Sizing a motor for the Servo Arduino application needs you to consider some factors. You need to check the torque and profile requirements to know the mechanical needs of your system. You need to know things such as peak torque and RMS values, most acceleration and velocity, and the likes. Once you have selected the motor, the next thing is to opt for the drive.

Choosing servo drives may appear to be about matching current output and drive voltage to the need of the motor. There are diverse factors you need to consider for the drive to work. Some applications would need you to have more specialized functions from the drive, here are some factors that influence the choice of Servo Arduino drive for the majority of applications.

1. Motor types usually paired using servo drives

Servo drives can get used along with any type of motor which functions within a closed-loop system such as induction, stepper, and asynchronous. There are two popular motor types out there that get paired with servo drives and they are synchronous AC motor and brushless DC motors. The synchronous AC motors are the most common with motion control applications.

2. Commutation triggered by a servo drive

The communication type which the drive requires hinges upon the motor type that gets driven and the sensitivity of the application to torque ripple. Brushless DC motors are often able to function using sinusoidal or trapezoidal motion, AC motors can function using sinusoidal. Six step commutation is the easiest method as it uses three hall sensors to know the commutation sequence.

What sinusoidal commutation does is to remove the torque ripple and give it more accurate control by changing the supplied current. There is a need for a high-resolution feedback mechanism to track the position of the rotor.

3. Feedback

Note that Servo systems need feedback to give closed-loop operation and correct possible errors in the position, velocity, and torque of the motor. The feedback may get provided using resolver, sensors, and encoders. Irrespective of the feedback system, the drive has to be compatible with the signal for it to process it and relay information to and fro the controller.

4. Current and voltage

Another application of the Servo Arduino is in the current and voltage. The current and voltage have to be enough to produce the much needed mechanical output by the motor. Because the operation of the drive and motor are closely linked, manufacturers will make available torque speed curves that show the performance of certain motor-drive combos.

5. Operating mode

The Servo loops in the drive help to regulate velocity, torque, and position. Even though all Servo drives make use of a torque control loop and velocity control loop, it is only digital drives that can give position regulation.

One unique thing about Servo drives is that they come with multi-loop builds along with the current loop within the velocity loop which is within the position loop. Analog drives can give velocity and current control. However, only digital drives will give position loops.

6. Digital or analog

Servo drives were analog and got used to convert voltage signals from the controller into current to regulate the velocity and torque. For one to be able to regulate an analog drive, certain parameters have to be set using potentiometers. Using newer digital drives, the command can get executed using analog or digital commands, and tuning gets done using the software.

Added to velocity, torque, and position loop, digital drives may get used to coordinate advanced functions like path generation. Also, digital drives may get used to tracking certain internal functions of the drive besides giving a comprehensive fault diagnosis.

7. Communication

For the Servo Arduino drive and controller to communicate, there must be a common language in play. For this to get done, the Servo drives get presented using different conversational systems. Some of these protocols are basic while others are more advanced. Your choice of protocol hinges on the speed of communication you desire.

Final thoughts


Understanding how Servo works will help you maximize its potentials as it has to do with daily life applications. Knowing how to choose the right driver will save you a lot of time, energy, and resources in the long run.