### Category: Propellers

QuadCopter DC Motor(BLDC) + Propeller Dynamics

## QuadCopter DC Motor(BLDC) + Propeller Dynamics

Ultimately we’ll buy Electronic Speed Controllers (ESCs) for our Quad motors. They take PWM in and produce drive voltages for brushless DC motors. Let’s jump in to understand the motor-propeller subsystem on a quadrotor. DC Motor Modelling You’ll find basic DC motor equations in any undergraduate dynamics textbook. I add the Bouabdallah model for the …

In  the last quadcopter post we clarified the load torque of the propeller applied through the gearbox to the motor shaft. We won’t even have a gearbox but the terms in the equation needed clarification. We haven’t yet covered the main point of the propeller: LIFT! A propeller blade is just a spinning wing at each …

Quadrotor Dynamic Model: Propeller Gyroscopic Effect.

## Quadrotor Dynamic Model: Propeller Gyroscopic Effect.

The equations below are from the last post, where we see we matched our Bouabdallah paper‘s equations for rotational motion. We know some propeller input is going to be a part of the applied torque. There is going to be a set of equations for linear motion too, but let’s clarify what is going on …

Finalizing Equations Of Motion: Thrust Inputs from Propellers

## Finalizing Equations Of Motion: Thrust Inputs from Propellers

This post explains how we determine propeller thrust and drag factors for our quadcopter project. The last couple posts have been working-out the sum-of-torques on our quad-copter. We covered gyroscopic effect of the total air-frame in the, “equations of motion” post a few weeks ago. Next we looked at the torque induced by the gyroscopic …

Maximum Thrust vs. Battery Voltage

## Maximum Thrust vs. Battery Voltage

In a previous post we got the Ardupilot simulator stable running the linear-quadratic attitude controller, but we had a hack in-place for normalizing our body torque commands from Newton-meters to -1 to +1 for input to the Ardupilot motor sub-system. Purpose This post uses a test stand to measure maximum available thrust over a range …