40kg.cm Metal Serial Bus Servo, High Precision And Large Torque, With Programmable 360 Degrees Magnetic Encoder and Brushless Motor

SKU: 24702
Part Number: ST3025 Servo
Brand: Waveshare


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40kg.cm Metal Serial Bus Servo, Wide Range Voltage, High Precision And Large Torque, With Programmable 360 Degrees Magnetic Encoder and Brushless Motor, Two-Way Feedback, Servo/Motor Mode Switchable
40kg.cm metal serial bus servo

Metal case, with Brushless Motor and 360° Programmable Magnetic Encoder

Product type ST3025 serial bus servo
Torque 40kg.cm@12V
Rotation angle 360° (0~4095)
Position sensor resolution 0.088° (360°/4096)
Mechanism limit angle No Limit
Working voltage 6 ~ 12.6 V (typ. 12V)
Gear high precision steel gear
No-load speed 0.117sec/60° (85RPM)
Encoder type 12Bits magnetic encoder
ID range 1 ~ 253
Baudrate 38400bps ~ 1Mbps (1Mbps by default)
No-load current 380mA
Locked-rotor current 4.4A
Kt 9kg.cm/A
Feedback Position, Load, Speed, Input Voltage, Current, Temperature

Application Examples
  • Servos will provide various feedback like load, position, speed, input voltage, working current, working mode (servo mode, servo motor mode, etc.) for advanced projects requiring closed-loop automatic control.
  • Ideal choice for building quadruped robots, hexapod walkers, robotic arms and other robotic projects requiring multiple servos. (This product provides the open source models as shown in the picture below)

Download models:

Download models:

Download models:

Download models:

* images here are for reference ONLY

UART Serial Bus Control

Allows controlling up to 253 serial bus servos at the same time

Note: though one channel UART can control up to 253 serial bus servos, due to the high power of the servos, it is necessary to consider whether the power supply solution is enough when using too many servos. For reference only, the servo driver board is NOT included

Easy to use, Large Torque

Supports 6.0~12.6V Wide range Voltage Input, And Can Be Directly Powered By 3S lithium batteries. Up To 40kg.Cm Torque On 12V Voltage, Suitable For Building Quadruped Robots, Hexapod Walkers, Robotic Arms And Other Robotic Projects Requiring Multiple Servos

All-aluminum alloy case + brushless motor + steel gear box

Adopts high-reliability Design, suitable for industrial equipments, robotics, and other application scenarios that require angle or speed closed-loop control

360° Magnetic Encoder
High Precision, Longer Lifetime

Adopts 12-bit high-precision magnetic encoding angle sensor. Compared with the carbon film potentiometer, the angle of the magnetic encoder is enlarged to 360°, and the resolution is increased by 4 times. Since there is a gap and no friction between the magnetic encoder and the radial magnet, the lifetime of the servo is effectively extended.

Acceleration Start-stop Function

The speed and acceleration values are settable to make the motion effect softer

One Button to Calibrate the Middle Position

360° installation at any position, one button to set the current position as middle position. Easy to install and debug

1. In the default program, a hotspot will be created automatically after the servo driver board is turned on. Use your mobile phone to connect to this hotspot, open the browser, and enter the IP address to enter the control interface.

2. Click Release to unlock, then turn the servo to the middle position where you need to set

3. Click Set Middle Position then confirm.

4. Turn the servo to any angle, then click Middle, and the servo will automatically return to the middle position initially set.

Two-Way Feedback

The Servo Will Provide Various Feedback Like Position, Load, Speed,
Input Voltage, Current and Temperature In Real Time

* images here are for reference ONLY

Multiple operation modes
suitable for more application scenarios

Angle servo mode
Default mode, the angle position is controllable at 0~360° degrees

Speed closed-loop motor mode
Motor mode, intelligently control and maintain speed when the load changes

Step mode
Can perform step motion relative to the current position

Multi-Loop angle Position control

Supports angle position control in both positive and negative directions up to 7 loops under the default precision setting, but the number of loops will not be saved in case of power loss. Lowering the angle resolution can double the number of control loops

Supports installing flat-shaft flange

With the flat-shaft flange designed for this serial bus servo, the output shaft of the servo can be installed on more devices, making full use of various working modes and excellent low-speed performance. It can be used to install various transmission parts such as 6mm shaft couplings, wheels, timing pulleys, and gears.

* images here are for reference ONLY

All-metal servo bracket

More Convenient to Develop the Structural Components, Combination Use More Flexible

Details Introduction

Aluminium Alloy Case
Improved heat tolerance, size stability, rigidity, and mechanical performance

High strength aluminum servo wheels
Using T6061 aluminum alloy, good anti-corrosion performance

High precision steel gears
Lower working noise, better stability and mechanical performance

All-metal bracket
More convenient to combine it with other devices

Open Source Control Program

We provide the open-source web control demo of the servo driver board and a secondary development tutorial, which can be directly used for remote setting and remote control of the servo. At the same time, we also provide a 3D model for you to build your project quickly.

product show

Outline dimensions
Resources & Services

* Resources for different product may vary, please check the wiki page to confirm the actually provided resources.

Product Selection
Product Voltage Control Method Precision NO-LOAD SPEED Continuous Rotation LOCKED-ROTOR TORQUE * LOCKED-ROTOR CURRENT Range Feedback
WP90 4.8 ~ 7.4 PWM ≤2° 0.1sec/60° - 2.3kg.cm 1.0A 180° -
SC09 4.8 ~ 8.4 TTL 300°/1024 0.1sec/60° 2.3kg.cm 1.0A 300°
SC15 4.8 ~ 8.4 TTL 180° / 1024 0.16 sec / 60° 15kg.cm 1.5A 180°
ST3020 6 ~ 14.0 TTL 360° / 4096 0.167sec / 60° 25kg.cm 2.7A 360°
ST3215 6 ~ 12.6 TTL 360° / 4096 0.222 sec / 60° 30kg.cm 2.7A 360°
ST3025 6 ~ 12.6 TTL 360° / 4096 0.117sec / 60° 40kg.cm 4.4A 360°
ST3235 6 ~ 12.6 TTL 360° / 4096 0.222sec/60° 30kg.cm 2.7A 360°
RSBL45-24 9.0 ~ 24.0 RS485 360° / 4096 0.142sec/60° 45kg.cm 2.3A 360°
RSBL85-12 9.0 ~ 12.0 RS485 360° / 4096 0.167sec/60° 85kg.cm 7.9A 360°
RSBL85-24 9.0 ~ 24.0 RS485 360° / 4096 0.154sec/60° 85kg.cm 5.6A 360°
RSBL120-24 9.0 ~ 24.0 RS485 360° / 4096 0.2sec/60° 120kg.cm 4A 360°

* the Locked-rotor torque is measured at the typical voltage of each servo, please refer to the documentation in the wiki for more details

Weight: 0.124 kg

Quick Overview

ST3025 Servo x1