Propeller blades can have an important impact on the power of a drone, which in turn affects the flight of the drone. But with a wide variety of propellers on the market today and different functions, how should a drone choose a propeller to improve flight efficiency? This issue of MAD COMPONENTS will introduce you to the knowledge of propellers.

What is a propeller

Propeller is an important part of UAV power system hair, when it is installed to the UAV, the lift generated by rapid rotation will take the UAV into the air. Propeller is one of the power system of UAV, the material is usually wood, plastic, carbon fiber, etc., according to the parameters of the aircraft requirements to choose.

Propeller specification type

Propeller specifications, generally indicated by 4 digits, the first two digits indicate the diameter and the last two indicate the pitch.

Take 1060 pulp as an example, 10 means the diameter of the propeller is 10 inches, 60 means the angle of the pulp. (Pitch, 6.0 inches, which is 152.4mm).

The relationship between the number of paddles and efficiency

The fewer the paddles, the higher the efficiency. If a quadrotor and a six-rotor UAV with similar wheelbase, battery specifications and the same takeoff weight are compared, the flight time of the quadrotor is greater than that of the six-rotor.

What does the propeller do

For planters, the downward pressure wind field generated by the propeller is an effective aid to crop spraying.

The downward pressure wind from the propeller makes the leaves shake, which can spray the drug mist to the front and back of each leaf. The atomization rate of pesticides is improved, while the penetration rate of the mist stream is enhanced, reducing drug loss and increasing the utilization rate of pesticides by at least 30%. Therefore, the effect of pesticide spraying by drones is significantly higher than that of manual spraying.

How to adapt the propeller

The choice of propeller is related to the motor KV value.

Generally the motor with larger KV value chooses high speed propeller (small size propeller), while the motor with smaller KV value chooses low speed propeller (large size). And the same motor, different KV value, with different propellers, relatively speaking, the propeller with too small, can not play the maximum thrust; propeller with too large, the motor will overheat, will make the motor demagnetization, resulting in a permanent decline in motor performance, that is, a small horse-drawn car or big horse-drawn car problem. When the motor specifications are the same, the smaller the KV value, the larger the motor pitch and the lower the speed, so choose a large pitch and large size propeller; the larger the KV value, the smaller the motor pitch, but the high speed, so choose a small pitch and small size propeller. Motor specifications are different, when the KV value is the same, the larger the motor diameter and height, representing the larger the motor power, you need to choose a large pitch and large size propeller to improve efficiency.

For example.

(1) two same 10kg 4-axis UAV, the same 8120 motor model, one is 100kv value, one is 140kv value. There are 3090 paddles and 2911 paddles, so 100kv is suitable for 3090 paddles and 140kv is suitable for 2911 paddles.

(2) two 10kg 4-axis UAV, one for the 7020 motor model, one for the 8120 motor model, the motor value is 140kv. 2488 paddles and 2911 paddles, the 7020 motor is adapted to 2488 paddles, 8120 motor is adapted to 2911 paddles. (The above motor and paddle models are for case illustration only, the actual model to the manufacturer's production shall prevail, the principle is the same)

How to maintain the propeller

1. Check the appearance of the propeller blade for bends, breaks, cracks, etc. Please discard the propeller with this problem.

2、Check whether there are pesticide residues and stains under the propeller of plant protection machine. Pesticide residue will destroy the aerodynamic shape of the propeller, reduce the flight efficiency, and eventually increase the cost of plant protection operations.