Servo Motor Question & Answers July 27, 2023 By Wat Electrical This article lists 100 Servo Motor MCQs for engineering students. All the Servo Motor Questions & Answers given below include a hint and a link wherever possible to the relevant topic. This is helpful for users who are preparing for their exams, interviews, or professionals who would like to brush up on the fundamentals of Servo Motor. A servo motor is a type of rotary actuator that allows for precise control of angular position. It is widely used in various applications that require precise motion control, such as robotics, industrial automation, aerospace, and model-making. Servo motors have a closed-loop control system, which means they constantly receive feedback about their current position and adjust their rotation accordingly to reach the desired position accurately. Most servo motors consist of a DC motor combined with a set of gears to reduce the motor's high-speed, low-torque output to a lower-speed, higher-torque output. This gearing mechanism enhances the motor's ability to maintain a steady position. Servo motors are often controlled using PWM signals. The control signal is sent as pulses with varying widths, and the motor interprets the pulse width to determine the desired position. It's essential to choose the right servo motor for a specific application based on factors such as torque requirements, speed, physical size, and communication protocol compatibility. 1). What is a servo motor? A motor used in heavy machinery A motor used in robotics and automation A motor used in household appliances A motor used in vehicles Hint 2). Which of the following is NOT a type of servo motor? AC servo motor DC servo motor Stepper servo motor Linear servo motor Hint 3). What principle allows a servo motor to achieve precise control? Induction Inertia Feedback Resistance Hint 4). Which component of a servo motor is responsible for providing feedback? Encoder Transistor Capacitor Diode Hint 5). Which type of servo motor is more suitable for high-speed applications? AC servo motor DC servo motor Both a and b None of the above Hint 6). What is the unit of measurement for servo motor speed? Volts Watts Hertz RPM Hint 7). Which motor characteristic defines the amount of load a servo motor can handle? Power rating Torque rating Voltage rating Efficiency Hint 8). Which of the following is a disadvantage of using a servo motor? High precision Low torque Expensive Low speed Hint 9). Which component is used to amplify the electrical signals sent to the servo motor? Encoder Gearbox Transistor Capacitor Hint Read more about Torque Converter 10). What is the purpose of a gearbox in a servo motor system? To provide feedback To reduce speed To increase motor size To convert AC to DC Hint 11). The resolution of a servo motor refers to ________________? Its ability to handle heavy loads The number of rotations per minute The smallest achievable movement increment The maximum temperature it can withstand Hint 12). Which type of servo motor is best suited for applications requiring continuous rotation? AC servo motor DC servo motor Stepper motor None of the above Hint 13). What is the primary advantage of a closed-loop servo system over an open-loop system? Lower cost Higher torque Better accuracy and control Simplicity in design Hint 14). Which component of a servo motor system is responsible for supplying power to the motor? Encoder Controller Power supply Gearbox Hint 15). What type of signal does a servo motor's controller typically receive? Analog Digital Mechanical Pneumatic Hint 16).Speed is measured in terms of? Meters per seconds Meters Centimeters Farads Hint 17). The "dead-band" in a servo motor control system refers to ____________________? The region around the target position where no motion occurs A fault in the encoder feedback The motor's inability to rotate continuously Excessive heat generated during operation Hint 18). Which type of servo motor control method is commonly used for robotics and automation? Open-loop control Closed-loop control Analog control PWM control Hint 19). Which factor should be considered when selecting a servo motor for an application? Input voltage Ambient temperature Output power Number of gears Hint 20). What is the primary advantage of using a brushless DC (BLDC) servo motor? Lower cost Higher efficiency Simplicity in control Suitable for high-speed applications Hint Read more about DC servo motor 21). In a PID controller, how is the control output calculated from the error signal? Summation of all three terms (P + I + D) Only the proportional term (P) The weighted sum of the three terms (kP * P + kI * I + kD * D) Only the integral term (I) Hint 22). Which term describes the difference between the desired position and the actual position in a servo motor system? Error Latency Inertia Efficiency Hint 23). What year was the first servo motor invented? 