You must be wondering what equipment is responsible for ensuring that the aerial photography capabilities of your quadcopter function well. The motor is responsible for the aerial movements of the quadcopter that let you capture cinema grade aerial videos.
This article is geared towards providing you information about the fundamentals of multirotor motors so that you are able to purchase the best one for your quadcopter. There is a wide variety of motor designs available on the market and you should buy the one which suits your budget as well as meets all your requirements.
Things to consider when choosing drone motors
Weight of your drone
The first and foremost thing that you should take into account while purchasing a motor for your quadcopter is the overall weight of the drone. You can figure out the overall weight of your drone by calculating the weight of individual components. But you should ensure that all the components such as payload if a camera along with a gimbal are connected, battery unit, motors, wires, Power Distribution Board, flight controller and chassis of the contraption. If you are familiar with the size and weight of the propellers, it will help you out in determining the overall thrust of the motors that will be needed to ensure that the drone is lifted properly during flights. This will in turn impact the speed of the drone in the air and the weight will assist you in the flight time adjustments.
Thrust to weight ratio
The rule of thumb for selection of the right motor is that it should enable the drone to hover midair with half throttle. This implies that the chosen motor should generate about 50% more thrust in contrast to the multirotor. This is a mandatory parameter since it means that the motor should produce additional thrust to keep the drone secure during windy weather or while performing aerial acrobatics.
The formula used for the determination of motor efficiency is “thrust/power used in W”. So, the overall unit for the quantity becomes g/W. A higher value means that motor is more efficient and will ensure that the drone undergoes longer flights. According to experts, a motor with an efficiency rating around 7 is what you should be looking to get. There is a likelihood that a motor could be efficient with its lower throttle range. In such a case, they will lose efficiency with increasing current range at higher limits. When a motor with lower efficiency is connected to a drone unit, then a lot of compensation has to be made in terms of flight timing and energy. This also tends to drain the battery voltage at a higher rate. So, it is imperative that you take into account the thrust to current ration of the motor when purchasing a drone motor.
The torque range assists in defining the capacity of a motor to shift between RPM values. This variation is responsible for determining the sensitivity of a drone midair. A drone with a higher value of torque means that the drone’s response will be the least desired as the RPM will go through faster changes. It will also lead to a lesser propeller wash. A drone with a higher torque value does imply that the drone is able to run bulkier propellers but will also tend to draw more current. If you attempt to run a heavier propeller on a low torque motor, the required value of RPM will not be attained or the motor will not be able to produce sufficient torque for rotation. Ultimately, lower thrust will be produced and hence lesser current will be sucked from the system. Having said that, there is a drawback of connecting high torque motors: more vibrations are produced and they cannot be damped easily. High torque motors are able to produce quicker response rates so users can shift between disparate RPM variations with ease. It may also magnify error and produce vibrations even at the yaw axis.
Motor pole count is another important aspect that should be taken into consideration while purchasing a motor for your quadcopter. There are two options available with regard to this aspect: firstly, quadcopter motors with higher value of pole count. These motors generate greater torque but simultaneously draw more voltage for their functioning. Keep in mind that such motors will produce lower RPM. Experts are of the view that larger blades should be chosen for such motors.
The second kind of motors tend to have a lower value of pole count but they generate higher RPM. Such motors are used along with smaller blades and perform with smaller lift from the ground. If you want to avoid using an additional gear box, then you should use a motor with a higher pole count.
Types of motors
Brushed DC Motors
Such motors boast a rotating armature that functions similar to an electromagnet with two poles. A rotary switch is attached that tends to reverse the direction of the current for every half cycle so that poles can be pushed or pulled against permanent magnets connected outside motor. These motors are typically used as a source of power for drones and provide a run time of up to 1000 hours. Pilots have to spend money on the continuous maintenance for carbon brushes in order to ensure appropriate proper energy consumption and functioning.
Brushless DC Motors
Brushless DC motors do not come with brushes since they are equipped with a permanent magnet that is switched with electronic polarity variations. The motion is controlled with the help of an electronic controller and speed feedback mechanism. These motors are used for drones that require higher speed of rotation to manage flights and generally offer a run time of more than 1000 hours. These motors are highly efficient and conserve energy efficiently.
What’s the verdict?
If you require motors to work for a smaller duration of time, then brushed DC motors are the way to go since they will generate enough output while ensuring cost effectiveness. But in case you are going to need motors to function continuously or when your quadcopter requires a higher power rating, then brushless motors are the preferred choice in order to get higher flight durations.
Coolplay syma x5c-1 x5c x5 motors
- Designed with brass metal gear that promises to offer efficient performance with reliability
- Their wire color codes are similar as the original models so the replacement process is easier and affordable
- Overall performance is as high as default motors
- These motors are supported by all Syma X designs
- Satisfactory customer service
- Reliable and stable design
- Frustrating sounds are produced
Hobbymate quadcopter kit motor
- An ideal choice for FPV QAV quadcopters having a size range of 250, 210, 180 and smaller drones
- Remarkable air suction system
- Integrated with U clip to prevent loosening of bearings
- Highly accurate CNC machine
- Top quality design
- Fast cooling system
- Longer battery lifespan with higher efficiency
- Light in weight
- Offers longer flight duration
- Lesser vibrations with low CG design
Parrot AR Drone 2.0 motor
- The motor boasts an optimum power of 15 watts and has the ability of completing about 28000 rotations per minute midair
- Range of these motors beings at 10,350 RPM till 41,400 RPM
- The speed of the motor is controlled with the help of a 8 bit low power type microcontroller along with a 10 bit ADC
- Can be easily installed
- Consumes lesser power and produces higher efficiency
- Safe with long and short screw connections
- Offers high performance
- Slightly expensive
Hobbypower A2212 brushless motor
- Brushless motor that ensures service with KV value of 1000
- 30A advanced speed controller unit
- Optimum speed of 2100000 RPM with 2 poles type BLM and approximately 70,000 RPM with 6 pole type
- Price range is low
- Stays cool even during harsh flying conditions
- Augments more power to the RC drone
- Motor tends to get heated up quickly
- Generates lots of oscillations during motor acceleration
Emax Mt2213 brushless motor
- Remarkable multirotor motor design
- Top quality response performance
- Multirotor options for octo, hexo, quad and tri
- Optimum thrust goes up to 860G
- Easy to configure
- Formidable design
- Balanced and smooth motors
- Optimum weight is 55 grams