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Electric Unicycle Product

Overview

An electric unicycle (EUC) is a self-balancing personal vehicle built around a single in-wheel motor. The rider stands on two folding pedals straddling the wheel and steers by leaning. There are no handlebars and no throttle: speed and direction come entirely from body weight shifts, which the machine reads and answers by driving the wheel. The whole drivetrain, battery, and electronics pack into a Shell & Housing no wider than the tire, so the vehicle is compact enough to carry into a building once the Telescoping Handle is extended and the unit is wheeled like luggage.

This configuration runs an 84 V pack and a direct-drive hub motor, giving a 50 km/h top speed and 60–75 km of range. The pedals fold flush against the shell for transport, and TPU bumpers protect the body from tip-overs.

How it works

Balance is the core trick. A 6-axis IMU Module measures the wheel's pitch angle and rotation rate hundreds of times a second. The Control Board runs a closed-loop controller: when the rider leans forward, the frame pitches, the IMU reports the tilt, and the controller commands motor torque to drive the wheel under the rider's center of mass. The faster the lean, the harder it drives. Leaning back reverses the torque and brakes. Because the loop only ever tries to keep the wheel beneath the rider, accelerating, cruising, and stopping are all the same control action expressed at different lean angles.

Torque reaches the road through the Hub Motor, an outer-rotor BLDC whose magnets ring the inside of the wheel rim. Hall sensors track rotor position so the inverter can commute the three phases, switching the high pack current through an IGBT stage with a MOSFET gate path. Energy comes from the Battery Pack, a 20S3P lithium pack whose BMS balances cells and clamps charge and discharge limits; at speed the same path runs in reverse, feeding regenerative braking energy back into the cells.

Two safety interlocks gate the drive. Each Foldable Pedal carries a presence sensor, so the motor refuses to spin unless a rider is standing on the pedals. As the unit approaches its speed ceiling it performs a tilt-back, pitching the pedals up to physically push the rider to ease off, and sounds a warning through the kit speaker. Configuration, speed limits, and firmware updates are handled wirelessly through the onboard Bluetooth module and the rider's phone app.

Build & assembly graph

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Bill of materials

10 top-level lines · 61 rows shown · 176 parts total · indented to 3 levels
# Item / sub-assembly Part no. Qty/assy Ext. qty Parts Type
1 Shell & Housing 3 parts electric-unicycle-shell-assembly 1 7 assembly
1.1 Shell Half electric-unicycle-shell-half 2 part
1.2 Corner Bumper electric-unicycle-bumper 4 part
1.3 Fastener Set fastener-set 1 part
2 Hub Motor 8 parts electric-unicycle-hub-motor 1 62 assembly
2.1 Stator Assembly 3 parts stator-assembly 1 3 assembly
2.1.1 Stator Core (laminations) stator-core 1 part
2.1.2 Copper Winding copper-winding 1 part
2.1.3 Slot Insulation stator-insulation 1 part
2.2 Rotor Assembly 4 parts rotor-assembly 1 19 assembly
2.2.1 Rotor Shaft rotor-shaft 1 part
2.2.2 Rotor Core rotor-core 1 part
2.2.3 Neodymium Magnet neodymium-magnet 16× 16 part
2.2.4 Ball Bearing ball-bearing 1 part
2.3 Copper Winding copper-winding 1 part
2.4 Neodymium Magnet neodymium-magnet 32× 32 part
2.5 Ball Bearing ball-bearing 2 part
2.6 Hall Sensor hall-sensor 3 part
2.7 Motor Axle electric-unicycle-motor-axle 1 part
2.8 Pneumatic Tire electric-unicycle-tire 1 part
3 Control Board 9 parts electric-unicycle-control-board 1 19 assembly
3.1 Bare PCB pcb-bare 1 part
3.2 Microcontroller mcu 1 part
3.3 IMU Module 3 parts electric-unicycle-imu-module 1 3 assembly
3.3.1 IMU (6-axis) imu 1 part
3.3.2 Bare PCB pcb-bare 1 part
3.3.3 SMD Passive (R/C/L) smd-passives 1 part
3.4 Power MOSFET mosfet 6 part
3.5 IGBT Power Module igbt-module 1 part
3.6 Hall Sensor hall-sensor 1 part
3.7 SMD Passive (R/C/L) smd-passives 1 part
3.8 Heatsink electric-unicycle-heatsink 1 part
3.9 Connector connector 4 part
4 Battery Pack 4 parts electric-unicycle-battery-pack 1 63 assembly
4.1 Li-ion Cell, 18650 li-cell-18650 60× 60 part
4.2 BMS Board bms-board 1 part
4.3 Pack Frame electric-unicycle-pack-frame 1 part
4.4 Wire Bundle wire-bundle 1 part
5 Foldable Pedal 4 parts electric-unicycle-pedal-assembly 2 4 assembly
5.1 Pedal Plate electric-unicycle-pedal-plate 2 part
5.2 Pedal Hinge electric-unicycle-pedal-hinge 2 part
5.3 Pedal Sensor electric-unicycle-pedal-sensor 2 part
5.4 Fastener Set fastener-set 2 part
6 Telescoping Handle 4 parts electric-unicycle-handle-assembly 1 5 assembly
6.1 Handle Grip electric-unicycle-handle-grip 1 part
6.2 Telescope Tube electric-unicycle-telescope-tube 2 part
6.3 Handle Latch electric-unicycle-handle-latch 1 part
6.4 Fastener Set fastener-set 1 part
7 LED Light Kit 4 parts electric-unicycle-light-kit 1 6 assembly
7.1 LED Strip electric-unicycle-led-strip 2 part
7.2 Speaker speaker 1 part
7.3 Connector connector 2 part
7.4 Wire Bundle wire-bundle 1 part
8 Charging Port 2 parts electric-unicycle-charge-port 1 2 assembly
8.1 DC Charge Jack electric-unicycle-dc-jack 1 part
8.2 Connector connector 1 part
9 Bluetooth Module 3 parts electric-unicycle-bt-module 1 3 assembly
9.1 Bare PCB pcb-bare 1 part
9.2 BLE SoC electric-unicycle-bt-soc 1 part
9.3 SMD Passive (R/C/L) smd-passives 1 part
10 Wire Bundle wire-bundle 1 part

Sourcing — likely vendors

Companies that make this · indicative price $300–$15k · MOQ & lead are typical
VendorHQSpecialtyMOQLead time
🇨🇳InMotion
inmotionworld.com ↗
Shenzhen, CN electric unicycles made to order 10–16 wks
🇨🇳King Song
kingsong.com ↗
Shenzhen, CN electric unicycles made to order 10–16 wks
🇨🇳Begode
begode.com ↗
Beijing, CN electric unicycles made to order 10–16 wks
🇨🇳Veteran
veteran-sheng.com ↗
Shenzhen, CN electric unicycles made to order 10–16 wks

427-word article