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    How to build an OMS

    Step by step process of building an OMS
    • Last Update:2026-09-03
    • Version:012
    • Language:en

    Agenda

    • Purchase required hardware
    • Print with 3D printer needed components
    • Assemble components of the OMS
    • Connect electrical components

    Goal

    This how to explains how to build yourself an OMS (Open Manufacturing Station). This machine is able to sort objects by shape using advanced optical inspection algorithms.

     

    Picture 1: a finished Open Manufacturing Station (OMS).

    Video 2: a real machine doing a selection (removing from line cylinders and leaving untouched kubes and triangles).

    Purchase required hardware

    Purchase list

    1. rPLC coupler or build it yourself following tutorial here (1 piece)
    2. Line conveyor (length: 460mm) (1 piece)
    3. A 12VDC push solenoid (18W) (1 piece)
    4. A 5VDC proximity sensor (1 piece)
    5. 20 mm by 20 mm V-slot (3 x 500mm length)
    6. M5 T-slot nuts (20+ pieces)
    7. Bolts and nuts M5x10 mm (20 pieces) and M5x12mm (6 pieces) bolts
    8. Bolts and nuts M3x10mm (4 pieces)
    9. Adjustable legs for 2020 (4 pieces)
    10. 5 Hole Joint Board Plate Corner Angle Bracket (3 pieces)
    11. USB camera (1 piece)
    12. Magnetic stand holder for equipment (1 piece)
    13. A mounting of optical axis fixed support (1 piece, hole diameter; 12 mm)
    14. IP 67 plastic box (minimal dimensions: height: 100mm, width: 240mm, width: 200mm)
    15. An external power converter with output 24VDC and 3.0A
    16. 9-36VDC to 5VDC DIN rail mountable power converter (Model: Meanwell DDR-15G-5, 1 piece)
    17. 9-36VDC to 12VDC DIN rail mountable power converter (Model: ESPE ESPE-HDN1512, 1 piece)
    18. 4 pin Deutsch connector (1 piece)
    19. Few meters of BLACK / RED cables (multi core) with 1 x 0.5mm  for inside electrical connections
    20. Standard center-positive (2.1x5.5mm) male barrel jack (3 pieces)
    21. Standard center-positive (2.1x5.5mm) female barrel jack (1 piece)
    22. DIN rail (500mm)
    23. Rail mount terminal blocks (2 pieces)
    24. Cable Gland (М12х1.5, ф12mm, IP66, Scame, 805.5412 - 3 pieces)
    25. Cable Gland (25mm/M25x1.5, IP66, Scame 805.5425 - 1 piece)
    26. A 10 ml tube of thread locker glue

    Print with 3D printer needed components

    Print primitive shapes used for testing the OMS

    We need to print the basic shapes which will be used to do selections on the real machine. The default PLC program is configured to remove from line ONLY cylinders and leave triangles and rectangles. Thus it is required to print these shapes from respective models

    Print line parts

    We need to print 4 parts which later needs to be mounted on the conveyor as follows

    Recommended 3D printer settings:

    1. Material: PLA (preferred)
    2. Nozzle: 0.4 mm
    3. Infill Density: minimum 50%
    4. Support : Yes
    5. Shell thickness: 0.8 - 1.0 mm

    Assemble components of the machine

    Step 1.1: Cut v-rail

    Please cut two v-rails with a length of 400 mm each.

    Step 1.2: Attach the 4 legs to the v-rails

    Please connect the first leg to the v-rail using two t-nuts and two M5x10mm bolts and screw the M8 leg inside as visible on the picture below. Do again for the other leg. Each leg should be 20 mm from end of the rail.

    At the end you should have following v-rail. Please do make repeat the process one more time.

    Step 1.3: Drill the mount holes of the conveyor belt

    Please drill two mounting holes ("Hole 1" and "Hole 2") for each side of the conveyor belt with 5 mm drill. The 4 holes will be used for mounting the v-rails to.

    Step 1.4: Connect the v-rails to the conveyor belt

    Connect left and side v-rail to conveyor belt using already drilled holes in previous step using a t-nut and M5x10mm bolt. You should see this after it is done.

    Step 1.5: Mount front aligner left to v-rail (left one)

    Please connect with t-nut and M5x10mm bolt the front left aligner to the left v-rail (50 mm from the start of the v-rail) as shown below.

    Step 1.6: Mount front aligner right to v-rail (right one)

    Please connect with t-nut and M5x10mm bolt the front right aligner to the right v-rail (50 mm from the start of the v-rail) as shown below.

    Step 1.7: Mount the proximity sensor stand and proximity sensor to v-rail (right one)

    Please mount first the proximity sensor stand to the v-rail (right) using t-nut and M5x10mm bolt. And only after that connect using the supplied rings to proximity sensor to its stand. The final setup can be seen below:

    The detailed setup picture of proximity sensor stand and proximity sensor can be seen on the following image:

    Step 1.8: Connect solenoid stand with spring and solenoid lever together

    Place the solenoid and tighten it with its nut in the solenoid stand. Then let its cable go through the designated hole just above it. Following image shows it:

    Attach with two bolts the lever and place the spring inside as show in the following picture. After proper testing you can apply a thread locker glue on top of the bolts so that they do not unscrew.

