Evaluation of an HSM 208F 14tone HVT-R2 Forwarder Prototype under Conditions of Steep-Terrain Low-Access Forests

Abstract

Forwarding technology is well established in use around the world but, at the same time, forwarders are expensive machines that require a good planning to ensure the sustainability of operations. In addition, forwarder market is characterized by a limited pool of customers, therefore innovation attempts may be limited compared to other product development industries. Since the steps towards a full automation of operations are still at their beginning, improvements of forwarder machines may rest in developing and integrating components that could contribute to an increased effectiveness. To respond to such challenges, the Forwarder2020 project developed innovative components that were integrated in a number of forwarder prototypes based on a market pull approach that resulted in a flexible adaptation to customer requirements and work environments. Since one of the typical work environments was that of low access forests, some components (i.e. suspended cabin and transmission system) were engineered to enable faster and safer operations and to economize fuel. As a common validation step is that of bringing field evidence on the performance improvement, this study evaluated the operational speed, productivity and fuel consumption of a forwarder prototype in conditions of a steep-terrain low-access forest. The main findings were very promising as the prototype was able to operate at significantly increased speeds and the fuel savings were evident. For an average forwarding distance of about 1.5 km, net productivity and efficiency rates were estimated at 14.4 m3/h and 0.07 h/m3, respectively. They were related to the availability of wood, and further improvement of such figures is possible by a better organization of tree felling and processing. Operational speed was affected by the condition of skid roads used for forwarding, which were harsh. During the transportation tasks developed on roads typical for forwarding, the machine was able to sustain average speeds estimated at 8 km/h. As a matter of fact, in such tasks, the dominant operational speed (almost in 100% of the cases) was higher than 5 km/h irrespective of the road condition. Hourly fuel consumption was estimated based on the time in which the engine was working and it amounted to 17.1 l/h. More importantly, by considering the forwarded payload in terms of volume and mass, the unit fuel consumption was estimated to be 1.25 l/m3 and 1.47 l/t, respectively. These results bring evidence on the performance improvement by modular innovation. In fact, such solutions could answer the challenges related to the sustainability of forest operations in low access forests.

Modelling Productivity in Extraction Operations by Simulations Based on GNSS Documented Data: An Example from Skidding Teak Wood In Thailand

“…GPS speed extracted from handheld units has been proved to be useful in many applications of forest engineering [2,3,5,17]. In this study, it was used for simulation, based on the average values returned by a detailed analysis of the observed events.…”

“…Location data was exported from the GPS unit in the form of a GPX file which was loaded in Garmin® Base Camp® software with the main aim of extracting data on speed to be analyzed in Microsoft® Excel®. Data extraction and processing procedures used to get the speed data in the form of numbers were similar to those reported by [2,3,6]. The recorded GPS track was analyzed in the software's running mode to detect the events observed in the field.…”

“…[17]. Based on our experience, the use of handheld GPS units in forest operations was able to provide useful information for dedicated studies [2,3,5]. Average speeds returned by the statistical analysis for entry-exit (EES, km/h), maneuvering (MS, km/h), empty (ETS, km/h) and loaded (LTS, km/h) turn events were used as a baseline to plot productivity against the extraction distance, which was considered to be the most relevant factor affecting productivity.…”

“…The cut to length (CTL) can be used in thinning, where for the extraction of small logs one can use manpower, mule, or log chutes [15]. The TL method includes basic manual work, where felling, delimbing, and toping, are the motor-manual activities done in harvesting area; these may be performed at productivities of 30 m 3 /PMH, where the stem volume is 0.86 m 3 and the harvesting stock is 130-170 m 3 /ha [19]. The felled stems are extracted and placed in bundles at the landing area.…”

Seasonal Variation of GPS Accuracy and Precision in Forest Road Mapping

“…Objects between the satellite and the receiver such as mountains or tree canopy in forested areas can produce errors. GPS receivers are frequently used for engineering activities in forest environments such as locating or mapping boundaries, monitoring harvesting machinery [6], [17], [23], running topography and cadastral forest surveys [37], supporting forest inventories [11], running forest engineering and resource management activities [43], delimitating forest areas and estimating perimeters [38], as well as in integrating GPS data in geographic information system (GIS) applications [41].…”