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*** Quick Update 6/27/2022 *** This is a great quick overview from Mitsubishi ----------------------------------------------------------------------------------------------------------------------------- Mitsubishi CC-Link networks have grown substantially over the past decade and it’s no wonder that there is some confusion on the various versions. This blog is to give a quick overview and hopefully clear up some of what can be rather muddy waters. Let’s start with what CC-Link is: CC-Link is a FAMILY of protocols created and maintained by the CC-Link Partner Association (https://www.cc-link.org/) Very much like other industrial communication protocols, it is used to communicate between industrial devices. CC-Link is also an open standard meaning that it is not controlled by Mitsubishi, but instead the CC-Link Partner Association and many vendors participate in this Association to promote a standard that works throughout the world. There are over 250 companies participating as members of the CCLPA in all sectors of Automation and Industry. The number of products which communicate using one of the various versions of CC-Link is increasing steadily. In 2005 there were 740 products on the market and in 2019 there were almost 2100, so a 3 fold expansion and the product offerings continue to expand. So why is there confusion in the market over CC-Link products? I believe a lot of it comes down to nomenclature. Just like Modbus had Modbus RTU, Modbus ASCII, and Modbus TCP, CC-Link comes in many versions: • CC-Link • CC-Link/LT • CC-Link Safety • CC-Link IE Field Network Basic • CC-Link IE Field • CC-Link IE Control • CC-Link IE Safety • CC-Link IE TSN • And SLMP (Seamless Messaging Protocol) Before CC-Link IE TSN came around the overview looked like this: It’s also important to understand what is involved in the various protocols in regards to hardware and software which can be explained with this graphic, again this is prior to TSN. It can be somewhat easier to understand if we look at this from a historic perspective. Starting with SLMP. SLMP is simply the messaging protocol used. It is the data packet structure that goes back and forth between the devices. Then we use RS-485 hardware as the underlying transport for classic CC-Link. Stepping up in time the CLPA created CC-Link IE Field and CC-Link IE Control. CC-Link IE Control is Ethernet based on a Fiber Optic network for high speed token based data transfer and it is usually used for machine-to-machine communication when a lot of data needs to be sent and full determinism is critical. CC-Link IE Field on the other hand is based on standard copper Ethernet and can use ring, line or star networks. Both CC-Link IE Control and CC-Link IE Field need to exist as their own stand-alone network. If you look at the model above you can see that they exist right on top of the Ethernet hardware, they are very low-level protocols and do not rely on the IP Stack and TCP/UDP protocols. Because of this, these networks (CC-Link IE Field and CC-Link IE Control) must be kept on their own hardware and separate from classic business networks. This is where CC-Link IE Field Network Basic comes into play. CC-Link IE Field Network Basic is a fast, Ethernet based protocol that rests on top of the TCP/UDP stack. This means that CC-Link IE Field Network Basic can coexist with other standard Ethernet traffic and you can connect it to standard business class Ethernet switches along with your normal network traffic. The downside of this, is that CC-Link IE Field Network Basic is non-deterministic and the time from packet to packet can change depending on network traffic. This finally brings us to CC-Link IE TSN. TSN stands for Time Sensitive Network. Without getting too deep into the technology, the TSN network allows high speed deterministic networking that has the potential to be even faster than CC-Link IE Field or CC-Link IE Control. It also will be capable of existing on networks with other traffic, as long as the switching hardware that is used is designed to accommodate it. As a general rule of thumb, here are the details and uses of each network (and like all rules-of-thumb, there are exceptions!). CC-Link (including CC-Link, CC-Link/LT and CC-Link Safety) - Serial based network for device level control - Works for small networks of devices with speeds up to 10Mbps - Great low cost option for sensor networks, VFDs, and actuators like IAI Robocylinders - not intended for coordinated motion control or large volumes of data CC-Link IE Field Basic - Ethernet based network for machine level communication using CAT 5E or CAT 6 cabling - can co-exist on standard business type networks using standard business class switches and hardware - intended for device level control such as sensors, valve banks, VFDs, etc - cannot perform coordinated motion control, and is non-deterministic CC-Link IE Field - Ethernet based network for machine level communication using CAT 5E or CAT 6 cabling - cannot co-exist on standard business type networks, it must be separated to a network only running CC-Link IE Field devices, uses a token based network - intended for high-speed, deterministic communication and is often used for servo motion, industrial Robot communication, and deterministic remote I/O CC-Link IE Control - Ethernet based network for inter-machine level communication using fiber optic cabling - Intended for larger volumes of data and a high speed network for synchronizing data between large systems such as different manufacturing cells on the same manufacturing floor CC-Link IE TSN - The newest network, this network works on standard copper Ethernet and should use CAT 6 cabling - provides real-time communication between devices on a deterministic network - uses a time sharing technology as opposed to a token based system - allows for even higher-speed coordinated motion control than CC-Link IE Field - can co-exist with standard business level traffic on the same network if properly enabled Ethernet switches are used - devices such as VFDs, servo motors, and high speed inspection cameras can all co-exist on the same network and achieve communication speeds previously not attainable As the main take-away, I hope you have been able to pick up the main differences between these various networks. Each is it’s own unique system and for the most part there are no converters or ways for the different networks to communicate with each other unless it’s done through a PLC or other specialized hardware. So choosing the correct hardware in terms of a control platform and devices can be somewhat confusing, but hopefully you now understand the differences. And if you need any help in choosing a network or components, please reach out to Gibson Engineering as we are here to support you in navigating these various technologies. For more reading: CC-Link IE and CC-Link IE TSN details here: https://www.mitsubishielectric.com/fa/products/cnt/plcnet/pmerit/concept/index.html

A very common question is "what software do I need to purchase to program my PLC?". Luckily with Mitsubishi, the answer is simple. GX Works3. As of the release of the iQ-F (FX5) and iQ-R series PLCs, Mitsubishi released their newest programming platform, GX Works3. And the best part is, when you buy it, you get the two previous programming platforms with it. You also get GX Works2 and GX Developer, all for one price and the price is the same as GX Works2 was, so you are paying the same as you used to and you are getting 3 packages. So which package do you need for which PLC? Use the following chart: *** there is a compatibility mode whereby GX Works 3 will open Q or L or FX3 series projects that is not noted in this chart

Did you know that Mitsubishi FR-A800, FR-E800 and FR-F800 series Variable Frequency Drives (VFDs) include built-in Programmable Logic Controller (PLC) functionality? That’s right, the VFDs/Inverters that you are used to using to drive your 3-phase motors have a built-in PLC that can be enabled to do logic control without an external device. Not only this, but you can add extra input and outputs via add-on cards to expand the functionality. Let’s look at a simple example – the E800 VFD This new inverter from Mitsubishi comes in two different styles, the classic serial connection and Ethernet connection. And both have a MELSEC 2K Step PLC included. This might allow you to reduce internal components and save panel space, eliminating wiring time, and reducing system setup times. Not only could you have a system comprised of a single VFD providing both functions of a PLC and Inverter, but you can use inverter-to-inverter communication. The inverter-to-inverter link function enables communication between multiple inverters connected by Ethernet in a small-scale system by using the I/O devices and special registers of the PLC function. You can also connect a GOT2000 series operator interface panel to the VFD to interact with the system and change various parameters in your PLC program. Using expansion modules you can add more inputs and outputs to your inverter including not only digital inputs and outputs but analog as well. And it provides all the familiar programming languages that PLC programs are used to using, including Function Block Diagram, Ladder and on the E800 Structured Text. All of this is done using Mitsubishi’s FR-Configurator 2 software and the FR Configurator 2 Developer programming environment. So the next time you have an application such as a conveyor application or pump application that requires more than just a motor drive you might consider the Mitsubishi family of inverters with built-in PLC.

