The common hub motor is DC brushless motor, and the control method is similar to that of the servo motor. But the structure of the hub motor and the servo motor is not exactly the same, which makes the ordinary method for selecting the servo motor not fully applicable to the hub motor. Now, let's take a look at how to choose the right hub motor.
The hub motor is named according to its structure, and is often called an external rotor DC brushless motor. The difference from the servo motor is that the relative position of the rotor and the stator is different. As the name implies, the rotor of the hub motor is located on the periphery of the stator. So compared with the servo motor, the hub motor can generate more torque, which determines that the application scene of the hub motor should be low-speed and high-torque machines, such as the hot robotics industry.
When designing the servo system, after selecting the type of the servo system, it is necessary to select the actuator. For the electric servo system, it is necessary to determine the model of the servo motor according to the load of the servo system. This is the matching problem between the servo motor and the mechanical load, that is, the power method design of the servo system. The matching of servo motor and mechanical load mainly refers to the matching of inertia, capacity and speed. However, in the selection of servo hubs, the meaning of power is weakened. The most important indicators are the torque and speed，different loads and different application of the servo hub motor. How to select torque and speed?
1.The weight of the hub motor
Generally, service robots will be selected by weight. The weight here refers to the total weight of the service robot (robot self-weight + load weight). Generally, we need to make sure the total weight before making a selection. The weight of the motor is determined, basically conventional parameters such as torque are determined. Because the weight limits the weight of the internal magnetic components, which affects the torque of the motor.
2.Overload capability
The climbing angle and the ability to climb over hurdles are also an important indicator for the selection of service robots. When climbing, there will be a gravitational component (Gcosθ) that makes the service robot need to overcome the work, and it needs to output a larger torque; in the same way, a tilt angle will also be formed when climbing a ridge. It also needs to overcome the gravity to do work, so the overload capability (that is, maximum torque) will greatly affect the ability to climb the ridge.
3.Rated speed
The significance of emphasizing the parameter of rated speed here is that it is different from the usage scenarios of conventional motors. For example, the servo system often uses motor + reducer to obtain greater torque. However, the torque of the hub motor itself is large, so using the corresponding torque when exceeds its rated speed will cause greater loss, resulting in overheating or even damage to the motor, so it is necessary to pay attention to its rated speed. Usually controlled within 1.5 times to its capacity to obtain the best results.
Since its establishment, Shenzhen Zhongling Technology Co., Ltd. has been focusing on the R&D, production and performance optimization of hub motors, providing customers with first-class products and solutions with the values of focus, innovation, morality and pragmatism.
Post time: Nov-02-2022