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20kg.cm Bus Servo Motor, 106PRM High Speed, Large Torque, With 360 Degrees High Precision Magnetic Encoder
A high-performance 20kg·cm bus servo motor (model ST3215-HS) with 360-degree high-precision magnetic encoder and UART serial bus control. It supports both se...
A high-performance 20kg·cm bus servo motor (model ST3215-HS) with 360-degree high-precision magnetic encoder and UART serial bus control. It supports both servo mode (precise angle control) and motor mode (continuous rotation), making it versatile for robotics applications from robotic arms to wheeled platforms.
The UART bus interface allows daisy-chaining up to 253 servo motors on a single channel, with real-time two-way feedback for position, load, speed, and input voltage. The 12-bit magnetic encoder provides 4× the resolution of traditional potentiometer-based servos with no mechanical wear.
Key Features
- 20kg·cm Torque at 12V – High torque for demanding robotics applications
- 106 RPM High Speed – Fast response for dynamic movements
- 360° Magnetic Encoder – 12-bit precision with no contact wear
- UART Serial Bus Control – Daisy-chain up to 253 servos
- Dual Mode – Servo mode (angle control) and motor mode (continuous rotation)
- Two-Way Feedback – Real-time position, load, speed, and voltage data
- Acceleration Control – Settable speed and acceleration for smooth motion
- One-Button Middle Position Calibration – Set any position as centre point
Specifications
- Model: ST3215-HS
- Torque: 20kg·cm (at 12V)
- Speed: 106 RPM
- Encoder: 12-bit magnetic, 360°
- Control Interface: UART serial bus
- Modes: Servo (angle) / Motor (continuous)
- Gears: High-precision copper and steel
- Case: Nylon and fibreglass composite
- Servo Wheels: T6061 aluminium alloy
- Design: Dual-shaft, low-profile, compact
Ideal For
- Quadruped robots and hexapod walkers
- Robotic arms and multi-joint assemblies
- Wheeled robots requiring closed-loop speed control
- 3D printers and CNC projects
Package Contents
- 1× ST3215-HS Bus Servo Motor
Resources
Jargon buster
Plain-language definitions for the technical terms used above.
- encoder
- A device attached to a motor or shaft that reports movement, such as rotation steps or position. In a pump system, an encoder can help measure or control how much the motor has turned, which affects how repeatable the watering amount can be.
- potentiometer
- A variable resistor usually turned with a knob or shaft to create an adjustable electrical signal. It is often used for inputs such as volume, brightness or position, so it helps beginners learn how a microcontroller reads changing values.
- servo
- A servo is a motor with built-in position control, usually told to move to a specific angle by a control signal. It matters when you need repeatable movement, such as steering, arms, flaps, or linkages, rather than continuous spinning.
- servo motor
- A motor module that moves to a commanded angle rather than simply spinning freely. It matters for robotics and mechanisms because it is useful for steering, arms, gates and other parts that need controlled position.
- Torque
- A twisting force that causes something to rotate, usually measured in newton-metres or kilogram-centimetres. It matters when choosing motors, servos, gears, and tools because higher torque is needed to lift heavier loads, turn larger wheels, or move mechanisms without stalling.
- UART
- UART is a simple serial connection that sends data over separate transmit and receive wires, often labelled TX and RX. It matters because this module is designed to replace a wired UART cable with a wireless link while keeping the same serial data format.
Find this product in
Robotics & Motion