As yet another example of the amazing flexibility and power that Mitsubishi’s iQ-F Controller, Mitsubishi has now added Sequential Function Chart programming to the FX5U and FX5UC compact, cost effective PLCs. If you have been a PLC programmer for a long time you have probably programmed in ladder logic, and most likely Function Block Diagram languages (FBD) which has also been called Structured Ladder programming. You might have even used Structured text (ST) programming. But have you ever tried SFC? If you have a project where the machine acts very sequentially, SFC can’t be beat for making troubleshooting the sequence easier and faster. Let’s explore all of the available languages in the FX5U and FX5UC PLCs. The first is Ladder programming and it is the classic language for PLC programming which comes from classic relay logic. Ladder Logic is very easy to read for standard input and output logic if all you need are inputs, outputs, timers and counters. Once you go beyond simple logic, Ladder programming can start to look and feel kind of clunky. As you can see below, once we start trying to add Function Blocks into ladder, the classic clean look and feel starts to get broken up. The simple Set/Reset block really feels out of place. That’s where Function Block Diagram (FBD) programming starts to show it’s power. It is much cleaner and easier to read when we start using larger function blocks. It also lends itself well to Object Oriented Programming techniques. We also have Structured Text programming available to us. For those who have done extensive PC programming, a text based language may feel much more comfortable, but for PLC programmers there are still significant advantages to this language. For performing complex math or string manipulation, Structured Text (ST) language makes for a very clean, compact, easy to read language. So with having 3 languages already, why would we need or want a fourth? First, let’s examine what SFC programming is. The name gives it away: Sequential Function Chart. SFC is represented as a flow chart format with Blocks, Actions, and Decisions (transitions). An SFC program starts at an initial step, executes the next step every time the relevant transition becomes TRUE, and ends a series of operations at an end step. 1. When starting a block, the initial step (1) is activated first and then the action (2) is executed. After execution of the action (2), the program checks whether the next transition (3) has become TRUE. 2. The program executes only the action (2) until the transition (3) becomes TRUE. When the transition (3) becomes TRUE, the program ends the action (2), deactivates the initial step (1), and activates the next normal step (4). 3. After execution of the action of the normal step (4), the program checks whether the next transition has become TRUE. If the next transition does not become TRUE, the program repeats the execution of the action of the normal step (4). 4. When the transition becomes TRUE, the program ends the action, deactivates the step (4), and activates the next step (5). 5. Every time the transition becomes TRUE, the program activates the next step and ends the block when it finally activates the end step (6). So where would I use SFC and why? If you’ve ever written ladder and used STL (Step Ladder) instructions or if you’ve ever written your own State Machine logic, then you’ve basically written SFC programs without knowing it. However, SFC has some advantages over STL and State Machine Logic in plain ladder. With SFC, only the ACTIVE block is scanned. This means that the CPU can scan much faster and is much more efficient. Not only is your scan time reduced (often by very significant amounts), when monitoring SFC, you can see which step or steps are active very quickly and easily and jump right to a very small section of code to see what is going on. In previous generations of PLCs, the logic inside SFC had to be written in Ladder programming. Now with the iQ-R and iQ-F PLCs, the code resides in an Action. Each Step can have up to 4 Actions tied to it, and each Action can be written in any of the standard three languages. With the latest release of GX Works3 Programming software (Version 1.070Y) we now have SFC available to us on the FX5U and FX5UC series PLCs. If you have a PLC with serial number 1.7X or later, you can update the firmware to version 1.220 and take advantage of this powerful language. I hope this brief introduction into SFC has piqued your interest. Now go write some code!

