Despite the amount of work still necessary to create the kinds of robots seen in movies, humanoid robotics has significantly advanced over the centuries and in recent decades. Thanks to their smaller size, ability to run off batteries, and the efficiencies they offer, custom BLDC motors have contributed to the cutting-edge industry. The more life-like a humanoid robotic application is, the more sophisticated engineering is required of brushless DC motor manufacturers.
BLDC Motor Overview
A BLDC, or brushless DC, motor uses a stator with windings connected to control electronics, as well as a rotor with permanent magnets. It does not use brushes or a mechanical commutator. To function, the stators magnetic fields rotate around the rotor. The stator then leads the rotor magnet, switching as the rotor and stator align. The alternating current changes the polarity, creating a push-pull-like effect. The design results in no sparks, which is ideal for robotics applications.
Benefits of BLDC motors in robotics applications include:
- No need to worry about a brush’s life
- No brush residue
- Ease of maintenance
- Low electrical noise
- Faster maximum speed
- Cleaner operation
- Improved efficiency
- Better reliability
- The ability to fit into compact spaces
- The ability to run off batteries
- Extended lifespan
Controlling a BLDC motor necessitates a means to detect the magnetic poles, or the rotor’s angular position, needed to create the feedback signals required to control the semiconductor switching devices. A commonly used position sensor is a Hall Effect sensor. Optical sensors are another option. BLDC motor manufacturers can design “outrunner” motors to have an internal electromagnet stator and an external permanent magnet rotor for greater torque at lower speeds. This may eliminate the need for a gearbox.
The Use of Brushless DC Motors in Humanoid Robots
Instead of large motors, humanoid robotic applications use microdrives that brushless DC motor manufacturers design to give robots human traits and avoid making them excessively heavy. BLDC motor microdrives in a robot’s neck and waist, for example, allow it to be expressive. Actuators allow the torso and head to move independently and display different postures.
Microdrives aren’t just replicas of larger brushless DC motors. They provide high short-term overload capabilities without affecting lifespan, which is ideal for allowing a humanoid to exhibit certain gestures. The use of stepper motors allows for accurate positioning without the need for additional encoders. Furthermore, the motors run efficiently even with minimal supply voltages, making them a good choice for systems with battery backups that won’t fail in the event the voltage drops. Brushless DC motor manufacturers can set up microdrives to have custom, application-specific speeds, output torque and other specific variables with different gear motor combinations.
One of the greatest advantages of microdrives is the flexibility they offer. The BLDC motors are more dynamic, efficient and have a higher output despite their small size. As a result, frequent heavy loads are possible without affecting service life. This is beneficial for momentary actions that aren’t frequent. The overall advantages seen in robotic medical aids that use microdrives over the last few decades, such as motor-powered hand and leg prosthetics, demonstrates that custom BLDC motors can meet strict medical requirements.
Putting the muscle in humanoid robot manufacturing, BLDC motors offer the best options in regard to dynamics and service life. The range of applications and designs for brushless motors is wide. With a BLDC motor catalog filled with components to build and control microdrives, Sinotech positions you to be at the forefront of humanoid robotics technologies. Our manufacturers are prepared to build custom BLDC motors to your exact specifications. If your robotics ideas are still a work in progress, Sinotech’s engineers will help you develop your designs and pair you with trusted manufacturing facilities. Learn more by contacting Sinotech today.