How to choose between harmonic reducer, planetary reducer, and RV reducer?

Harmonic reducer, planetary reducer, and RV reducer have significant differences in their applicable scenarios. The core selection logic is as follows:

① Harmonic reducer: small in size, light in weight, high in transmission accuracy, and large in transmission ratio, suitable for scenarios with limited space and high precision requirements, such as industrial robot joints, precision instruments, and humanoid robots. However, its load-bearing capacity is relatively weak, and the flexible wheels are prone to fatigue;

② Planetary reducer: high rigidity, long service life, cheap price, better load-bearing capacity than harmonic reducer, suitable for scenarios with low precision requirements and high loads, such as ordinary automated production lines and conveying equipment;
③ RV reducer: Strong load-bearing capacity, high rigidity, long service life, precision close to harmonic reducer, suitable for heavy-duty and high-precision scenarios, such as large industrial robots and heavy-duty robotic arms, but with large volume and weight, the price is relatively high.

In the application of lightweight humanoid robots, harmonic reducers are usually the main type, supplemented by planetary reducers.