Okay - this is tough because it depends on how you are connecting on your PC side and how you are connecting on your PLC side, and new products get added and things change, but here's a general summary. Generally speaking this can be simplified: If you are on a PLC from the last 5-10 years (it's 2020 now) then mini-USB is probably available on the PLC, if mini-USB is not available, then Ethernet is with the exception of the FX3U and the Alpha. So this includes FX3S, FX3G, L Series, Q Series and R Series released in the last 10 years If you are working with an FX1S, FX1N, FX2N, FX3x PLC the front port is an 8 pin mini-DIN RS-422 cable and you can use the FX-USB-AW cable If you are working with an older FX PLC with the 25 pin connector, get the SC-09 cable and get a USB to Serial adapter like the Keyspan/Tripplite USA-19HS If you are working on a Q PLC that is slightly older it may have a mini-DIN connector on it, this is a 6 pin mini-DIN and is not the same as the mini-DIN on the FX series, it is RS-232. For this you need the SC-Q cable with a USB to Serial adapter, or the GT10-RS2TUSB-5S and a mini-USB cable As an experienced Mitsubishi programmer, I keep 5 cables in my bag and this setup covers me for 99% of what I need: Classic SC-09 Cable to program either new or old FX series and some old A series PLCs Keyspan/Tripplite USA-19HS serial to USB converter Mini-USB Cable with Ferrite core like the MR-J3USBCBL3M or GT09-C30USB-5P GT10-RS2TUSB-5S converter to connect to old Q series and some HMIs with the round RS232 connector A good quality Ethernet cable around 10' long. If I didn't have to worry about the old FX and A series, then the FX-USB-AW would replace cables 1, 2 and 3 in this list! Below is a table that shows what cable you should need for what PLC. Family Model Connection Type PC Side Connection Type PLC Side Cable # Alpha Alpha2 RS-232 (9 Pin Serial) Front Panel Connection AL-232CAB FX FX-XXX RS-232 (9 Pin Serial) RS-422 (DB25) SC09 FX FX1N-XXX RS-232 (9 Pin Serial) RS-422 (mini-Din) SC09 FX FX1N-XXX USB RS-422 (mini-Din) FX-USB-AW FX FX1S-XXX RS-232 (9 Pin Serial) RS-422 (mini-Din) SC09 FX FX1S-XXX USB RS-422 (mini-Din) FX-USB-AW FX FX2NC-XXX RS-232 (9 Pin Serial) RS-422 (mini-Din) SC09 FX FX2NC-XXX USB RS-422 (mini-Din) FX-USB-AW FX FX2N-XXX RS-232 (9 Pin Serial) RS-422 (mini-Din) SC09 FX FX2N-XXX USB RS-422 (mini-Din) FX-USB-AW FX FX3G-XXX RS-232 (9 Pin Serial) RS-422 (mini-Din) SC09 FX FX3G-XXX USB RS-422 (mini-Din) FX-USB-AW FX FX3G-XXX USB mini-USB-B MR-J3USBCBL3M FX FX3S-XXX RS-232 (9 Pin Serial) RS-422 (mini-Din) SC09 FX FX3S-XXX USB RS-422 (mini-Din) FX-USB-AW FX FX3S-XXX USB mini-USB-B MR-J3USBCBL3M FX FX3UC-XXX RS-232 (9 Pin Serial) RS-422 (mini-Din) SC09 FX FX3UC-XXX USB RS-422 (mini-Din) FX-USB-AW FX FX3U-USB-BD USB FX3U-USB-BD MR-J3USBCBL3M FX FX3U-XXX RS-232 (9 Pin Serial) RS-422 (mini-Din) SC09 FX FX3U-XXX USB RS-422 (mini-Din) FX-USB-AW FX5 (iQ-F) FX5U-XXX Ethernet (wired) Ethernet (wired) FX5 (iQ-F) FX5UC-XXX Ethernet (wired) Ethernet (wired) FX5 (iQ-F) FX5UJ-XXX Ethernet (wired) Ethernet (wired) FX5 (iQ-F) FX5UJ-XXX USB mini-USB-B MR-J3USBCBL3M L L02 Ethernet (wired) Ethernet (wired) L L02 USB mini-USB-B MR-J3USBCBL3M L L06 Ethernet (wired) Ethernet (wired) L L06 USB mini-USB-B MR-J3USBCBL3M L L26 Ethernet (wired) Ethernet (wired) L L26 USB mini-USB-B MR-J3USBCBL3M QCPU Q00U USB mini-USB-B MR-J3USBCBL3M QCPU Q00U RS-232 (9 Pin Serial) RS-232 (mini-DIN) SC-Q QCPU Q00UDE Ethernet (wired) Ethernet (wired) QCPU Q00UJ USB mini-USB-B MR-J3USBCBL3M QCPU Q01 RS-232 (9 Pin Serial) RS-232 (mini-DIN) SC-Q QCPU Q02 RS-232 (9 Pin Serial) RS-232 (mini-DIN) SC-Q QCPU Q02H RS-232 (9 Pin Serial) RS-232 (mini-DIN) SC-Q QCPU Q02U USB mini-USB-B MR-J3USBCBL3M QCPU Q02U RS-232 (9 Pin Serial) RS-232 (mini-DIN) SC-Q QCPU Q02UDE Ethernet (wired) Ethernet (wired) QCPU Q03U USB mini-USB-B MR-J3USBCBL3M QCPU Q03U RS-232 (9 Pin Serial) RS-232 (mini-DIN) SC-Q QCPU Q03UDE Ethernet (wired) Ethernet (wired) QCPU Q04U USB mini-USB-B MR-J3USBCBL3M QCPU Q04U RS-232 (9 Pin Serial) RS-232 (mini-DIN) QCPU Q04UDE Ethernet (wired) Ethernet (wired) QCPU Q06H RS-232 (9 Pin Serial) RS-232 (mini-DIN) SC-Q QCPU Q06U USB mini-USB-B MR-J3USBCBL3M QCPU Q06U RS-232 (9 Pin Serial) RS-232 (mini-DIN) SC-Q QCPU Q06UDE Ethernet (wired) Ethernet (wired) QCPU Q0OJ RS-232 (9 Pin Serial) RS-232 (mini-DIN) SC-Q QCPU Q100U USB mini-USB-B MR-J3USBCBL3M QCPU Q100U RS-232 (9 Pin Serial) RS-232 (mini-DIN) SC-Q QCPU Q100UDE Ethernet (wired) Ethernet (wired) QCPU Q10U USB mini-USB-B MR-J3USBCBL3M QCPU Q10U RS-232 (9 Pin Serial) RS-232 (mini-DIN) SC-Q QCPU Q10UDE Ethernet (wired) Ethernet (wired) QCPU Q12H RS-232 (9 Pin Serial) RS-232 (mini-DIN) SC-Q QCPU Q12PH RS-232 (9 Pin Serial) RS-232 (mini-DIN) SC-Q QCPU Q13U USB mini-USB-B MR-J3USBCBL3M QCPU Q13U RS-232 (9 Pin Serial) RS-232 (mini-DIN) SC-Q QCPU Q13UDE Ethernet (wired) Ethernet (wired) QCPU Q20U USB mini-USB-B MR-J3USBCBL3M QCPU Q20U RS-232 (9 Pin Serial) RS-232 (mini-DIN) SC-Q QCPU Q20UDE Ethernet (wired) Ethernet (wired) QCPU Q25H RS-232 (9 Pin Serial) RS-232 (mini-DIN) SC-Q QCPU Q25PH RS-232 (9 Pin Serial) RS-232 (mini-DIN) SC-Q QCPU Q26U USB mini-USB-B MR-J3USBCBL3M QCPU Q26U RS-232 (9 Pin Serial) RS-232 (mini-DIN) SC-Q QCPU Q26UDE Ethernet (wired) Ethernet (wired) QCPU Q50U USB mini-USB-B MR-J3USBCBL3M QCPU Q50U RS-232 (9 Pin Serial) RS-232 (mini-DIN) SC-Q QCPU Q50UDE Ethernet (wired) Ethernet (wired) QCPU QO1U USB mini-USB-B MR-J3USBCBL3M QCPU QO1U RS-232 (9 Pin Serial) RS-232 (mini-DIN) SC-Q QCPU QO1UDE Ethernet (wired) Ethernet (wired) AnSH AnSH RS232 RS422 SC09 Qmotion Q172D USB mini-USB-B MR-J3USBCBL3M Qmotion Q172D RS-232 (9 Pin Serial) RS-232 (mini-DIN) SC-Q Qmotion Q170M RS-232 (9 Pin Serial) RS-232 (mini-DIN) SC-Q Qmotion Q170M USB mini-USB-B MR-J3USBCBL3M Qmotion MRMQ100 Ethernet (wired) Ethernet (wired) Qmotion Q170M Ethernet (wired) Ethernet (wired) RCPU R00CPU USB mini-USB-B MR-J3USBCBL3M RCPU R00CPU Ethernet (wired) Ethernet (wired) RCPU R01CPU USB mini-USB-B MR-J3USBCBL3M RCPU R01CPU Ethernet (wired) Ethernet (wired) RCPU R02CPU USB mini-USB-B MR-J3USBCBL3M RCPU R02CPU Ethernet (wired) Ethernet (wired) RCPU R04CPU USB mini-USB-B MR-J3USBCBL3M RCPU R04CPU Ethernet (wired) Ethernet (wired) RCPU R08CPU USB mini-USB-B MR-J3USBCBL3M RCPU R08CPU Ethernet (wired) Ethernet (wired) RCPU R16CPU USB mini-USB-B MR-J3USBCBL3M RCPU R16CPU Ethernet (wired) Ethernet (wired) RCPU R32CPU USB mini-USB-B MR-J3USBCBL3M RCPU R32CPU Ethernet (wired) Ethernet (wired) RCPU R120CPU USB mini-USB-B MR-J3USBCBL3M RCPU R120CPU Ethernet (wired) Ethernet (wired) RCPU R04ENCPU USB mini-USB-B MR-J3USBCBL3M RCPU R04ENCPU Ethernet (wired) Ethernet (wired) RCPU R08ENCPU USB mini-USB-B MR-J3USBCBL3M RCPU R08ENCPU Ethernet (wired) Ethernet (wired) RCPU R16ENCPU USB mini-USB-B MR-J3USBCBL3M RCPU R16ENCPU Ethernet (wired) Ethernet (wired) RCPU R32ENCPU USB mini-USB-B MR-J3USBCBL3M RCPU R32ENCPU Ethernet (wired) Ethernet (wired) RCPU R120ENCPU USB mini-USB-B MR-J3USBCBL3M RCPU R120ENCPU Ethernet (wired) Ethernet (wired)