1873 1930 1955 1982 Hint 24). The initial application of servo motors was primarily in which field? Robotics Automotive Telecommunications Military Hint 25). Which of the following is not a type of servo motor? AC Servo Motor DC Servo Motor Stepper Motor Synchronous Servo Motor Hint Read more about Stepper Motor Servo Motor MCQ for Quiz 26). Who invented the first practical servo motor? Nikola Tesla Thomas Edison William Shockley Elmer Sperry Hint 27). What is the primary difference between a servo motor and a regular DC motor? Speed control Positional control Torque capacity Power efficiency Hint 28). Which component in a servo motor is responsible for providing feedback to maintain position accuracy? Gearbox Encoder Commutator Capacitor Hint 29). The term “servomechanism” is derived from two words: “servo” and “mechanism.” What does “servo” mean? Speed Control Precision Power Hint 30). Which industrial revolution saw a significant advancement in servo motor technology? First Industrial Revolution Second Industrial Revolution Third Industrial Revolution Fourth Industrial Revolution Hint 31). The pulse width modulation technique is commonly used in servo motors for ___________________? Speed control Direction control Position control Torque control Hint 32). The concept of a servo mechanism dates back to which ancient civilization? Egyptian civilization Greek civilization Roman civilization Chinese civilization Hint 33). Which type of servo motor is more suitable for high-speed applications? AC Servo Motor DC Servo Motor Stepper Motor Brushless DC Servo Motor Hint 34). Which of the following is a common cause of servo motor failure? Overheating Insufficient voltage Low humidity Excessive lubrication Hint 35). The resolution of a servo motor’s encoder is an indication of its __________________? Speed Torque Positional accuracy Power consumption Hint 36). What is the function of a servo motor driver (servo amplifier)? Provides mechanical power to the motor Converts electrical signals into mechanical motion Measures the motor’s temperature Amplifies and controls the electrical signals to the motor Hint 37). Which famous physicist and mathematician made significant contributions to the theory of servomechanisms? Albert Einstein Isaac Newton James Clerk Maxwell Werner Heisenberg Hint 38). The “deadband” in a servo system refers to _______________? The area where the motor operates most efficiently The range of input signals that do not produce any motor movement The range of input signals that do not produce any motor movement The maximum torque capacity of the motor Hint 39). Which servo motor technology is known for its ability to eliminate the need for brushes and commutators? AC Servo Motor Brushless DC Servo Motor Synchronous Servo Motor Stepper Motor Hint 40). The concept of feedback control in servo systems was formalized in the early __________________? 1600s 1700s 1800s 1900s Hint 41). What is the primary advantage of a closed-loop servo system compared to an open-loop system? Lower cost Simplicity of design Higher accuracy and stability Higher torque output Hint 42). Which of the following industries was an early adopter of servo motor technology? Oil and gas Textile Agriculture Printing Hint 43). Which equation represents the relationship between the rotational speed (ω) of a servo motor and the number of poles (P) in the motor? ω = 60 / P ω = P / 60 ω = 2 * π * P ω = P / (2 * π) Hint 44). A servo motor has a gear ratio of 1:5 and an output shaft speed of 500 RPM. What is the speed of the motor’s rotor? 2500 RPM 100 RPM 25 RPM 2000 RPM Hint 45). Which equation represents the relationship between torque (T) and angular acceleration (α) of a servo motor? T = α / r T = α * r T = r / α T = I * α Hint 46). A servo motor requires 2 milliseconds to move from 90 degrees to 180 degrees. What is its angular velocity? 