Home Engineering Small Unmanned Fixed-Wing Aircraft Design. A Practical Approach
Rare-earth Brushless Electric Motors
While we most often use IC engines for our UAVs, small, powerful brushless electric motors based on rare-earth magnets are now available in a wide range of sizes so there is a much greater choice of units than for IC engines. Obviously, such motors must be supported by
Table 5.2 Typical IC engine BMEP values taken from various sources.
Note that BMEP values are typically 10-15% higher at the maximum torque speed as compared to maximum power speed and also that by assuming a BMEP of 1.0 MPa, it is possible to estimate the likely achievable peak power of a four-stroke UAV engine at a range of engine speeds.
Figure 5.10 Hacker brushless electric motor.
battery packs, fuel cells, or on-board generators (hybrid systems). In the world of multi-rotor UAVs, they are extremely widely used, and many commercial camera-carrying systems adopt these technologies. They are smooth, powerful, and highly reliable devices since they involve so few moving parts. Their Achilles heel remains the short endurances that are possible with conventional LiPo battery packs, though these continue to improve. We tend to use the motors made by Hacker along with their Master Spin controllers. Brushless motors readily provide powers from a few tens of watts up to 15 kW, see Figure 5.10.
|< Prev||CONTENTS||Next >|