HC Robots Wall Mounted or Inverted – Arm Control

Introduction

When an HC robot is inverted or wall mounted, additional settings are needed to run the HC robot without hitting any PFL alarms or issues. In this article it will explain how to set up an HC robot to be wall mounted or inverted, through Arm Control Settings.

The HC30PL is the only HC robot that is NOT compatible to be wall mounted or inverted. The HC30PL can only be floor mounted, on a flat/straight floor (Angle of 0°, Relative to the Ground).

Overview

When an HC robot is inverted or wall mounted, Arm Control needs to be set appropriately to tell the robot controller how the actual HC robot is mounted. Doing so, the robot controller will be able to counter interact the force of gravity acting on the HC robot and not suspect that gravity is an unexpected external force that’s being acted on the robot.

Settings

To set up Arm Control, the user navigates to the Main Menu → ROBOT → ARM CONTROL. Verify that the robot controller is in MANAGEMENT Mode Security Level or higher, to access Arm Control.

Arm Control can be found in the Main Menu → ROBOT → ARM CONTROL.

In the ANGLE REL. TO GROUND section is where the angle is set, depending on how the HC Robot is mounted.

The example above shows how to determine the Robot Installation Angle for Arm Control setup.

The image above shows different robot mount angles, and their respective angles, that will be set in the ANGLE REL. TO GROUND section of the Arm Control Screen.

Arm Control with PFL

Arm Control Settings is applicable to HC robots and non-HC robots, such as GP or AR robots. For HC robots, if the robot is inverted or wall mounted and Arm Control is NOT setup, the torque sensors will NOT detect forces correctly. It can cause the HC robot to trip PFL alarms more easily or constantly, even if the tool data was set correctly, using tool data from CAD, and/or recalibrating the torque sensors with the correct tool data.

When the HC robot is floor mounted (Angle of 0°, relative to the ground) the robot controller is expecting gravity to be acting in the Z- direction, as shown below:

An HC20DTP mounted to the floor and the mount/installation angle set to 0° in Arm Control.

When an HC robot is mounted to a ceiling (inverted), and the mount/installation angle is NOT set to 180° in Arm Control, the robot controller will be expecting gravity to be acting in the opposite direction of the actual direction of gravity. This is seen in the image below:

An HC20DTP mounted to a ceiling (inverted), with Arm Control NOT set correctly.

The robot controller doesn’t know how the robot is physically mounted unless it’s told through Arm Control. In the case of the HC20DTP being mounted to a ceiling (inverted), the robot controller is still expecting gravity to be acting on the Z- direction with respect to the robot’s XYZ coordinates.

Not setting up Arm Control properly will cause the torque sensor to believe that the force from gravity is an irregular external force acting on the robot, which can be seen in the Force Monitor Screen. In the Force Monitor, the user will see an unexpected force value in the Z direction, where gravity is acting on the robot. To navigate to the Force Monitor, go to the Main Menu → SAFETY FUNC. → ForceMonitor.

Not setting up the mount/installation angle of the robot in Arm Control properly can cause alarms such as Alarm 6004: ESCAPE FROM CLAMPING ERROR(PFL), Alarm 6005: EXTERNAL FORCE ERROR(PFL), Alarm 6022: EXTERNAL FORCE ESTIMATION ERROR, etc. These alarms can occur in either TEACH mode, when programming a job or in PLAY mode when running a job. Below is an image of a customer’s pendant with these alarms when the robot’s mount/installation angle was NOT set properly in Arm Control.

Several alarms on a customer’s HC10DTP that is mounted to the ceiling (inverted). The root cause of these alarms was Arm Control NOT set correctly.

To prevent PFL alarms and issues to the HC robot, set Arm Control correctly. In the example below, the HC20DTP’s mount/installation angle is set to 180° in Arm Control and the robot controller knows that gravity is acting in the Z+ direction, with respect to the robot’s XYZ coordinates.

An HC20DTP mounted to a ceiling (inverted) with the mount/installation angle set to 180° in Arm Control. Now, the robot controller is expecting the force from gravity to act on the HC20DTP on the Z+ direction of its XYZ coordinate system, which is the same direction that gravity is acting on the HC20DTP.

Conclusion

Having an HC robot wall mounted or inverted, verify Arm Control is set properly. NOT doing so can cause alarms on the robot controller and can wear out the robot faster. Arm Control settings are applicable to non-HC robots, such as the GP robot or AR robots. For additional information on Arm Control settings, reference section 8.4 ARM Control in the YRC1000 Instructions Manual (178642-1CD) or section 8.4 ARM Control in the YRC1000micro Instruction Manual (181274-1CD).

If Arm Control is set correctly, with tool data pulled from CAD, and the user is still experiencing PFL alarms or unexpected alarms on an HC robot, reach out to your local YASKAWA representative. There is a possibility that the user’s HC robot was internally set to be wall mounted or inverted through the Robot’s Orientation RO1G Parameters (COORD ORG PRMTR or RO.PRM) which is NOT accessible to the user. Setting the HC robot internally to be wall mounted or inverted has caused issues in the past, with older controller software versions. These bugs/issues have been resolved with newer controller software versions. Depending on user’s controller software version, your local YASKAWA representative might need to change the RO1G parameters back to their default values and use Arm Control to set the correct mount/installation angle of the HC robot.

For YASKAWA representatives, reference “HC Robots Wall Mounted or Inverted – RO1G Parameters” for additional information.