SACA Mechatronics 2

Question 1

Which type of motor is most commonly used in precision positioning applications within mechatronic systems due to its ability to move in discrete steps?

Accepted Answer

Stepper motor

Answer

Stepper motors divide a full rotation into equal discrete steps, enabling precise open-loop position control without encoders — ideal for applications like 3D printers, CNC routers, and pick-and-place machines.

Question 2

In mechatronics, what is the purpose of a planetary gearbox attached to a servo motor?

Accepted Answer

To increase torque and reduce speed while maintaining compact dimensions

Answer

A planetary gearbox multiplies torque by the gear ratio while proportionally reducing speed, in a compact coaxial arrangement — matching high-speed, low-torque motor output to low-speed, high-torque application requirements.

Question 3

What does a Hall-effect sensor measure in a brushless DC motor controller?

Accepted Answer

Rotor magnetic pole position for commutation timing

Answer

Hall-effect sensors detect the rotor's magnetic field orientation, providing the controller with rotor position information needed to correctly time the switching of stator phase currents (electronic commutation).

Question 4

In a mechatronic system, what is the role of a digital-to-analog converter (DAC)?

Accepted Answer

To convert digital control commands from a microcontroller into analog voltage or current signals

Answer

A DAC converts the digital output of a microcontroller or DSP (a numeric value) into a proportional analog voltage or current signal, which is used to drive analog-input actuators such as proportional valves or servo amplifiers.

Question 5

What is 'backlash' in a mechanical transmission system and why is it problematic in precision mechatronics?

Accepted Answer

The dead zone between gear teeth where no motion is transmitted, causing positioning error

Answer

Backlash is the clearance (play) between mating gear teeth or lead screw/nut threads. When direction reverses, the motor moves through the backlash gap without moving the load, creating positioning errors and reduced control loop stability.

SACA - Smart Automation Certification Alliance Practice Test

SACA - Smart Automation Certification Alliance Practice Test

SACA Mechatronics 2