Comparatif des servomoteurs Dynamixel

How to choose the right Dynamixel servomotor?

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The Dynamixel range is a sound choice for use in robotics. These servo motors are developed by the Korean company Robotis, and rank among the most powerful and efficient on the market.
Dynamixel servos are used in many research laboratories and universities the world over. They were developed especially for designing robots.

Why Dynamixel servo motors are so special

The Dynamixel servos by Robotis are built around a very high quality Maxon electric motor (XH, MX and Pro series), coupled with an ARM microcontroller.

They are ultra-precise and offer a wide range of features, which we have detailed for you below.

A very diverse range

There are many different types of Dynamixel servo motors, ranging from a small servo for use by a robotics club to a powerful industrial quality servo.

A wide variety of uses

Servos can serve many different purposes, for example in industry, aerospace, defence, medical equipment, education, to build robotic arms or mobile platforms, service robots, etc.

A simple, all-in-one system

How does a Dynamixel servomotor work?

Dynamixel servomotor = DC motor + controller + driver + sensor + reduction gear + network

These are all-in-one servos, so no additional elements are required to use them except for a power supply and communication interface.

Modular

These servos are modular, thanks in particular to the many structural components available.

Daisy-chain communication (cleaner assemblies)

There is a single BUS for controlling all your servo motors (daisy-chained), with RS-485 or TTL type communication. This greatly reduces the number of necessary cables, which is a definite advantage for embedded projects (some Georgia Tech robotics engineers have successfully chained over 250 servos).

Data feedback

Data feedback and control: position, speed, temperature, torque, etc.

Low energy consumption

These servos operate on a high voltage and low power consumption, meaning greater battery stability.

Compatible with many programming languages

Dynamixel is compatible with various programming environments, including:

  • Roboplus, the visual software by Robotis dedicated to programming Dynamixel servo motors
  • The SDK (access to source codes and libraries for Windows, Linux and smartphones)
  • C/C++, JAVA, MATLAB, LABVIEW, ROS

PID control and corrections

Some series offer PID control and corrections – simply specify the values (P, I, D), and the motor will use the PID independently (MX, Pro and PRO PLUS series)

Servo status LEDs

Dynamixel servos include LEDs that indicate the status of the servo (overheating, servo motor ready, etc.).

Which Dynamixel servo for which project?

The Dynamixel range is divided into series, each with its own specific features.

We have detailed them below:

AX series

The AX series is a group of entry-level Dynamixel servos. They use the TTL protocol. They are a good choice for non-essential mechanical robot functions.
Uses: learning robotics, light prototypes, wheel motorisation. They are used in Trossen robotic arms.

AX-12A : one of the most popular in the entire Dynamixel range on account of its price. It is a little more powerful than the AX-12W, but much slower.

AX-12W : similar to the AX-12A but with a much higher rotational speed, designed to power the wheels of mobile robots.

AX-18A : an AX-12A with more torque, making it a more powerful and durable servo motor. It is the fastest and most powerful in the AX range (but also more expensive).

 Servomotor  Input Voltage [V]  Stall Torque [N·m]  Stall Current [A]  No Load Speed [rpm]  Link (Physical)  Dimensions (lxHxP) [mm]  Weight [g]
 AX-12A  9-12  1.50  1.5  59  TTL  32 X 50 X 40  54.60
 AX-12W  9-12  0.21  1.4  470  TTL  32 X 50 X 40  52.90
 AX-18A  9-12  1.80  2.2  97  TTL  32 X 50 X 40  55.90

MX series

A step up from the AX series, the MX series offers advanced features such as more precise position control, PID correction (less backlash), 360° position control and fast communication. They are more powerful and robust and offer better control of high speed and precision movements.
Uses: research robots, humanoid robots, more advanced prototypes. They are used in the Poppy (Humanoid and Torso versions) and ROBOTIS-OP humanoid robots.

 Servomotor  Input Voltage [V]  Stall Torque [N·m]  Stall Current [A]  No Load Speed [rpm]  Link (Physical)  Dimensions (lxHxP) [mm]  Weight [g]
 MX-12W  10-14.8  –  –  470  TTL  32 X 50 X 40  54.60
 MX-28T  10-14.8  2.50  1.4  55  TTL  35.6 X 50.6 X 35.5  72
 MX-28R  10-14.8  2.5  1.4  55  RS485  35.6 X 50.6 X 35.5  72
 MX-28AT  10-14.8  2.50  1.4  55  TTL  32 X 50 X 40  77
 MX-28AR  10-14.8  2.50  1.4  55  RS485  32 X 50 X 40  77
 MX-64T  10-14.8  6  4.1  63  TTL  40.2 X 61.1 X 41  126
 MX-64R  10-14.8  6  4.1  63  RS485  40.2 X 61.1 X 41  126
 MX-64AT  10-14.8  6  4.1  63  TTL  40.2 X 61.1 X 41  135
 MX-64AR  10-14.8  6  4.1  63  RS485  40.2 X 61.1 X 41  135
 MX-106T  10-14.8  8.4  5.2  45  TTL  40.2 X 65.1 X 46.0  153
 MX-106R  10-14.8  8.4  5.2  45  RS485  40.2 X 65.1 X 46.0  153

XL series

The XL series is a group of small servo motors designed for rapid prototyping (including combined with 3D printing), small robots and for use in education.
The XL430-W250-T has the same mechanical structure as and is compatible with the XM430 and XH430. Dynamixel XL-320 servos are used in the Robotis Mini humanoid robot, in the Poppy Ergo Jr and in the Metabot.

