Early Studies of Multi-Tree Handling in Eastern Canada

Thinnings are not as common in Canada as they are in most European countries for a variety of reasons, not the least being the high treatment costs. In recent years, FERIC has proposed a host of strategies to reduce the costs of thinnings and thus increase the attractiveness of this treatment. One of these strategies is to use multi-tree handling harvester heads because the use of single-grip harvesters often results in high wood costs when harvesting small stems typical of commercial thinning treatments. Recently introduced harvester heads such as the Waratah HTH-470 HD provide multi-stem felling and processing options that can increase harvester productivity in small trees. This paper describes the early results from FERIC studies of multi-stem heads working in eastern Canada. During FERIC studies, the ability to handle more than one stem at a time increased machine productivity by an average of 21 to 33% compared with handling stems one at a time. On average, multi-stem work cycles were longer than single-stem cycles, but the ability to process more than one stem at a time in 30 to 40% of the cycles lowered the mean harvesting time per stem. The delimbing quality and the length-measurement accuracy for sawlogs were comparable to those of conventional heads currently on the market. This technology is thus well suited to final felling of small trees and to commercial thinning because its productivity is less affected than with conventional heads by the small tree volumes. The accumulator that keeps felled stems vertical also provides benefits, since it lets the operator control the fall of the felled stems and thus may reduce the risk of damaging residual stems

The role of harvester measurement in the wood supply chain

Forest industries manage their wood supply chains for sustainability, efficiency, and value creation. Roundwood measuring is a crucial part of wood procurement to achieve the best total value and sharing of benefits between business partners in the supply chain. Industrial measurement is the dominant measuring technique used in Sweden, but the use of harvester measurement has gained increasing interest over the last decade. In this study, we analyzed how harvester measurement affects the wood procurement process regarding operations, supplier relationships, and total costs. The data was gathered through interviews with the analysis being supported by theoretical frameworks of lean thinking, supplier relationship management, and total cost of ownership. Harvester measurement has the potential to increase incentives for the purchaser to preserve the value created and improve control of the supply chain, thus leading to more efficient resource use. It also improves supplier relationships due to a simpler price list, which ultimately increases transparency. Lastly, forest industries may increase their profitability levels and competitiveness due to increased supply chain surplus and reduced total costs. Further research on quantitative measures is required to assess the significance of these effects, as well as the entire sustainability impact on the wood supply chain

Operation of the Single-Grip Harvester: Motor-Sensory and Cognitive Work

This article describes the interface between a one-grip harvester and its operator as it relates to motor-sensory and cognitive activities of the operator when carrying out thinning and regeneration harvesting in Sweden. Work tasks are described, as are operator data gathering, cognitive and motor-sensory processes. Descriptions of motor- sensory inputs and control manipulation are based on digital data gathering from machine controls combined with parallel, multi-camera video taping of work activities. Work element descriptions, data gathering and cognitive processes were inferred based on interviews with 20 operators and operator instructors. Work features found to limit an operator's efficiency were: few breaks in the work; very intensive handling of controls ( 4000 control inputs per hour in our study) due to lack of automatic functions in the boom and harvester head; restricted view from the cab; lack of information about the stand and log; and skewed and twisted work postures. The main part of the operator's cognitive work was found to be done through automated skills. The experienced operator acts upon the global situation and seldom analyses it explicitly. Their chunks of information (memory aggregates recognized in toto) guide them in what to do, and usually they see only one course of action to follow in a particular situation. Key future technical development needs and opportunities include additional automation to reduce operator control inputs, developing means of improving visibility such as 3-D laser scanning and additional use of stand inventory and historical data about log properties to improve automation of cross-cutting. One of the key future research areas regarding training and robotization is to determine the data contained in the `chunks' of information used by operators in making machine location, harvesting and processing decisions

Estimation of breast height diameter and trunk curvature with linear and single-photon LiDARs

International audienceContext: Precision forestry together with new sensor technologies implies Digital Forest Inventories for estimation of volume and quality of trees in a stand.Aims: This study compared commercial LiDAR, new prototype SPAD LiDAR, and manual methods for measuring tree quality attributes, i.e., diameter at breast height (DBH) and trunk curvature in the forest stand.Methods: We measured 7 Scots pine trees (Pinus sylvestris) with commercial LiDAR (Zeb Horizon by GeoSLAM), prototype SPAD LiDAR, and manual devices. We compared manual measurements to the DBH and curvature values estimated based on LiDAR data. We also scanned a densely branched Picea abies to compare penetrability of the LiDARs and detectability of the obstructed trunk.Results: The DBH values deviated 1–3 cm correlating to the specified accuracies of the employed devices, showing close to acceptable results. The curvature values deviated 1–6 cm implying distorted range measurements from the top part of the trunks and inaccurate manual measurement method, leaving space for improvement. The most important finding was that the SPAD LiDAR outperformed conventional LiDAR in detecting tree stem of the densely branched spruce.Conclusion: These results represent preliminary but clear evidence that LiDAR technologies are already close to acceptable level in DBH measurements, but not yet satisfactory for curvature measurements. In addition, terrestrial SPAD LiDAR has a great potential to outperform conventional LiDARs in forest measurements of densely branched trees

