April 01, 2014
DC SERVO DRIVER
There
are a lot of motor types that were intergrated in many devices, robots,
automatic systems….DC motor is very popular actual with better characties than
the other motors.
The
project used MCU PIC18F4620, TI LM629-N and single channel H-Bridge to control
directly a position round of DC motor
The
LM628/LM629 are dedicated motion-control processors designed for use with a
variety of DC and brushless DC servo motors, and other servomechanisms which
provide a quadrature incremental position feedback signal. The parts perform
the intensive, real-time computational tasks required for high performance
digital motion control. The host control software interface is facilitated by a
high-level command set. The LM628 has an 8-bit output which can drive either an
8-bit or a 12-bit DAC. The components required to build a servo system are
reduced to the DC motor/actuator, an incremental encoder, a DAC, a power
amplifier, and the LM628. An LM629-based system is similar, except that it provides
an 8-bit PWM output for directly driving H-switches.
User
set the parameters (trajectory, velocity, aceleration…) then click RUN command
to the mainboard. In process of running, driver will send feedback signals that
were drawn on chart to show user can follow and control.
Full view
Power Regulator,
MCU, LM629, Shift data IC, USB interface, Crystals, Isolators……….
Top view
DC motor and 334
x 4 pulse Encoder
Control Center
H-Bridge with
Heat-sink cooler
Tittle
MiniUSB
connector, Main supply(left-side jack) and Power supply(right-side jack)
Motor is running
Process Complete
Base on respoding of motor's signal on diagram, We also can calculate to find other parameters like rising time, max torque, max round, available PID parameters by tuning the servo.