Contents of Journal of Mechanical Engineering 58, 2 (2007)
NALITOLELA, N. G., MSHANA, J. S.: Structural modelling and the
application of response surface modelling for engine design
optimisation 57
KELEMEN, M., KELEMENOVÁ, T.: Identification of friction
forces in the in-pipe micromachine 71
FENIK, Š., STAREK, L.: Piezoceramic actuator and sensor
for vibration control 85
Letter to the Editor
SU, S., ERKAYA, S., UZMAY, I.: Transmission quality and
kinematics of a new slider-crank mechanism 106
Abstracts
Structural modelling and the application of response surface modelling for
engine design optimisation
NOEL G. NALITOLELA, JOHN S. MSHANA
Structural design optimisation of internal combustion engine is usually performed
iteratively using finite element model and employing gradient-based methods. Finite element
re-analysis, however, is computationally expensive. This paper presents an alternative
procedure to model the engine performance parameters using response surface modelling
methodology (RSM) as an efficient approach where re-analysis is required. The procedure
involves finite element modelling of the engine structures to predict performance at only a
few selected points in the design space, and use of response surface modelling approach to fit
a model to the predicted performance parameters. Then instead of the finite element re-analysis,
performance of the iterated design is obtained more efficiently using the response
surface model. The effectiveness of the response surface model to predict performance of the
iterated design is investigated on the crank train and block interaction parameters of a
practical engine.
Identification of friction forces in the in-pipe micromachine
MICHAL KELEMEN, TATIANA KELEMENOVÁ
The paper concerns the in-pipe micromachine Karolina, locomotion of which is based
on the inertial stepping principle. The aim of the micromachine is to inspect and to do other
tasks inside the pipe. The paper describes the methods of friction forces identification.
Several experimental results applicable at the analog machine assembling are specified here.
The paper is a part of research grant GU VEGA 1/2188/05 Research of in-pipe machine
locomotion principle in order to cable drawing into existing pipes and GU VEGA 1/4164/07
The research of the specific problems in area of distance measurement and measurement
uncertainty balancing.
Piezoceramic actuator and sensor for vibration control
ŠTEFAN FENIK, LADISLAV STAREK
Application of piezoceramic elements as actuators and sensors in
vibration control should be prepared with suitable mathematical background.
Only correctly simplified model of smart structure is useful for further
optimization and control design. In this paper authors present their contribution
in the field of linear mathematical modelling of mechanical structures with
implemented piezoceramic elements, including relations for calculation of
actuator force, sensor voltage and capacitance with respect to boundary
conditions. Theoretical conclusions are verified by FEM simulation of
piezoceramic element attached to a surface of structure and some practical
questions are discussed.
Transmission quality and kinematics of a new slider-crank mechanism
SÜKRÜ SU, SELÇUK ERKAYA, IBRAHIM UZMAY
In this study, kinematic analysis and transmission quality of a modified slider-crank
mechanism are investigated. The new mechanism has a gear system and an additional eccentric link
between connecting rod and crank pin as distinct from an original slider-crank mechanism. These
modifications were performed with a view to ensure the effective usage of gas forces during the
expansion stroke for obtaining the effective output torque. With the intending of comparing,
kinematic analysis and transmission angle results of the new mechanism have been evaluated with
respect to that of an original slider-crank mechanism with the same stroke and same rotation speed
of the crankshaft.