Renesas RX24T Reference Manual

Reference Guide for a 2-Axis Robot Arm with 2-Phase Stepping
Motors Incorporating Resolvers
RX24T, RX72M, RAA3064002GFP/RAA3064003GFP
Overview
We have developed a reference kit for a 2-axis robot arm
with our solution for positional control involving the use of
2-phase stepping motors incorporating resolvers.
An RX72M handles the numerical control and two
RX24Ts handle motor control of the axes. The system
enables movement of the arm at speeds of up to 250 mm
per second within the movable range of 150 mm x 153
mm.
Features
• Trajectory control of the arm (CP control)
 Continuous path (CP) control by linear or circular
interpolation enables consecutive operations along
the path as required (a demonstration video is
available on the Renesas website).
 Arm swing speed is adjustable from low to high
(0.017 to 5 r/sec)
 Motor control for axes: The RX24Ts control the
motor positions by using the resolver feedback
signals (servo control).
 System control: The RX72M controls the robot arm
as a whole, with each of the segments controlled
by an RX24T.
High positional resolution of 200,000 P/R
•
 A positional resolution of 200,000 pulses per
revolution is achieved by using 2-phase stepping
motors incorporating resolvers manufactured by
MinebeaMitsumi Inc. and resolver-to-digital
converters (RDC ICs) manufactured by Renesas
Electronics.
 Repeatable positional accuracy: 0.2 mm
 The positional resolution is 250 times that
achievable by open-loop control
Reducing the reference kit's size by integrating the
•
mechanical and electrical structures
 Integral structures with the control boards installed
at the opposite ends of the stepping motors from
the driving ends of the motor axes.
 Only requiring the power supply and
communications lines reduces the amount and
complexity of wiring.
R01AN5644EJ0100 Rev.1.00
Jan 22, 2021
◆GUI（PC）
・Training
・Running the
demo system
USB
◆NC board
Ethernet
・Trajectory control
Interpolation calculation (linear interpolation or circular interpolation)
Acceleration or deceleration calculation (moving average filter)
RX72M Joint angle calculation (successive Jacobian calculations)
RX72M
Monoaxial movement (no interpolation or angle specification)
・ Consecutive operations (combinations of motion in straight lines and along arcs)
◆Communications
Modbus communications at 1 Mbps with the use of half-duplex RS485
Arm 2
Arm 1
RX24T
RX24T
RX24T
RX24T
• Gearless direct drives
 Direct drives with high positional resolution
eliminate being out-of-step with the resolver
positional information and maximize the motor
torque.
 The RX24Ts apply filtering to suppress the
mechanical resonances caused by the direct
drives.
 The gearless structure reduces system costs.
High-speed serial communications
•
 Modbus communications at 2 Mbps with the use of
half-duplex RS485
Applications
Service robots
•
Small arm robots
•
Power-assistance robots
•
XY-stage driving
•
• Automatic guided vehicles
• Electrically driven slides
• Surveillance camera positioning
• Machine tool control
• Textile-related machinery
• Medical equipment
•
OA equipment
◆Motor in use
・2-phase stepping motor
◆Resolver
・Position resolution of 200,000 P/R
◆Motor control
・Vector control of position, speed, and current
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