Pick-and-Place Machines, or SMT (surface mount technology) component placement systems, are robotic machines used to place surface mount parts onto circuit boards. The machine is usually used for boards that are more complex and have many parts. For simpler boards, it is faster and easier to solder by hand. The machine utilizes two different suction nozzles (one smaller for smaller parts and the other bigger for bigger parts) to pick up and place your parts on your board.
The model we have at the IMA lab is TM240A, it has 28 tape feeders that can accommodate 28 parts at the same time. Students can only use the machine under supervision of faculty or staff. The use of the machine is taught in the Rapid Prototyping class.
1. Prepping Your Script for the Pick-and-Place
Before schedule time to use the Pick-and-Place machine, you can export a .csv file to copy into the machine with an SD card. To generate the .csv file, you would need to run a .ulp script in Eagle on the board you designed.
First, download the script. You can download the .ulp script here, this script works for both TM220A and TM240A. Copy this file into your Eagle program’s ulp folder. If you are using a Mac, you can find this folder at Application >> EAGLE-7.1.0 >> ulp.
Open your .brd eagle file. Click on the ULP button at the top of the tool bar, find the .ulp script that you copied into the folder and run it.
The script will automatically save a .csv file in the same folder as your Eagle board design files. You should be able to open the file in Excel. The exported file should look something like this:
The data at the bottom section of the .csv file is crucial, it let’s the machine know the positioning of the parts in terms of the x and y positions of their central point, the package of each part in relation to their footprint, and the angel they are turned at on the board. You can double check this file with your board design to see that everything is correct.
NOTE, at the bottom of the chart, there is a section called Stack that is blank, you need to fill in this section manually with the position of materials on your machine, i.e. which part is placed on which real on the machine.
Copy this file onto the SD card for the Pick-and-Place and you are ready to move to the machine. This step is usually more useful for complex boards. For simpler boards, it is more accurate to determine the positioning of each parts manually on the machine. To learn how to do this, please read the Section 3 – Setting Up the Job.
2. Loading the Machine
Video coming soon.
3. Setting Up the Job
Before you turn on the machine, make sure you clear the bed of the machine. This is because when the machine starts up, the nozzle auto-adjusts across the bed. The nozzle moves very fast, so when the machine first turns on or when it’s running a job, make sure there are no obstacles.
The Pick-and-Place has 5 sections in its setup file. This file can be from the .csv file that you generated through running .ulp script, but can also be created in the machine directly. The 5 different sections are:
- Part 1: Origin offset (Section code on .csv file: 65535, 0)
- Part 2: Stack offset (Section code on .csv file: 65535, 1)
- Part 3: Feeding set (Section code on .csv file: 65535, 2)
- Part 4: Panelized board (Section code on .csv file: 65535, 3)
- Part 5: Component part (Section code on .csv file: 1 – 65534) and speed lines
Part 1: Origin offset (65535, 0)
You can readjust the origin of the board in this section. Sometimes, the board you are making is not a square. After you clamp down your board, you need to manually adjust the origin of the offset. You can do this by placing one part using your script, then adjusting it’s position so it matches the footprint, and applying that offset adjustment to the origin.
Part 2: Stack Offset (65535, 1)
This section allows you to manually adjust the pick up point of parts in each stack. The TM240A has 28 stacks that can accommodate for 3 types of different component strip widths for different parts. Technically, if there are multiple components with the same package, you only need to set the stack offsets for the parts where the pick up point needs to change (meaning when the package changes). However, for accuracy purposes, we recommend that you set the stack offset for every stack that is loaded.
Part 3: Feeding Setup (65535, 2)
The feeding setup section allows you to set the feeding rate of each component strip for each stack. Measure the distance between the mid points of components on each strip in mm to set the feeding rate.
Part 4: Panelized Board (65535, 3)
The Pick-n-Place also allows you to work on multiple board in one pass. This section allows you to clamp multiple boards on the X and Y axis to allow a matrix of boards to be done in one pass. Make sure that you do not exceed the Max application PCB size which is 400mm x 360mm.
Part 5: Component Part (1 – 65534) and Speed Lines
This section is the main body of the working file, it sets the mid position of each part and the rotation value. This section can be generated by running a ULP script on your board in Eagle, or manually created on the Pick-n-Place machine by using the laser vision tool. For simpler tools, manual setup is recommended for accuracy.
After you’ve gone through these 5 sections, you are now ready to press the “Go” button and run your job.
Video coming soon.