It is known that means of transport are vehicles whose specific features depend on the conditions in which they perform their main function – i.e. transportation of goods load and passengers in space. The condition and the kind of transport is determined by the specialization of the means of transport.

The present works investigate the operating efficiency of the subclass of means of transport known as lift-load trucks. The set of features of transport means which determine the fit-up degree of its construction to operate at certain conditions are called operating conditions.

The systematic study of the operating conditions of lift-load trucks and the evaluation of the influence of a vehicle’s engineering parameters on lift-load trucks is of high priority. It allows the optimization of lift load trucks characteristics at the stage of their design and, as consequence, enables the creation of the most rational designs and their use under specific operating conditions providing maximum operating efficiency.

Features of transport means are revealed in the interaction with elements of the system between the vehicle, the driver, the moving surface and the surroundings and, consequently, operating efficiency of transport means - is its effective use at certain operating conditions.

The operating efficiency of the means of transport is influenced by :

the vehicle’s parameters (mass and position of its center in longitudinal and horizontal cross-surface, the overall vehicle dimensions, its volume and standard items

the technological cycle with the use of transport means (rational diagram and operating technological process level, transportation shoulder)

the characteristics of processing vehicle (processing performance of load, vehicle moving performance with and without load, maneuver and transport parameters

the general characteristics of the vehicle’s overall performance; reliability of the vehicle and its parts; the maximum use of auxiliary devices for load processing, the ergonomic index (i.e. visibility, conditioning, handling simplicity, vehicle storage and maintenance)

external influences on the vehicle (road condition, professional driving, environment).

Thus, the operating efficiency of lift-load trucks – i.e. their optimum usage under certain operating conditions (interaction between carriage-speed properties with fuel savings under certain movement conditions). Thus, the main aim of this work is the further analysis and determination of measures which would increase the operating efficiency of lift-load trucks. Considerable contribution to the development of this trend have been made by J.Machulski, P.Hashtchuk, Y.Ros’.

The problems pertaining to the influence of the following parameters on the operating efficiency of lift-load trucks have been solved :

dimensions of load

peculiarities of cycles of its work

general characteristics of the vehicle

external influence.

The scientific novelties introduced by the current paper are as follows:

a mathematical model which allows the analysis of the influence of the below mentioned parameters on operating efficiency of lift-load trucks

solving procedure of non-linear systems of integral differential equations of mathematical model

the procedure of three-staged approbation of mathematical model

new results of calculations taken by means of model.

Practical usefulness of the work are considered to be:

an applied kit of computer programs that makes the automatic control of research work possible

the results of research on the basis of which recommendations for increasing the operating efficiency of lift-load trucks improvement have been made

the determination procedure of the operating efficiency of lift-load trucks at operating conditions

ways of improvement of operating efficiency of lift-load trucks and the number of constructive solving applied to lift-load trucks with an experimental fork lifter

new technological processing of load

testing procedure of new models of lift-load trucks that come to the production.

Personal submission of the researcher includes the systematization and analysis of parameters that influence the operating efficiency of lift-load trucks, work out of mathematical operating and movement model of lift-load truck, the creation of applied programs and three-stage approbation and getting new results that add to the researched problem as well as the determination procedure of operating efficiency of lift-load truck at working cycle.

The researcher has suggested the ways of increasing operating efficiency increasing of lift-load trucks (the constructive decisions of realization of these ways have been carried out) new technologies for load handling and procedures for testing of new engineering items have been developed.

Approval of cermets: the results of the dissertation have been discussed at the International Conference “Sakon ‘92’: Metody obliczeniowe i badawcze w rozwoju systemow pojazdow i maszyn“ (Rzeszow, 1992); International Scientific and Practical Conference “Forest Transport in the Carpathians; traditions, realities and prospects” (Lviv,1998); International Scientific Conference in Mechanics ’98 (Rzeszow,1998); 4-th International Symposium of Ukrainian Engineer-Mechanics (Lviv,1999).

Publications. The author has published 24 publications (including 3 International Conference reports; 12 claims and patents ; 4 publications; 5 personal publications).