DM_Gripper - Assembly Guide
DM_Gripper is designed with an assembly/disassembly-friendly structure and an open-source mindset. This allows hobbyists and developers to rapidly prototype through 3D printing or redesign it to meet personalized needs.
The gripper features a swappable claw system, making it easy to exchange claws of different shapes for alternative use cases. All parts are fully 3D-printable at home with minimal support required. The wiki below provides a step-by-step guide for assembly.
Dimensions/Operating Range
The dimensions and operating range are shown below in millimeters, with variable height depending on the claws used.
Drive Mechanisms
This gripper features a classical Dual Crank & Slider mechanism, translating rotational to axial motion.
- Crank & Slider Showcase:
- Motion Simulation Showcase
BOM
🔩 Fasteners
| Name | Quantity |
|---|---|
| Phillips Pan Head Screw PM3×8 | 8 |
| Hex Socket Cap Screw M3×20 | 4 |
| Hex Socket Cap Screw M3×25 | 6 |
| Hex Socket Cap Screw M3×50 | 8 |
| Hex Socket Cap Screw M3×16 | 12 |
| 304 Nylon Locking Hex Self-Locking Nut M3 (Thickness-3.9mm × Width-5.5mm) | 18 |
| Spring Washer – M3 | 4 |
| Flat Washer – M3×7mm (OD) × 0.5mm (Thickness) | 8 |
⚙️ Bearing
| Name | Quantity |
|---|---|
| F3-8M Miniature Thrust Bearing (ID-3mm × OD-8mm × Thickness-3.5mm) | 4 |
🛠️ Linear Motion
| Name | Quantity |
|---|---|
| Stainless Steel Linear Rail MGN9, 200 mm | 1 |
| Linear Rail Carriage MGN9C (Standard) | 2 |
🔌 Actuator
| Name | Quantity |
|---|---|
| DM4310-2EC Motor | 1 |
🧩 Custom Printables
| Name | Quantity |
|---|---|
| 3D Printed Parts | 1 set |
Assembly Guide
3D-Printing Guide
-
If you have dedicated support material or PETG+PLA in your AMS and want the best surface finish on supported faces, please refer to This Wiki.
Note: your print job may take longer. -
If you only have one filament to print, make sure you print with the correct orientations and decide whether you need the following steps (Turn On ADVANCED in Bambu Studio).
warningDo not change the Top Z distance if you are using PETG or ABS. Keep them as default. Only change this if you use PLA.
- Step 1: Print layout with minimal supports required
- Step 2: Scarf Settings provide a better surface finish as marked in Green Rectangles.
- Step 3: My Print Settings: 0.2mm layer height, 25% infill density, Style – 3D Honeycomb.
Step By Step Assembly Walkthrough
- Step 1: Fix the Claw Holders to the MGN9C sliders with eight M3×8 mushroom-headed screws
- Step 2: Stack the bearings, rotors, and linkages ("hamburger" style)
- Step 3: Place eight M7 washers above and below the slots
- Step 4: Place four nuts above and below the washers
- Step 5: Screw four pairs of M3×20 screws and spring washers to the nuts (use pliers if necessary)
- Step 6: Place the Base and Actuator in position; the patterns on the rotor plate and actuator should align
- Step 7: Screw six M3×16 screws to secure the rotor plate to the actuator
- Step 8: Push the claw base to the maximum range for the next steps
- Step 9: Attach the cam holder to the bottom
- Step 10: Fix the cam holder with four pairs of M3×25 screws and nuts
- Step 11: Fix the base with six M3×16 screws (Pull out the rail for this stage and slide it back in afterwards)
- Step 12: Use two pairs of M3×50 screws and nuts to lock the rail on the base
- Step 13: Slide the rail presser in and secure with two pairs of M3×25 screws and nuts
- Step 14: Place the claws on the claw holders, and secure them with six pairs of M3×50 screws and nuts
Demos and CAD Files
- Follow the Damiao Actuators Wiki to get everything set up if you haven't done so.
- Follow the Torque Controller Demo (many thanks to tianrking) to get the gripper moving with a cool GUI.
- The CAD resources: editable STEP files and STLs are available here.