Feasibility of Excavator-Based Harvester in Thinnings of Peatland Forests

In the next twenty years in Finland, annual cuttings on peatland forests are foreseen to increase by up to 30 % of the total cuttings. Cost effective harvesting methods on low yield peatland forests coupled with low ground bearing capacity are required. One solution to improve the feasibility of harvesting could be excavators tailored for forestry use and equipped with a harvesting head. In the study, cost competitiveness and productivity of the excavator-based harvester were investigated. The cost analysis focused on operating hours of harvester use, shift arrangements and purchase prices for the base machine and harvesting equipment when the base machine was used partly as a harvester and an excavator. Results were compared to conventional wheeled harvesters. If the base machine is used more than 3 working months as a harvester in addition to normal (6-8 months) excavator work, the harvesting method would be cost competitive compared to purpose-built harvesters (if 1½ and 2 shift arrangements were used). The 25 % increase of the base machine's and harvester equipments' purchasing costs did not eliminate the cost competitiveness of harvesting, when harvesting was carried out in 1 ½ shifts for at least 4 months. It would be feasible and profitable to invest in harvesting equipment for the excavator and therefore diminish the winter lay-days of the base machine by utilizing it in logging operations. Conditions on peatland sites mean that during the winter time the use of the excavator-based harvester is ideal, when the utilisation of all logging machines is at its highest

Development of a Sensorized Timber Processor Head Prototype – Part 1: Sensors Description and Hardware Integration

Forest operations are in constant development to provide increasingly higher standards of economic and environmental sustainability. The latest innovation trends are concentrated in the generation, storage and management of data related to the harvesting process, timber products and logistics operations. Current technologies provide productivity and position, but only physical parameters are made available for timber products. The possibility of providing a comprehensive quality evaluation of roundwood early in the supply chain and linking the information to each log provides a new tool for optimization of the whole forest-timber supply chain. Current in-field methods for grading logs are based on visual rating scales, which are subjective, operator-dependent and time-consuming. As an alternative, a sensorized processor head was developed, featuring the following sensors: near infrared (NIR) spectrometer and hyperspectral cameras to identify surface defects, stress wave and time of flight sensors to estimate timber density, hydraulic flow sensor to estimate cross-cutting resistance and delimbing sensors to estimate branches number and approximate position. The prototype also deployed an RFID UHF system, which allowed the identification of the incoming tree and individually marked each log, relating the quality parameters recorded to the physical item and tracing it along the supply chain. The tested sensors were installed and designed to be independent, nevertheless, their integrated use provides a comprehensive evaluation of timber quality. This paper presents the technical solutions adopted, the main hindrances found and some preliminary results of the operative prototype as tested in laboratory and in forest operational conditions

Virkesanskaffning med hjälp av skördarmätning : för förbättrad styrning av skogliga verksamheter

