FFF 3D-Print Mega Sumo Robot

This is a mega sumo robot that can be made with an FFF 3D printer and some hand tools.

See here for the Robot Sumo Tournament.

Conventional mega-sumo robots require machine tools to process metal and CFRP, and this has been a major obstacle to making mega-sumo robots. So I designed a machine tool-free mega-sumo robot that you can build in your own living room. I hope that this initiative will increase the number of participants in Mega Sumo Robot tournaments.

I also hope that you will design and share your own 3D-Print Mega Sumo Robot.

CAUTION: This robot uses powerful magnets, high-powered motors, sharp knives, and lithium-ion batteries. These are very dangerous if handled incorrectly, so please do not build this robot if you do not have the expertise to handle them.

Only a brief explanation follows. Please refer to the 3D data for the basic assembly method.

3D printer

• Print range of 200 x 200 x 200 (mm) or more.
• The printer must be able to print ABS filament.

Hand tools

• Drill Bit 3.0mm
• Drill Bit 3.2mm
• Drill Bit 4.0mm
• Drill Bit 5.0mm
• Drill Bit 5.1mm
• Drill Bit 6.0mm
• Hand Drill
• Screwdriver Phillips No0
• Screwdriver Phillips No1
• Screwdriver Hex 1.5mm
• Screwdriver Hex 2.5mm
• Diamond Precision File
• Precision File
• Precision Side Cutter
• Snap-off Utility Knife
• Hot Melt Glue Gun
• Sand Paper
• Soldering Iron
• Machine Vise
• Scissors
• Metal Cutting Shears
• Putty Knife
• Cut-resistant gloves

Purchased parts

• 3D Printer Filament ABS
• 3D Printer Filament Nylon
• Glue
• Double-sided Tape
• Brake Parts Cleaner
• PERMATEX Screw Lock Red
• Soldering Wire
• Parts described in BOM

Create STL data from 3D data [FFF 3D-Print Mega Sumo Robot Ver1.0 v2.f3d].

Print the parts.

Please refer to the figure for the molding direction of the 3D print parts.

The gear uses Nylon filament. Others use ABS filament. See BOM for details.

Be careful not to warp the 3D printed parts.

Make sure the 3D printed parts are sized according to the data. Adjust the 3D printer if the size of the data and the output part are different.

• 3D printer
• 3D Printer Filament ABS
• 3D Printer Filament Nylon
• Putty Knife
• Precision Side Cutter
• Drill Bit 3.0mm
• Drill Bit 3.2mm
• Drill Bit 4.0mm
• Drill Bit 5.0mm
• Drill Bit 5.1mm
• Drill Bit 6.0mm
• Hand Drill
• Precision File

Cut off the protrusion of the Blade base.

Then smooth the surface with a file.

• Precision File
• Precision Side Cutter
• Blade base (1)

Sanding the magnet and blade base pocket.

Apply glue to both the blade base and the magnet. and glue it.

The magnetic pole pattern is either all N or all S.

• Glue
• Sand Paper
• Magnet D15t2 (8)
• Blade base (1)

Sanding the magnet and frame pocket.

Apply glue to both the frame and the magnet. and glue it.

The magnetic pole pattern alternates between N and S.

• Glue
• Sand Paper
• Outer frame R (1)
• Outer frame L (1)
• Inner frame R (1)
• Inner frame L (1)
• Magnet D20t5 (14)

Sanding the magnet and frame pocket.

Apply glue to both the frame and the magnet. and glue it.

Arrange the magnetic pole pattern so that the Top cover and the Stopper attract each other.

Once the magnet is fixed, fix the top cover and stopper with the shaft.

• Glue
• Sand Paper
• Top cover (1)
• Stopper (1)
• Magnet D8t3 (2)
• Stainless steel (303) precision shaft φ3L45 (1)

After installing the nut, fix it with hot bond.

Once the glue has hardened, cut off any excess glue.

• Hot Melt Glue Gun
• Snap-off Utility Knife
• Cut-resistant gloves
• Blade base (1)
• No5 blade (1)
• M2.6 Nut 3 types (5)
• Screw_M2.6 Plate No. 0 Type 3 L5 (5)

After installing the nut, fix it with hot bond.

Once the glue has hardened, cut off any excess glue.

Attach the motor holder to the inner frame.

• Hot Melt Glue Gun
• Screwdriver Phillips No0
• Screwdriver Hex 2.5mm
• Snap-off Utility Knife
• Cut-resistant gloves
• Outer frame R (1)
• Outer frame L (1)
• Inner frame R (1)
• Inner frame L (1)
• Center frame (1)
• M2.6 Nut 3 types (8)
• Screw_M2.6 Plate No. 0 Type 3 L10 (8)
• Motor holder (2)
• M3 nut Type 3 (6)
• Hex socket head bolt M3x30 (6)

Cut the Shim plate with Metal Cutting Shears.

File the cut surface.

Place the Shim plate in the machine vise. Then bend the plate slightly.

