In modern robotics design, the choice of motor directly affects a robot’s performance, stability, and cost. Among the commonly used DC motor types, sensored motors and sensorless motors are two widely adopted solutions. So, which type is more suitable for robotic applications? This article will analyze their working principles, performance characteristics, and practical use cases.
Basic Differences Between Sensored and Sensorless Motors
The key feature of a sensored motor is its built-in position sensor, usually a Hall sensor or optical encoder, which provides real-time feedback on the rotor’s position. The controller uses this feedback to precisely adjust the motor’s energizing sequence, ensuring smooth startup and stable operation.
In contrast, sensorless motors lack internal sensors and rely on estimating rotor position through back electromotive force (EMF) calculations. This design reduces mechanical components and sensor costs, but may experience delayed response and jitter at low speeds or under high-precision demands.
Performance Comparison
For low-speed startup and high-precision control, sensored motors have clear advantages. By detecting rotor position in real time, they achieve virtually jitter-free startup and precise speed and position control. This makes them ideal for collaborative robots, robotic arms, or precision handling robots.
Sensorless motors, on the other hand, are more suitable for high-speed continuous operation. Without sensors, they have a simpler structure, lower cost, and easier maintenance, making them well-suited for mobile robots or drive-wheel systems where precise control is less critical.
Application Scenarios
For industrial robots and service robotic arms, sensored motors are often the preferred choice. Their precise control ensures stable operation during tasks such as picking, assembly, or dispensing. Especially in low-speed operations or frequent startups, sensored motors maintain smooth motion and reduce vibrations or impact forces.
For transport robots, AGVs, or low-cost inspection robots, sensorless motors offer advantages. They perform efficiently at high speeds, have a simplified structure that reduces system costs, and minimize maintenance risks associated with sensor failure.
Selection Recommendations
When selecting a motor, it is essential to define the robot’s operational requirements. If tasks demand high-precision positioning, smooth control, and reliable low-speed startup, sensored motors should be prioritized. If tasks prioritize high-speed operation, cost-efficiency, and a simple structure, sensorless motors are more suitable. Modern control technology has improved low-speed performance for some sensorless motors, but sensored motors still dominate precision applications.
Conclusion
In summary, choosing between a sensored or sensorless motor for robots depends on application needs and performance priorities. Sensored motors offer precise control and smooth startup, making them ideal for high-precision tasks. Sensorless motors provide a simple, cost-effective solution with excellent high-speed performance, making them suitable for mobile and transport robots. Proper motor selection not only enhances overall robot performance but also optimizes system cost and reliability, making it a crucial consideration in robotics design.