Brooks Automation
P/N: PFD0-DI-00010, Rev 5.0.0, April 9, 2022
Introduction to the Hardware
Copyright © 2022, Brooks Automation, Inc.
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In Computer Mode, the robot can move quickly. The PFDD robots have been designed to be “hand-safe”
even in computer mode, and in some cases a risk assessment of the application may indicate that it can
be used without operator safety screens. However, safety glasses should be worn at all times when an
operator is within the robots working volume. Please refer to the EN ISO 10218-2-2011 Robots for
Industrial Environments, Safety Requirements for information on recommended safe operating practices
and enclosure design for robots of various sizes and payloads.
Mechanical and Software Limit Stops
All joints have hard limit stops at the end of travel which are factory installed. The soft-limit stops must be
set within the range of these hard stops. The wrist axis in the PFDD4 has a slip ring when the electric
gripper is installed, al/- 240 degrees rotation. Since the robot has absolute encoders with battery
backup, even if the robot is turned off, the encoders keep track of joint position. The joint position can be
viewed either on the optional Manual Control Pendant, or in the Virtual Manual Control Pendant in the
Web Based Operator Interface. (See Guidance Controller Setup and Operation Quick Start Guide).
Stopping Time and Distance
The robot control system responds to two types of E-Stops.
A Soft E-Stop initiates a rapid deceleration of all robots currently in motion and generates an error
condition for all GPL programs that are attached to a robot. This property can be used to quickly halt all
robot motions in a controlled fashion when an error is detected. A soft E-stop is typically generated by an
application program under conditions determined by the programmer.
This function is similar to a Hard E-Stop except that Soft E-Stop leaves High Power enabled to the
amplifiers and is therefore used for less severe error conditions. Leaving power enabled is beneficial in
that it prevents the robot axes from sagging and does not require high power to be manually re-enabled
before program execution and robot motions are resumed. This function is also similar to a Rapid
Deceleration feature except that a Rapid Deceleration only affects a single robot and no program error is
generated.
If set, the
SoftEStop
property is automatically cleared by the system if High Power is disabled and re-
enabled.
A Hard E-Stop is generated by one of several hardware E-Stop inputs and causes motor power to be
disabled. However, there is a parameter that determines a delay between the time the Hard E-Stop
signal is asserted and the time the motor power supply relay is opened. This delay is nominally set at 1.0
seconds. It may be adjusted by an operator with administrator privileges. On the web-based operator
interface menu, go to Setup/Parameter Database/Controller/Operating Mode/ and set parameter 267 to
the desired delay. If this delay is set to 0, the motor power will be disabled within 1ms.
For the PFDD6 robot, the base rotation, elbow, and J6 axes do not have mechanical brakes. For the
PFDD4 robot, the base rotation, elbow, and J4 axes do not have mechanical brakes. Therefore, leaving
the motor power enabled for 1.0 sec allows the servos to decelerate the robot. The servos are set to
decelerate the robot at 0.015G, or 150mm/sec
2
. If the robot is moving at a joint speed of 100
