of the growth of severe meteorological events, and timber harvesting in these conditions is challenging in terms of both productivity performances and safety of the operations. In recent years, with the increase of natural calamities, several researchers studied machinery productivity performances regarding salvage logging carried out by ground-based systems. In fact, a common post-disturbance management approach is salvage logging which consists of the widespread removal of damaged trees. In this research, system productivity and the cost of salvage logging are analysed in European beech stands affected by wet snow. The accretion of heavy wet snow poses the greatest risk to forests in the Northern Hemisphere. This type of snow attaches more effectively to tree crowns and branches when temperatures are close to freezing at the time of precipitation. As a result, trees may break or bend and may be uprooted when the soil is unfrozen. This study has been implemented to evaluate the productivity and cost-effectiveness of extraction in salvage logging deployed with a skidder in beech stands affected by two different types of wet snow damage. The results show that the productivity of the four-wheel-drive cable skidder, despite operating in salvage cutting with a removal intensity of 10%, is 14.73 m3·SMH–1, similar to skidder performances in ‘ordinary’ cuttings. Skidder’s productive time was 86% of the scheduled time, whereas the delays were due to organisational reasons, mechanical delays, and adverse weather conditions. The mean travel speed of the cable skidder obtained in this study is close to the results obtained from other studies on similar machines. The costs per unit are lower than effective cost consumptions for the other cable skidders and agricultural tractors, adapted for skidding operated in hardwood salvage logging. Therefore, under the given conditions, the operation of the fourwheel-drive cable skidder is viable from a silvicultural, technical, and economic point of view in the salvage operation logging

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