Grapple skidder is a machine designed for the extraction of tree bunches after felling. Several factors influence its technical performance and costs such as terrain slope, operator experience time, type, size each operating cycle, among others. Thus, it becomes necessary to weigh variables that most productivity grapple skidder. So, main objective was evaluated according bunch using two feller...

The Amazon rainforest covers an area of about 50% the Brazilian national territory, which consists mainly upland rainforests that are generally poorly managed, because low investment in technology, planning, operations and manufacturing. Logging activities require a large contingent heavy machinery intense physical workload from operators crews. thermal comfort at work tropical regions is betwe...

ABSTRACT To reduce the damage caused by logging in Amazon rainforest, new metaheuristics have been implemented and tested to ensure sustainability of this economic segment. Therefore, study aimed compare alternatives for road sizing log deck allocation. In a forest management unit, skidding decks was evaluated two different areas. determine skidding/log relation, georeferenced points were gener...

The traditionally used mixed grouser of the metal track link causes a decrease in traction qualities agricultural tractor. use rear on link, our opinion, will significantly improve properties an tractor with and reduce soil destruction. When is immersed soil, additional horizontal deformation occurs, which changes law distribution along support surface trackdrive, ensures alignment shares imple...

We give a mathematical description of the initial stage both axles skidding for wheeled vehicle on bend that arises in case blocking or slipping wheels one its axles. It is shown within framework Zhuravlev’s model friction, which takes into account moments spinning friction (they appear as result interaction with reference plane), less than Coulomb model.

In this paper, a realistic simulation model for Wheeled Mobile Robot (WMR) is given by a dynamical system that switches between three models corresponding to three different tire/road contact conditions: ideal condition, skidding condition and slipping condition. Then, an algebraic based numerical identification for the discrete state (tire/road contact condition) of this switching system is pr...

in forest harvesting, there is an ongoing trend to increase constantly the size, power and load of logging machines. this may cause soil degradation in forest ecosystems as the passes of these machines modify important soil structural characteristics. the present study was conducted to examine impact of skidding traffic, trail slope, traffic frequency, and soil depth on bulk density and soil co...

Farm tractors have been applied in forest operations to carry out several tasks such as tree/felling/process-ing, forwarding, loading, skidding and cable yarding. can be equipped with special logging equipment that allows for their safe efficient work the harvesting of stands. This research is aimed collect review available literary sources on productivity farm during operations. The study resu...

Localization methods for mobile platforms are commonly based on an observation model that matches onboard sensors measures and environmental a priori knowledge. However, their effectiveness relies on the reliability of the observation model, which is usually very sensitive to the presence of unmodelled elements in the environment. Mismatches between the navigation map, itself an imperfect repre...