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How-to-Guide: Using the Vention Linear Motion URCap

Francois Giguere Head of Automation / Oct 24th, 2018

Table of Contents

Introduction

The Vention MachineMotion controller supports direct communication with the Universal Robots controllers. This integration makes it simple and cost-effective to create systems that unite UR six-axis robot arms with Vention linear axes. Using an intuitive URCap application, a Vention linear axis can be controlled directly from the UR teach pendant.

Figure 1: UR10 Mounted on a Vention 7th Axis Range Extender

This article will explain the setup process to control a Vention linear axis directly from the UR teach pendant using the Vention Linear Motion URCap.

Connecting the Electrical Hardware

The MachineMotion controller ships with pre-labeled motors and sensors. Depending on the application, the system can have up to six (6) motors (three [3] independent axes) and nine (9) sensors. Pre-labeled motors and sensors match their corresponding connectors on the controller front panel (see Figure 2).

Figure 2: MachineMotion Labelled Connectors

As an example, the system diagram below represents a singe-axis system that utilizes two end-of-travel sensors and one motor.

Figure 3: 1-Axis MachineMotion Example System

Network Configuration

Communication between the UR controller and MachineMotion uses Ethernet. The UR controller has an Ethernet port available on its bottom panel, and the MachineMotion controller has one on its front panel. The two units shall be connected using an Ethernet cable. This configuration is peer-to-peer. In order for the Ethernet communication to function, both devices need to be properly configured.

Figure 4: 1-Axis MachineMotion Example System with Ethernet Peer-to-Peer Connection to UR Controller

In this system, the UR controller is the master (client). It runs the application level program and sends commands and queries to the MachineMotion controller (server).

MachineMotion

  1. Connect MachineMotion to a 120Vac power source via the power cable and POWER connector.
  2. Connect a computer that has Google Chrome installed to the USB cable of MachineMotion.
  3. Power on the system using the green rocker switch.
  4. Wait ~ 90 seconds for the system to complete its booting sequence.
  5. Using Google Chrome, browse to 192.168.7.2:8888/_apps/_appControlCenter.html
  6. A window (see Figure 5) will be displayed.
  7. The field highlighted in red in Figure 5 will be edited to set the IP address of the MachineMotion controller. The default suggested IP for the MachineMotion controller is 192.168.0.2 and this value will be utilized throughout the rest of this document as the MachineMotion controller IP address.
  8. Once the field is modified with the proper IP address, simply click the green "update" button beside it.
  9. The new IP will become visible in the "Live IP" field just above.

Figure 5: Vention MachineApp: ControlCenter

MachineMotion IP Addresses

The MachineMotion controller has two (2) different network interfaces: ETHERNET and USB. These two (2) interfaces are distinct, and consequently can be configured differently. They have different IP addresses. The table below highlights the differences between the two interfaces:

Physical Port IP Address Configurable Default Netmask Default Gateway
ETHERNET [default = 192.168.0.2] YES 255.255.255.0 192.168.0.1
USB [192.168.7.2] NO 255.255.255.0 192.168.7.1

MachineMotion IP Ports

The MachineMotion controller serves different ports. The regular Vention Apps can be accessed on port "8888" and communication for the UR Controller is done via port "9999".

UR Controller

  1. On the teach pendant home screen, click on Setup Robot

Figure 6: Polyscope Home Screen

  1. From the "Setup Robot" screen, click on Network

Figure 7: Setup Robot Screen

  1. Enter the parameters as seen in Figure 8. Note that 192.168.0.3 is used here as the UR controller IP address and that 192.168.0.2 is used as the MachineMotion controller IP address. Any address in the 192.168.0.xxx subnetwork is acceptable. The other parameters should be configured as seen in Figure 8. Click on Apply.

Figure 8: Network Parameters Setup

  1. The network status line should display Network is connected after a few seconds. The network setup is completed.

Installing the Vention Linear Motion URCap

The teach pendant has a USB port that can be used to load .urcap files. For more details on how to get Vention's URCap package, please contact a sales representative at sales@vention.io

  1. On the teach pendant home screen, click on Setup Robot

Figure 9: Polyscope Home Screen

  1. From the Setup Robot screen, click on URCaps

Figure 10: Setup Robot Screen

  1. Click on the + button at the bottom of the screen to add a new URCap to the Teach Pendant

Figure 11: Add URCap File

  1. Browse to the Vention .urcap file and select it

Figure 12: Add URCap File

  1. Restart the controller upon successful setup

Figure 13: Successful setup, restart the controller

How to Use the Vention Linear Motion URCap

Installation Screen

In order for the the UR controller to communicate with the MachineMotion controller, an installation must be completed in the Polyscope environment.

Figure 14: Vention's URCap Installation Screen

  • Upper Window
    This window is used to define a MachineMotion controller instance. Note that multi-controller systems can be created by adding more than one controller.

    • Controller Name: Name given to the MachineMotion controller.
    • IP Address: IP address of the MachineMotion controller. In Figure 14, IP address 192.168.0.2 is utilized for the MachineMotion controller.
  • Lower Window
    This section is utilized to define axes of motion. For example, this system has a single axis on port one (1) of the controller, hence the one (1) under the Axis Index setting.

    • Axis Index: Indicates which port the axis is connected to on the MachineMotion controller.
    • Gain: Mechanical gain of the mechanical system in mm per motor turn.
    • Micro-stepping: These settings must match the micro-stepping setup of the controller (8 is default).
    • Speed: Default displacement speed in mm/s of the axis if none is specified in the program.
    • Acceleration: Default displacement acceleration in mm/s2 of the axis if none is specified in the program.
  • Important Note on Homing
    When the installation of the Vention URCap completes, all axes will automatically home to their starting position. The installation runs everytime a robot program is started. The homing process executes as follows:

    1. The axis will slowly move in the negative direction.
    2. Endstop sensors will the triggered.
    3. Movement will stop and the home location is now calibrated.
  • Important Note on Active Installation
    When controlling the MachineMotion controller via the teach pendant and it's URCap, the appropriate installation must be saved and ran upon start-up of the robot program. If the MachineMotion controller is removed from the system, it is important to replace the installation file for one that does not contain MachineMotion specific commands. Not doing so could cause the robot program to hang on start-up.

Control Screen

When creating a robot program, the Vention URCap can be found in the URCaps tab as shown in the image below:

Figure 15: Vention URCap in the program structure editor

Adding a 7th axis robot command to the robot program:

Figure 16: Vention URCap control screen

This screen is where commands can be issued to the MachineMotion controller.

  • Position
    This is the position in millimeters where the linear axis will move. Unless the relative check box is activated, all positions are with respect to the home location (0 mm). For example, a position of 200 mm will result in the linear axis moving 200 mm away from the home location. If the linear axis is already positioned at 200 mm on the linear axis, then it would simply remain in place and not move.

  • Relative Checkbox
    If the relative checkbox is activated, position commands are relative to the current position of the linear axis. For example, a position of 200 mm will result in the linear axis moving 200 mm away from its current location. If the linear axis is already positioned at 200 mm on the linear axis, then it would move 200 mm away in the positive direction. Its final absolute position would be 400 mm.

  • Speed
    Coasting speed of the linear axis in millimeter per second. The system utilizes a trapezoidal speed profile which contains an acceleration period, a coasting period and a final deceleration period. The speed increases linearly until coasting speed is reached, and finally decreases linearly until speed reaches zero. The Speed setting configures the coasting speed.

  • Acceleration
    Acceleration of the linear axis in millimeters / second2. This parameter controls the acceleration and deceleration of the trapezoidal speed profile. The acceleration and deceleration are equal.

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