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

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.

Operating Parameters and Environmental Indicators of Diesel Engines Fed with Crop-Based Fuels

A comparative analysis of performance of Diesel engines fuelled by diesel oil, methyl ester of rapeseed oil and raw rapeseed oil was performed. The analysis of external characteristics of engines powered by various fuel types was accepted for an assessment. Engine performance rates were analysed while attention was paid to power courses, moment, unit fuel consumption and hour fuel consumption, exhaust fumes temperature and exhaust smoke. Operation effectiveness of engines was assessed when they were fed with various fuel types and optimal proportions of fuel mixtures were indicated. Environmental aspects of powering the engines with traditional fuels and crop-based fuels were analysed. The total CO2 emission in the entire process of manufacturing and combustion of fuels was accepted as a criterion. A simplified economic analysis was performed in the aspect of the underlying purpose of using crop-based fuels for propulsion of piston engines. Conclusions and recommendations that indicate directions of development concerning the analysed issue were prepared.

Employment characteristics of tine cultivators at deeper soil loosening

The work quality of selected tine cultivators that are suitable equally for deeper soil cultivation has been evaluated. The following implements were tested in a stubble field: Köckerling Vario 570, Simba Solo 450, Horsch Terrano 5 FX, Strom Finisher Mega 8000, Farmet Turbulent 450, Kverneland CLC 430, Väderstad TopDown 400. The cultivator evaluation criteria were the following: quantity of plant residues left on the soil surface, size distribution of clods, transverse elevation profile of the soil surface, elevation profile of the furrow bottom, cultivation depth, unit fuel consumption, travel reduction ratio, work-rate, and unit draft of a cultivator. All of the cultivators were equipped mainly with tine tools, followed further on by disc tools and either by levelling or by crumbling tools. Plant residues were well worked into the soil by Väderstad and Farmet cultivators. Horsch, Kverneland and Väderstad cultivators showed good crumbling effect. The highest work speed was reached by tractors with Strom and Horsch implements.

Comprehensive Product Platform Planning (CP3) for a Modular Family of Unmanned Aerial Vehicles

The development of products with a modular structure, where the constituent modules could be derived from a set of common platforms to suit different market niches, provides unique engineering and economic advantages. However, the quantitative design of such modular product platforms could become significantly challenging for complex products. The Comprehensive Product Platform Planning (CP3) method facilitates effective design of such product platforms. The original CP3 method is however typically suitable for scale-based product family design. In this paper, we perform important modifications to the commonality matrix and the commonality constraint formulation in CP3 to advance its applicability to modular product family design. A commonality index (CI), defined in terms of the number of unique modules in a family, is used to quantify the commonality objective. The new CP3 method is applied to design a family of reconfigurable Unmanned Aerial Vehicles (UAVs) for civilian applications. CP3 enables the design of an optimum set of distinct modules, different groups of which could be assembled to configure twin-boom UAVs that provide three different combinations of payload capacity and endurance. The six key modules that participate in the platform planning are: (i) the fuselage/pod, (ii) the wing, (iii) the booms, (iv) the vertical tails, (v) the horizontal tail, and (vi) the fuel tank. The performance of each UAV is defined in terms of its range per unit fuel consumption. Among the best tradeoff UAV families obtained by mixed-discrete Particle Swarm Optimization, the family with the maximum commonality (CI = 0.5) required a 66% compromise of the UAVs’ range/fuel-consumption performance. The platform configuration corresponding to the maximum-commonality UAV family involved sharing of the horizontal tail and fuel tank among all three UAVs and sharing of the fuselage and booms among two UAVs.