In the research, development, and quality testing of electric motors—particularly servo motors, BLDC motors, and electric vehicle (EV) motors—measuring cogging torque is a critical evaluation process. 

Cogging torque is generated by the interaction between the rotor's permanent magnet field and the stator slots when the motor rotates without load. Although the magnitude of this torque is typically very small, it has a direct impact on motor smoothness, vibration levels, and precision control performance. 

However, cogging torque measurement is also one of the most challenging tests to perform. Many conventional torque measurement systems lack the sensitivity required to accurately detect extremely small torque fluctuations, leading to errors in motor evaluation and design optimization. 

Ultra-Low Torque Measurement with UTMIII

As the exclusive distributor of Unipulse force and torque measurement solutions in Vietnam, Temas introduces the UTMIII, a high-precision torque sensor specifically engineered to meet the most demanding measurement requirements. 

With a minimum measurement range starting at just 0.05 Nm, the UTMIII can accurately capture extremely small torque values that are difficult—or even impossible—to measure using conventional equipment. This enables engineers to effectively evaluate cogging torque as well as other critical motor performance characteristics. 

In addition to its exceptional sensitivity, the UTMIII features a highly rigid sensor shaft that ensures stable measurements even when motors are operating at high rotational speeds. As a result, it is particularly well suited for motor performance testing in the EV industry and other advanced motion-control applications. 

Key Advantages of the UTMIII

The UTMIII was developed to deliver an optimal combination of accuracy, durability, and reliable operation in real-world testing environments: 

• Compact and lightweight design for easy integration into test systems. 
• Non-linearity of only 0.03%, ensuring highly accurate measurements. 
• Maximum rotational speed of up to 40,000 rpm. 
• Safe overload capacity of up to 500%. 
• A mechanical design that minimizes the influence of radial and axial loads on the sensor, helping maintain measurement stability and accuracy. 

More Than Just Cogging Torque Measurement

Thanks to its high-resolution torque measurement capability and high-speed operating performance, the UTMIII is not limited to cogging torque analysis. It is also widely used for: 

• Electric motor performance evaluation. 
• Mechanical wear analysis of drive systems. 
• Starting torque measurement. 
• Servo motor and stepper motor testing. 
• Electric vehicle (EV) motor research and development. 
• Gearbox and precision transmission system testing. 

With its exceptional accuracy and ability to measure ultra-low torque values, the UTMIII has become an ideal solution for R&D laboratories, testing centers, and motor manufacturers that demand the highest measurement standards. 

The video below demonstrates how cogging torque measurement can be performed using the UTMIII in a real-world testing environment:

With extensive experience implementing measurement solutions across industries such as electronics, semiconductors, precision engineering, and industrial automation, Temas does more than simply supply equipment. We work closely with customers to select and optimize the most suitable force and torque measurement solution for each specific application.  

Temas is an authorized distributor of Unipulse force sensors and force indicators in Vietnam. If you are looking for a force or torque measurement solution for vacuum environments, extreme temperatures, or high-precision applications, contact Temas for expert consultation and assistance in selecting the configuration that best fits your system requirements.