ELECTRONICS
CONTROL TECHNOLOGIES
Understand and
implement
THE IMPORTANT CANBUS FEATURES THAT
DESIGNERS AND BUILDERS OF INDUSTRIAL
MOBILE MACHINERY NEED TO KNOW ABOUT
mobile machinery – and in a wide range of other
vehicles – to connect control and sensing
technologies together. In this way they can
communicate, recording and transmitting data
without the need for a central ‘host’ computer.
‘Industrial mobile machinery’ is a broad term,
but CANbus is extremely versatile. Machinery
for which CANbus is suitable ranges from
off-highway vehicles such tractors, lawn mowers,
forklifts, cranes and bulldozers through to static
machinery like industrial robots and automation.
Such machinery may incorporate almost any
control and sensing technologies such as servo
drives, high-speed analogue and digital sensors,
fluid power systems and safety related control
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CANbus is one of the main
communication buses used in industrial
iVT International Off-Highway 2020
systems. CANbus enables them to connect
and communicate.
CANbus: CAN and CAN-FD
CAN (controller area network) is a serial
communications bus for bidirectional
transmission of control system data. Connections
between control units and input/output (I/O)
devices are typically made using a two wire,
twisted-pair cable that enables data rates of up to
1 Mb/s to be achieved, depending on the bus
length, with 8-byte data packets.
CAN FD (CAN with flexible data-rate)
is an extension to the CANbus protocol. It was
created for accurate ‘real-time’ data. It enables
data transmission up to 8Mb/s with data packets
of 64 bytes.
CANbus benefits from guaranteed latency,
excellent error detection, cost effective hardware
and efficient installation.
What CANbus offers machine builders
CANbus is a multi-master protocol, so lends
itself particularly well to decentralized control
systems, which are becoming increasingly
popular. Machines can be electrically noisy
environments due to the presence of electric
motors and switchgear, but this is not a problem
for CANbus because it can achieve robust and
reliable communications while still delivering
high performance and near-real-time (CAN) or
real-time (CAN-FD) feedback for deterministic
control systems. CANbus systems are
straightforward to modify or expand, which