 Servomotor  Input Voltage [V]  Stall Torque [N·m]  Stall Current [A]  No Load Speed [rpm]  Link (Physical)  Dimensions (lxHxP) [mm]  Weight [g]
 XL-320  6-8.4  0.39  1.1  114  TTL  24 X 36 X 27  16.70
 XL430-W250-T  6.5-12  1.50  1.4  61  TTL  28.5 X 46.5 X 34  57.20

XM and XH series

The XM and XH series offer significant advantages with torque, speed, position and even PWM control!
The XH series is of a slightly higher quality (Maxon motor). Although they have a lower maximum speed and torque than those in the XM series, the servos in the XH series are more durable and more energy efficient.
For more information on this series, we suggest that you read our Dynamixel XM-430 servo test.

 Servomotor  Input Voltage [V]  Stall Torque [N·m]  Stall Current [A]  No Load Speed [rpm]  Link (Physical)  Dimensions (lxHxP) [mm]  Weight [g]
 XH430-V210-R  24  2.60  0.7  52  RS485  28.5 X 46.5 X 34  82
 XH430-V350-R  24  3.30  0.7  31  RS485  28.5 X 46.5 X 34  82
 XH430-W210-R  10-14.8  2.50  1.3  50  RS485  28.5 X 46.5 X 34  82
 XH430-W210-T  10-14.8  2.50  1.3  50  TTL  28.5 X 46.5 X 34  82
 XH430-W350-R  10-14.8  3.40  1.3  30  RS485  28.5 X 46.5 X 34  82
 XH430-W350-T  10-14.8  3.40  1.3  30  TTL  28.5 X 46.5 X 34  82
 XH540-V150-R  24  6.40  2.4  60  RS485  33.5 X 58.5 X 44  165
 XH540-V270-R  24  9.20  2.4  34  RS485  33.5 X 58.5 X 44  165
 XH540-W150-R  10-14.8  7.10  4.9  70  RS485  33.5 X 58.5 X 44  165
 XH540-W270-R  10-14.8  9.90  4.9  39  RS485  33.5 X 58.5 X 44  165
 XH540-W270-T  10-14.8  9.90  4.9  39  TTL  33.5 X 58.5 X 44  165

 Servomotor  Input Voltage [V]  Stall Torque [N·m]  Stall Current [A]  No Load Speed [rpm]  Link (Physical)  Dimensions (lxHxP) [mm]  Weight [g]
 XM430-W210-R  10-14.8  3  2.3  77  RS485  28.5 X 46.5 X 34  82
 XM430-W210-T  10-14.8  3  2.3  77  TTL  28.5 X 46.5 X 34  82
 XM430-W350-R  10-14.8  4.10  2.3  46  RS485  28.5 X 46.5 X 34  82
 XM430-W350-T  10-14.8  4.10  2.3  46  TTL  28.5 X 46.5 X 34  82
 XM540-W150-R  10-14.8  7.30  4.4  53  RS485  33.5 X 58.5 X 44  165
 XM540-W150-T  10-14.8  7.30  4.4  53  TTL  33.5 X 58.5 X 44  165
 XM540-W270-R  10-14.8  10.60  4.4  30  RS485  33.5 X 58.5 X 44  165
 XM540-W270-T  10-14.8  10.60  4.4  30  TTL  33.5 X 58.5 X 44  165

Dynamixel Pro

The Dynamixel Pro series combines unparalleled quality and exceptional power and precision. Dynamixel Pro servos offer position, speed and torque control. They can be programmed in many languages, including C#, Java, Python, LabVIEW, MATLAB, etc.
They are ideal for advanced robotics and industrial applications and are used in a large majority of the robots created by laboratories the world over. They are a good choice for human-scale humanoid robots (e.g. THOR-OP), advanced mobile platforms and grippers.
They use the RS-485 protocol and benefit from PID correction. They are

Dynamixel PRO PLUS

Released in 2019, the servo motors in the Dynamixel PRO PLUS series are more reliable and robust than those in the Pro series for a similar cost. This series has replaced the Dynamixel Pro series.

 Servomotor  Input Voltage [V]  No Load Speed [RPM @ V]  Courant à vide [A @ V]  Continuous Speed [RPM @ V]  Continuous Torque [N.m @ V]  Continuous Current [A @ V]  Backlash [Arcmin]  Resolution [steps/turn]  Dimensions (lxHxP) [mm]  Weight [g]
 Pro H42-20-S300-R  24  32.7 @ 24  0.57 @ 24  29.2 @ 24  5.1 @ 24  1.5 @ 24  3.8  303.750  42 x 42 x 84  340
 PRO PLUS H42P-20-S300-R  24  32.7 @ 24  0.57 @ 24  29.2 @ 24  5.1 @ 24  1.5 @ 24  3.8  607.500  42 x 42 x 84  340
 Pro H54-100-S500-R  24  33.3 @ 24  1.13 @ 24  29.2 @ 24  25.3 @ 24  5.5 @ 24  3.5  501.923  54 x 54 x 108  732
 PRO PLUS H54P-100-S500-R  24  33.3 @ 24  1.13 @ 24  29.2 @ 24  25.3 @ 24  5.5 @ 24  3.5  1003.846  54 x 54 x 108  740
 Pro H54-200-S500-R  24  33.1 @ 24  1.65 @ 24  29 @ 24  44.7 @ 24  9.3 @ 24  3.5  501.923  54 x 54 x 126  855
 PRO PLUS H54P-200-S500-R  24  33.1 @ 24  1.65 @ 24  29 @ 24  44.7 @ 24  9.3 @ 24  3.5  1003.846  54 x 54 x 126  855