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Bill of Materials

AlohaMini follows the same architecture and terminology as LeKiwi, consisting of a Client side and a Host side.

  • The Client handles computation and control.
  • The Host executes commands and returns observations.

This is also commonly referred to as PC side vs. Remote side, and both naming conventions are equivalent.

AlohaMini’s Client hardware includes the mobile base and two follower arms. The arms directly reuse the SO-ARM100 design. Therefore, if you already have two SO-ARM100 arms, you only need to assemble the mobile base. Communication between the mobile base, arms, and Raspberry Pi 5 uses the same bus-servo communication system, and the build guide will explain the wiring in detail.

On AlohaMini, the Host side consists of a PC workstation and leader arms. VR controllers or other devices can also replace the leader arms, and we will release compatible controller kits soon. For beginners, we recommend starting with leader-arm teleoperation.

Note: Table clamp, screwdriver set, soldering iron, and other common tools can be sourced as needed and are not listed in the tables below.

Mobile base

Item Model / Notes Qty Unit Cost (US) Buy (US) Unit Cost (CN) Buy (CN)
Servo motor Feetech / 12V 1/345 Gear(STS3215-C018) 4 $13.89 Alibaba ¥110 taobao
Omni wheel 4″ (≈100 mm) 3 $47 Amazon ¥135 pinduoduo
USB camera 720p focal length 2.4 mm, 36×36 mm form factor 3 Amazon ¥125 taobao
(optional) Bearing 12×18×4 mm (ID × OD × W) — wheel axle bearing 3 Amazon ¥6 tmall
Bearing 4×13×5 mm (ID × OD × W) — lift axis bearing 8 Amazon ¥3 taobao
M2×12 Phillips screw For camera mounts (OB_T_Camera_Mount.stl, OB_Top_Camera_Mount) 12
M3×12 hex socket screw Total 36 pcs (Servo Mount×24 ,Side Panel×12 ) 36
M3×18 hex socket screw For OB_Chassis_Wheel_Axle_Connector.stl 12
M3×30 hex socket screw For OB_T_Connector_Right/Left.stl 8
M3 hex nut For OB_T_Connector_Right/Left.stl 8
M3x5x4 heat-set insert Total 36 pcs (Servo Mount×24, Side Panel×12) 36 Amazon ¥5 taobao
M4×12 hex socket screw Total 20 pcs (Bearing Cover×12, Z-axis Servo Mount×8) 20 Amazon
M4x6x5 heat-set insert For OB_Chassis_Bearing_Cover.stl 12 Amazon ¥4 taobao
Adhesive Double-sided tape / epoxy — cable retention & structural bonding 1 Amazon ¥12 jd
Servo extension cable SCS 3-pin, 90 cm 2 Alibaba ¥3 taobao
Battery 12 V Li-ion pack with 5521 barrel jack (male & female); one pack for the Raspberry Pi 5, the other for the mobile base and follower arms. 2 $43 Amazon ¥130 taobao
USB Type-C cable Only for testing the mobile base 1 $10 Amazon ¥20 tmall
Waveshare Bus Servo Controller Only for testing the mobile base 1 $13 Amazon ¥27 tmall
3D-printed parts PLA/PETG/ABS (files in /hardware/mobile_base/stl) ~4 kg filament

3D Printing Parts List:

  • OB_Chassis_Bearing_Cover x3
  • OB_Chassis_Servo_Mount x3
  • OB_Chassis_Side_Panel x3
  • OB_Chassis_Wheel_Axle_Connector x3
  • OB_Chassis_Wheel_Guard x3
  • OB_Top_Camera_Back_Cover x2
  • O_Chassis_Dowel_Pin_12_24 x3
  • O_Chassis_Dowel_Pin_12_37 x3
  • All other files x1

What the Base Can Do

With only the components above, you can assemble the mobile base and control:

  • movement
  • vertical lift

Use the following commands to control the base:

python examples/debug/wheels.py \
   --port /dev/ttyACM0

python examples/debug/axis.py \
   --port /dev/ttyACM0

Use W/S/A/D to drive the base, and U/J to raise or lower the lift — all directly from your PC, without installing any single-board computer on the robot.

More details will be provided in the software setup section.

Effect after assembly:

Assembled AlohaMini mobile base

Standalone Mode (Optional)

If you prefer the base to operate as an independent host system (Wi‑Fi, untethered), add:

Item Model / Notes Qty Unit Cost (US) Buy (US) Unit Cost (CN) Buy (CN)
Compute board Raspberry Pi 5 (4GB/8GB) 1 Adafruit ¥600 taobao
DC converter 12V → 5V / 5A buck converter 1 $13 Amazon ¥75 taobao
Monitor 7-inch HD IPS HDMI interface + touch + Type C power supply 1 Amazon ¥291 taobao

Follower Arms

Item Model / Notes Qty Unit Cost (US) Buy (US) Unit Cost (CN) Buy (CN)
Servo motor Feetech / 12V 1/345 Gear(STS3215-C018) 12 $13.89 Alibaba ¥110 taobao
Waveshare Bus Servo Controller For connecting to the Raspberry Pi 5 2 $13 Amazon ¥27 tmall
USB camera 720p focal length 3.8 mm, 36×36 mm form factor 2 Amazon ¥103 taobao
1-to-2 DC splitter cable 30 cm, 5521 connector — for powering the arms 1 Amazon ¥5 taobao
DC extension cable 1.5 m, 5521 connector — for powering the arms 2 Amazon ¥2.50 taobao
USB Type-C cable For connecting to the Raspberry Pi 5 2 $10 Amazon ¥20 tmall
3D-printed parts PLA/PETG/ABS (files in /hardware/arms/stl) 1 set

3D Printing Parts List:

  • All "D_*.stl" files: x2
  • All "F_*.stl" files: x2

For detailed printing instructions, refer to the SO-ARM100 project README

Leader Arms

Note: The official SO-ARM100 design uses three different gear ratios (1/147, 1/191, 1/345) for optimal performance. However, our testing shows that using a single gear ratio (1/147) provides excellent user experience and significantly simplifies assembly. The BOM below reflects this simplified configuration.

Item Model / Notes Qty Unit Cost (US) Buy (US) Unit Cost (CN) Buy (CN)
Servo motor Feetech / 7.4V 1/147 Gear(STS3215-C046) 12 $13.89 Alibaba ¥99 taobao
Waveshare Bus Servo Controller For connecting to the PC 2 $13 Amazon ¥27 tmall
Battery 5V Li-ion pack (5600mAh) 1 Amazon ¥30 taobao
1-to-2 DC splitter cable 70 cm — for powering the arms 1 Amazon ¥5 taobao
USB Type-C cable For connecting to the PC 2 $10 Amazon ¥20 tmall
3D-printed parts PLA/PETG/ABS (files in /hardware/arms/stl) 1 set

3D Printing Parts List:

  • All "D_*.stl" files: x2
  • All "L_*.stl" files: x2

For detailed printing instructions, refer to the SO-ARM100 project README