    Step 1.9: Mount already bundled together solenoid stand to v-rail (right one)

    Using t-nuts and two M5x12mm bolts attach to the v-rail (right) the already assembled solenoid stand as shown below.

    A more detailed view from above can be seen below:

    Step 1.10: Drill hole for the camera stand

    Please drill with 6mm drill a whole in the USB camera holder. In the middle of the metal plate.

    Step 1.11: Connect camera  to its stand

    Please connect the camera to the stand using the stand's own bolt into the previously drilled hole. Finally attach the aluminium block which will be used for mounting to the v-rail.

    Step 1.12: Attach camera and its stand to the right v-rail.

    Finally the whole assembly should look like this.

    Step 1.13: Attach the two collect boxes

    Attach the two collect boxes to the left side v-rail using t-shape nuts.

    Step 1.14: Level the OMS machine using legs' blocking nuts

    Please place the machine into a leveled and flat surface. Then using a 13mm wrench adjust the heights of the 4 legs so the conveyor belt is horizontal.

    Prepare plastic box

    Step 2.1: Cut v-rails

    Please cut the 20 x 20 mm v-rail with to length of 250 mm. We need two pieces.

    Step 2.2: Drill holes in the plastic box and attach v-rails to the plastic box

    Please drill two holes with 6 mm drill at back of the plastic box. Using M5x10mm attach the v-rails to the plastic box how can be seen from following images:

    Front

    And back

    Step 2.3: Add connectors for bottom

    Please attach the connectos at bottom of the rails as shown below. These will be used to connect to the structure of the conveyor belt.

    And view from the top part:

    Step 2.4: Drill holes for incoming power cable and outgoing cables

    Please download and print this drilling template on the right side of the box using proper radios!

    Then attach accordingly cable gland connectors like so:

    Step 2.5: Attach DIN rails to back (inside) plastic box

    Please attach as follows the two DIN rails (each 180 mm long)

    Connect electrical components inside the plastic box

    The general electric schema of OMS.

    Step 3.1: Install rail terminal blocks and connect 24VDC power source to them

    Step 3.2: Install and power up 24VDC -> 5VDC power converter

    Please use jumper cables with 10cm of length and power up accordingly from terminal rail blocks. Mind the polarity and make sure to use input connectors!


    Step 3.3: Connect a barrel jack to output of 5VDC power converter

    Using 25cm cables please connect output of 5VDC to a barrel jack which will be used to power up LIME2 board inside rPLC coupler. 

    Step 3.4: Power up 12DV converter

    Please install sh shown on picture 12VDC converter and power it from rail termninal blocks (left side). Please use cables with length of 25cm. Please pay attention to connect to input of the converter and mind the polarity

     

    Step 3.5: Connect a barrel jack to output of 12VDC power converter

    Using 17cm cables please connect output of 12VDC to a barrel jack which will be used to power up MOD-IO  board inside rPLC coupler. 

    Step 3.6: Mount rPLC coupler on the left DIN rail

    Please mount the rPLC coupler on the left DIN rail but first make sure to remove its top cover.

     

    Step 3.7: Wire circuits for RELAY1 and RELAY2

    Please using the schema wire the circuits using power sources as follows:

    • REALY1 -> 24VDC (from terminal left side)
    • RELAY2 -> 12VDC (from 12VDC power converter)

    Please use following cable lengths:

    • RED: 25cm and 75cm (to be terminated through respective RELAY)
    • BLACK: 100 cm

    Please leave the other end of the cable terminated as both REALY1 and RELAY2 circuits will be adjusted to a 4 pin Deutsch connector later.

     

    Step 3.9: Wire circuits of proximity sensor to digital IN1 (on MOD-IO board)

    Please connect as follow:

    • BLUE cable of proximity sensor connected 5V+ (on respective power converter) and to IN1 bottom connector
    • BLACK cable of proximity sensor to the other IN1 connector
    • BROWN to 5V- (on respective power converter)

    Once you  are ready with cabling please move them outside (through glides) the plastic box as show in picture below.

    Step 3.10: Place top cover or rPLC coupler using designated screws

     

    Step 3.11: Connect all power, network and camera cables

    Please connect

    • LAN cable
    • USB camera cable
    • 5VDC barrel jack (next to USB camera cable)
    • 12VDC barrel jack (right rPLC side)

    Step 3.12: Place plastic box cover

    Please crew plastic cover.

    Step 3.13: Add Deutsch connector

    Please add a Deutsch 4 pin connector which connects:

    • REALY1 (24VDC) to conveyor belt motor
    • RELAY2 (12VDC) to solenoid

    Please mind polarity. Please add connector female part to the OMS and male part to the respective belt motor / solenoid.

     

    Step 3.14: Mount plastic box on conveyor belt and connect cables

    Please mount the plastic box on the conveyor belt.

    Step 3.15: Mount camera stand and position the camera

    Please mount the camera onto its stand and make sure that it is positioned properly.

    Step 3.16: Mount proximity sensor

    Attached the proximity sensor to its stand.

     

    Your OMS is ready!