While this doesn't cover absolutely everything this is a good start at a listing of the most common batteries needed for Mitsubishi PLCs.

There is always debate about when Mitsubishi’s new servo amplifiers such as MR-J4 and MR-JE CC-Link IE Field Basic should be used? To understand this you need to step back and understand what functionality they bring to the wealth of product offering Mitsubishi has in their toolbox. The biggest advantage is that there is no need for extra motion control modules. It is based on CC-link IE Field protocol which in a full functionality mode is a Gigabit based deterministic protocol over Ethernet. However, IE Field Basic is not deterministic so speed might be a consideration when deciding if this is right for your application. A CC-Link IE Field Basic axis can only be used as a stand-alone single axis, so there is no way to synchronize axes together on this network. The best applications for these servo amplifiers are when single axis point to point motion is the only requirement. If you are going to use Homing, Absolute or Incremental moves, Velocity or Torque control as a single axis then this is your amplifier. If all you need is simple single axis servo functionality, from one or multiple servos, these amplifiers can be tied together over the built in Ethernet available on most Mitsubishi PLCs. This functionality simplifies your overall system architecture, reduces costs by reducing any additional hardware, and reducing deployment time with available PLC function blocks. There are many quick startup guides which can be found on Mitsubishi's website and here on Gibson Engineering’s Knowledge Base. If you have questions or would like to learn more please reach out to us at Gibson Engineering. Quick Start Guide for MR-J4-GF CC-link IE field Basic on GX-Works3 for IQ-F(FX5)) Quick Start Guide for MR-J4-GF CC-link IE field Basic on GX-Works3 for IQ-R) Quick Start Guide MR-J4-GF CC-Link IE Field Basic Servo Amplifier on the GX Works2 for Q PLC ) Quick Start Guide- How to use the PLCopen FBs for MR-JE-C CC-Link IE Field Basic)(Links of FBs: 1: MR-JE-C PLCopen Library in iQ-R PLC 2: MR-JE-C PLCopen Library in Q PLC 3: MR-JE-C PLCopen Library in iQ-F PLC)

Let’s say you are trying to implement a pick and place application with your robot. Industrial robots are amazing in terms of going to the place they were told to go. But what if that place we told them to go changes constantly and we don’t know where the part is going to be next time around. That’s when we use machine vision’s help to guide our robot to the right pick location. The general idea is that a vision system needs to be looking at the potential pick locations, and tell the robot where to go and pick up the next part. I’m sure a lot of you would agree that communication is the key to success. That is no different in this case. If two people are speaking different languages that conversation is not going to work great. In digital cameras, there is a sensor that collects the light from the outside world and converts it into electricity. The sensor has “points” (or you can call it a grid) on it that are called pixels. The images we obtain from the camera are represented in these pixels. Robots on the other hand, have coordinate systems. And they usually get represented in meters or millimeters. Two different languages... The whole magic is to be able to know where the camera is located relative to the robot end of