Sweden is a world-leading actor in the global forest sector and remains in the top league of trading, research, and business operations. Despite being ahead of its competitors, several forest actors struggle with low profitability levels. The profitability index for private wood suppliers decreased by 0.45 units between 2000 – 2020, and sawmills' profitability levels are still low despite investments being record high in 2018 (financial performance due to COVID-19 are not considered). Wood procurement is a decisive process for several forest actor's profitabilities. For forest owners since selling wood is the primary income from their forest, and for sawmills because a large proportion of their costs are due to the procurement. Wood procurement is a complex process, including several participants and steps to complete. Process improvements could increase profitabilities for several actors and motivate further sustainability initiatives. Studies have shown that the process along the wood supply chain can be improved with harvest measurement instead of industry measurement as payment basis. Potential in terms of reduction of lead times and improved supplier relationship are some of the findings. However, no studies have analysed whether waste can be removed and if costs can decrease by applying harvest measurement. This study identified activities, information flows, lead times, and cost drivers within the wood procurement processes of both harvest and industry measurement. It demonstrated how waste, supplier relationship, and total costs are affected by the harvest measurement and identified non-value adding activities. Furthermore, the study explored opportunities for further improvements in the process. A single case study was performed using qualitative methods. Interviews were conducted to perform a value stream map of the process, followed by an activity-based cost analysis to determine cost differences. Lastly, further process improvements were explored by combining the empirical findings with the latest research and development within wood procurement. The result showed that harvest measurement as payment basis enable more flexible management of the logistics and bucking instructions. Overprocessing waste during contracting and making of the final invoicing is reduced. The supplier takes less risk and the cash flow is improved. On the other hand, the buyer takes a higher risk and gets a weakened cash flow. Measurement at the industry becomes non-value-adding. Lastly, lead time from harvest to supplier’recives his payment is reduced by half from eight to four weeks when harvest replaces industry measurement as payment basis. the main reasons for the differences are the change of ownership in the value chain, and the push flow becoming a pull flow in the end of the process when harvest measurement is applied as payment basis. The activity-cost analysis indicates that the supplier’s sales costs increase by 1.7 kr/m3ub, and the acquisition cost for the buyer is reduced by 7.5 kr/m3ub. Moreover, applying a digital contracting and planning process could reduce the acquisition cost further since a lot of the cost originates from time spent on these activities.Sverige är en världsledande aktör inom den globala skogsindustrin och återfinns bland världens främsta inom handel, affärsverksamheter och forskning. Trots en välutvecklande skogsindustri så är lönsamheten låg för flera aktörer. Skogsbruksindexet sjönk med 0.45 enheter mellan 2000 och 2020 för privata skogsägare, samtidigt som sågverks lönsamhet förblir låga trots rekordhöga investeringar under 2018 (finansiellt resultat till följd av COVID-19 ej medräknat). Virkesanskaffning är en avgörande process för flera skogsaktörers lönsamhet. Dels för att virkesförsäljning är skogsägares främsta intäkt från skogen, dels för att virkesanskaffning är en av de främsta utgifterna för sågverk. Virkesanskaffning är en komplex process och förbättringar inom processen skulle kunna leda till ökad lönsamhet för flera aktörer och motivera för ytterliga hållbarhetsarbete. Studier har visat att virkesanskaffning kan förbättras genom att tillämpa skördarmätning som betalningsunderlag i stället för industrimätning. Inga studier undersökt skillnaderna i processen för att avgöra om slöseri kan minskas och hur de totala kostnaderna påverkas genom att tillämpa skördarmätning. Denna studie identifierade aktiviteter, informationsflöden, ledtider och kostnadsdrivare inom virkesanskaffningsprocessen med skördar- respektive industrimätning. Studien demonstrerade hur slöseri, leverantörsrelationer och totala kostnader påverkas när skördarmätning tillämpas som betalningsunderlag, samt aktiviteter som blir icke värdeskapande. Därtill utforskade studien hur virkesanskaffningsprocessen kan förbättras ytterligare. En fallstudie baserat på kvalitativa data genomfördes för att uppfylla syftet, med stöd av teorier kring verksamhetsstyrning. Intervjuer genomfördes för kartläggningen av värdeflödet inom processen, följt av en aktivitetsbaserad kostnadskalkyl för att identifiera kostnadsskillnader. Slutligen utforskades möjliga förbättringar av processen med hjälp av studiens empiriska fynd tillsammans med senaste forskningen och utvecklingen kring virkesanskaffning. Resultaten visade att skördarmätning möjliggör en flexiblare styrning av virkeslogistiken, samt att apteringen kan bättre styras för att möta industrins efterfrågan. Skördarmätning leder till minskat överbearbetnings slöseri under kontrakteringen och slutredovisningen. Leverantören tar en mindre risk och får ett bättre kassaflöde medan köparen tar högre risk och får ett sämre kassaflöde när skördarmäning används som betalningsunderlag. Mätning vid industrin tillför heller inget värde för affärsledet mellan leverantör och inköpsorganisationen när skördarmätning används som betalningsunderlag. Skördarmätning leder även till halverad ledtid från avverkning till utbetalning, reducerad från åtta till fyra veckor. Den aktivitetsbaserade kostnadskalkylen tyder på att leverantörens försäljningskostnader ökar med 1,7 kr/m3 fub och köparens anskaffningskostnader reduceras med 7,5 kr/m3 fub när skördarmätning tillämpas. Att applicera en digital plattform för kontrakteringsprocessen, och en digitaliserad traktplaneringsprocess skulle kunna reducera anskaffningskostnaderna ytterligare då en stor del av kostnaden härstammar från tiden spenderat på dessa aktiviteter

Cut-To-Length: The Next Decade

This article discusses the logging system where the logs are made at the stump from a harvester and carried to the landing by a forwarder. The focus is on Sweden, yet with international outlooks. Trends in forestry in the last decades are described and used to envision the next decade. In our analysis we consider the call for sustainable forest management, the demand and supply on the wood market, system productivity and utilisation, as well as operational organisation, operator education, health and safety and technical development. A comparison is made between three mechanised logging methods as well as between three different forest worker education systems. Hindrances found when introducing cut-to-length are operator education, work crew organisation, supply of maintenance service and capital bound in other logging systems. The trend towards purpose built harvesters is discussed. The possibilities following advanced electrohydraulics and GPS/GIS are discussed regarding machine control, maintenance, operational planning and supervision