Abstract— This paper presents the distributed control
system for elevators (DECS). Based on the characteristics of
the today installed elevator systems, the electric traction
elevator has been chosen for this paper. Conventional elevator
control systems (ECS) have several disadvantages compared to
modern control systems (large number of cables, safety issues,
etc.). An alternative to conventional ECS is the DECS. A
DECS based on the CAN (Controller Area Network) protocol
is presented in this paper. The presented ECS consists of three
modules: CU Elevator (CU – Control Unit), CU Cabin, CU
Floor. The mentioned modules, control principles and
implementation methods based on the PIC 18F458
microcontroller are presented in detail. A description of the
CAN protocol design with message scheduling on the bus is
given. Messages with an 11 bit identifier without a data field
have been used for the distributed control system synthesis.
The time analysis of bus availability/traffic demonstrates the
adequacy of the distributed control system Based on the
defined messages and 5 presented modes of operation, an
algorithm of operation has been formed for every control
system module. Finally experimental results are presented
that have been obtained from a developed CAN based elevator
control system. The conducted tests have confirmed the
functionality of the elevator control system.
I. INTRODUCTION
HE first electrical controls were realized by relay
techniques. In the 1970's the principles of relay
equipment were applied to electronic controls [1]. The first
completely microprocessor-based control system was
developed in the beginning of the 1980's [2]. We have
improved electrical control system of a relay-controlled
elevator in a residential building by using PLC [3].
The distributed elevator control system is replaced the
centralized control system on the based microprocessor
and/or PLC, and become the dominant equipment of
electronic system automatization in last 10 years.
Distributed elevator control system is created from several
Manuscript received January 31, 2010.
S. Huseinbegovic is with the Faculty of Electrical Engineering, Department
of Automatic Control and Electronics, University of Sarajevo, 71000
Sarajevo, Bosnia-Herzegovina (e-mail: s.huseinbegovic@etf.unsa.ba).
S. Kreso is with the Faculty of Electrical Engineering, Department of
Automatic Control and Electronics, University of Sarajevo, 71000 Sarajevo,
Bosnia-Herzegovina (e-mail: sarfo@bih.net.ba).
O. Tanovic is with the Faculty of Electrical Engineering, Department of
Automatic Control and Electronics, University of Sarajevo, 71000 Sarajevo,
Bosnia-Herzegovina (e-mail: omer.tanovic@etf.unsa.ba).
independent intelligent control units/modules/stations.
Control units is possible to realized with single
microcontroller/microprocessor units, PLC, embedded
computer or PC [4]-[7].
Today trend in industry control elevator system is
designed the distributed elevator control system on the
based microcontroller/microprocessor or FPGA.
This paper is divided into six sections. The second
section introduces the architecture of our DECS, and some
detailed features of the elevator systems. The third and
fourth sections present the hardware structure of module
DECS based on microcontroller PIC 18F458 and CAN bus
and software flow chart. Some experimental results are
provided in the section five. The conclusion is made in the
section six.
II. DECS ARCHITECTURE
The technical characteristic of an elevator system are:
The elevator system consists of a single/double cabin with
64 floors. On each floor there is a request one or two button,
a control light and a display for the direction of travel
indication and the current position of the elevator cabin.
The sensors for the current position and the
acceleration/deceleration of the elevator cabin are located
on each floor. The cabin has a single/double door, which
can be opened/closed manually, ½ automatically or
automatically. During the cabin movement doors have to be
closed. Two sensors inform the control system about the
door position. An optical sensor can detect objects while the
door is closing. In the elevator cabin there is a panel with
request button, control light and a display for the direction
of travel indication and the current position of the cabin.
The elevator cabin engine moves the cabin up and down.
Limitation of cabin movement is realized using two limit
switches for top and bottom elevator positions (safety
switches).
Fig.1. shows the architecture of distributed elevator
control system (DECS), proposed by the authors. The basic
components of the elevator control system are: CU Elevator
(CUE), CU Cabin (CUC) and CU Floor (CUF) (CU stands
for Control Unit). All above mentioned modules are
microcontroller based structures. For the realization of
DECs Microchip PIC 18F458 microcontroller was used.
Development of a Distributed Elevator Control System Based
on the Microcontroller PIC 18F458
S.Huseinbegovic, GSM, IEEE, S.Kreso, Member, IEEE, and O.Tanovic, GSM, IEEE
T
978-1-4244-7623-7/10/$26.00 ©2010 IEEE
858 IEEE Region 8 SIBIRCON-2010, Irkutsk Listvyanka, Russia, July 11 — 15, 2010