Apply double-sided tape to the Shim plate. Then stick it on the blade base.

• Snap-off Utility Knife
• Cut-resistant gloves
• Machine Vise
• Double-sided Tape
• Metal Cutting Shears
• Shim plate hardened steel t0.3W100L200 (1)
• Blade base (1)

Cut the rubber pipe.

Clean the inside of the cut rubber pipe with brake cleaner.

Assemble the cut rubber pipe and wheel.

Glue the wheel and rubber pipe.

• Snap-off Utility Knife
• Cut-resistant gloves
• Brake Parts Cleaner
• Glue
• Wheel (2)
• Natural Rubber (NR) Pipe Hardness 60 [Set of 2] (1)

Fit the small gear into the hole of the large gear.

If your gear is wobbly, resize your 3D print.

• Gear ASSY_A _small gear (2)
• PS1-40J18 Spur gear (2)

Install bearings on gears and wheels.

• Wheel (2)
• Bearing D13d6t5 (4)
• Gear ASSY_A (2)
• Bearing D10d6t3 (4)
• Gear assembly_B (2)
• Bearing D10d5t4 (4)
• Gear m1Z16t12d8 (2)
• Bearing D8d4t3 (4)
• Spacer_3D printing_D7.8d5.8t4 (2)

Clean motor shaft and gear holes.

Apply Screw Lock to the motor shaft. and attach the gear. At this time, be careful not to let the Screw Lock get into the motor bearings.

At this time, secure a gap between the gear and the motor case. If there is no clearance, the gear will not rotate properly.

Stand the motor and wait for the gear to be fixed.

Install the set screw in the screw hole of the motor.

• PERMATEX Screw Lock Red
• Screwdriver Hex 1.5mm
• MAXON DCX35L (2)
• Gear m1Z14t12d6 (2)
• M3L5 Stainless Hex Socket Set Screw/Flat Point Nissan Screw (12)

Soldering the harness to the motor.

• Soldering Iron
• Soldering Wire
• Precision Side Cutter
• MAXON DCX35L (2)
• Silicone cord 16AWG (1)
• XT30 connector female (2)

Insert the set screw into the Center frame.

Insert bolts and nuts.

Center the shaft in the Center frame. Then fix it with a screw.

• Screwdriver Hex 1.5mm
• Center frame (1)
• Linear shaft φ6L200 (1)
• Linear shaft φ5L200 (5)
• Linear shaft φ4L40 (1)
• Stainless steel (303) precision shaft φ3L145 (1)
• M3L5 Stainless Hex Socket Set Screw/Flat Point Nissan Screw (5)
• M2 nuts Type 3 (1)
• Hex socket head bolt M2x10 (1)

Sharpen and round the edge of the blade with a file.

• Diamond Precision File
• No5 blade (used, rounded edge) (2)

Assemble the Motor driver assembly according to the diagram and circuit diagram.

Write the program in the attached file [RC_Read3.ino] to the Arduino micro.

Be sure to test run the Motor driver assembly before incorporating it into the robot.

• Soldering Iron
• Soldering Wire
• Precision File
• Machine Vise
• Screwdriver Phillips No1
• Precision Side Cutter
• Substrate base (1)
• Board cover (1)
• Double-sided through-hole universal board 4*6 (1)
• Photocoupler TLP785 (GB rank) (4)
• Pololu High-Power Motor Driver 36v20 CS (4)
• NPN digital transistor DTC114EL (2)
• Capacitor 63V100uF (5)
• 9V, 600mA Step-Down Voltage Regulator D36V6F9 (1)
• Arduino Micro (1)
• Screw_Iron + pan B tight 2x6 (4)
• Screw_Iron + pan B tight 2x10 (8)
• XH connector post with base 5P (2)
• XH connector housing 5P (2)
• Contacts for XH connectors (14)
• Contact N for XH connector (14)
• XH connector post with base 4P (2)
• XH connector housing 4P (2)
• wire cord for XH connector (1)
• 3-pin connector for radio control signals (2)
• 3 wire cord for radio control signals (2)
• Radio control receiver (1)
• Anderson Connector 1327Red (1)
• Anderson Connector 1327Black (1)
• Anderson Connector Contact 15Amp (2)
• XT30 connector male (2)
• Breaker fuse 40A (1)
• Silicone cord 14AWG (1)
• Silicone cord 16AWG (1)
• Copper wire #16*1m (1)

Attach the connector to the battery as shown.

CAUTION: Never short circuit the battery. A fire will occur.

• LiPo 1300mAh 3S (2)
• LiPo 1300mAh 2S (2)
• Anderson Connector Contact 15Amp (4)
• Anderson Connector Contacts 30Amp (2)
• Anderson Connector 1327Black (2)
• Anderson Connector 1327Red (4)

Assemble the robot by referring to the video.

• Screwdriver Phillips No0
• Screwdriver Hex 1.5mm
• Screwdriver Hex 2.5mm