arm tooling. Camera can either be mounted at: The end of arm tooling A stationary location If the camera is mounted at the end of arm, we need to know the location of the camera relative to our gripper. At this stage, we only need to know the relative location in terms of two dimensions. The third dimension, we usually can control. For example, if the camera is mounted 3 inches in X and 1.5 inches in Y away from the end of arm tooling, and our part is in the middle of camera’s field of view, the robot needs to move -3 inches in X and -1.5 inches in Y (on its end of arm tooling’s coordinate system) to be able to grab the part. Wait a second, how about the Z? In the robot program, I always have a set location to take my picture before the pick so I know how far the robot end of arm tool is relative to my parts in terms of Z. But what if the part is not in the center of the field of view of the camera, the camera needs to report the part’s location somehow to the robot right? Yes, and that’s when the calibration comes into play. Basic idea is to calibrate the camera’s pixel readings into robot coordinates. Since most of the time, the robots work in real world coordinates (mm or m), you can use the built in calibration function on your camera software if it has one. These routines usually require some type of a grid with known size squares or circles so the camera can do math to convert it’s pixels to real world coordinates. I usually don’t do that. I would have to make sure my axes are aligned perfectly and would have to take lens distortion into consideration somehow. I make a randomly marked paper or plate (see the plate below with holes in it) and use that as the calibration grid. Here are some simple steps and tips to get the calibration process working; Jog the robot to the location where the picture is going to be taken and take a picture. Make sure all the markers on the plate are visible on the image and the top of the plate is the same distance away from the camera as the top of the part you are eventually going to pick up. Note all the locations of the markers in pixels from the camera software. You will need to implement some tools in the vision system to be able to get location data from these markers. Jog the robot to each of these markers and note down the locations in robot coordinates. All you need to do now is to match the pixel location of the marker and the robot location of the marker and do math! Cognex Insight cameras have a built vision tool called N-Point calibration to do this very easily. You select the markers on the plate and write down the corresponding robot coordinate in a table. The software takes care of the rest and your location tools (like PatMax) will report back in robot coordinates now. Almost the same process when the camera is mounted on a stationary location. You just need to know where the camera is located relative to the arm. Only other thing to be careful about now is that the camera needs to be farther away from the pick area so that the robot arm can swing in and grab the part without hitting the camera. Understanding the basics, it’s not so scary to do a vision guided pick and place anymore. Does it still scare you? If so leave a comment below or reach out to us at https://www.gibsonengineering.com/. Disclaimer: This blog post is valid for using 2D cameras for doing a pick and place of the same type of part. Depending on the parts and the hardware used, some additional steps might need to be taken.