90 degrees/ms 180 degrees/ms 45 degrees/ms 360 degrees/ms Hint 47). If the feedback signal of a servo motor indicates an error between the desired position and the current position, what control action is commonly used to minimize the error? Differentiation Integration Propagation Feedback Hint 48). Which of the following is a unique feature of coreless DC servo motors? High torque ripple High cogging torque Low inertia Low power efficiency Hint 49). The armature winding in a coreless DC servo motor is typically wound on a ____________________? Steel laminated core Solid iron core Copper coil Hollow cylindrical tube Hint 50). Which of the following is a significant advantage of coreless DC servo motors? High cost Low torque density Low speed response Smooth operation at low speeds Hint Servo Motor Questions for Interviews 51). What is the primary drawback of coreless DC servo motors? Low efficiency High cogging torque Limited speed range Large size Hint 52). Which of the following types of feedback devices is commonly used in coreless DC servo motors for closed-loop control? Tachometer Resolver Potentiometer Hall effect sensor Hint 53). In a coreless DC servo motor, the absence of an iron core reduces _____________________? Magnetic losses Copper losses Mechanical losses Hysteresis losses Hint 54). Which of the following is a suitable application for a coreless DC servo motor? Heavy-duty industrial conveyor belts Precision robotic arms Home ceiling fans Household blenders Hint 55). The rotor of a coreless DC servo motor is typically made of ____________________? Copper coils Permanent magnets Steel laminations Aluminum alloy Hint 56). What is the basic principle behind the operation of a DC servo motor? Electromagnetic induction Faraday’s law of electromagnetic induction Ampere’s law Biot-Savart law Hint 57). In a DC servo motor, the armature current is directly proportional to ____________________? Armature voltage Armature resistance Back EMF Magnetic flux Hint 58). The torque produced by a DC servo motor is directly proportional to ___________________? Armature current Back EMF Armature resistance Load inertia Hint 59). Which equation represents the relationship between back EMF € and armature voltage (V) in a DC servo motor? E = V + Ia * Ra E = V – Ia * Ra E = V / (Ia * Ra) E = V * (Ia * Ra) Hint 60). What is the role of a commutator in a DC servo motor? It controls the motor’s speed. It provides mechanical stability to the motor It reverses the direction of current flow in the armature windings It generates the back EMF Hint 61). What happens to the back EMF of a DC servo motor as its speed increases? Back EMF decreases Back EMF remains constant Back EMF increases Back EMF fluctuates Hint 62). The armature reaction in a DC servo motor refers to the effect of ____________________? Back EMF on the armature Armature current on the commutator Armature current on the magnetic field Load torque on the motor shaft Hint 63). Which equation represents the relationship between motor speed (N) and back EMF € in a DC servo motor? N = E / Ra N = E * Ra N = E / (Ia * Ra) N = E / (Ia * Ra) Hint 64). What is the primary function of the field windings in a DC servo motor? To generate mechanical torque To produce back EMF To create a magnetic field To control the motor’s commutation Hint 65). The torque-speed characteristic of a DC servo motor is typically represented by a __________________? Linear curve Parabolic curve Hyperbolic curve Exponential curve Hint 66). What is the primary function of a Harmonic Drive in a servo motor system? Amplification of torque Speed reduction Precision positioning Current regulation Hint 67). Harmonic Drive gears are known for their high __________________? Backlash Efficiency Speed Input voltage Hint 68). In a Harmonic Drive, the wave generator is responsible for ____________________? Generating sinusoidal waves Generating harmonic waves Controlling the motor’s position Providing mechanical advantage Hint 69). The Harmonic Drive was invented by ___________________? Albert Einstein Benjamin Franklin C. Walton Musser Nikola Tesla Hint 70). Which type of Harmonic Drive uses an elliptical wave generator? Wave Harmonic Drive Flex Wave Harmonic Drive Strain Wave Harmonic Drive Circular Harmonic Drive Hint 71). The stiffness of a Harmonic Drive is primarily dependent on _________________? The gear ratio The materials used The size of the motor The input voltage Hint 72). What is the typical range of gear ratios offered by Harmonic Drive systems? 5:1 to 20:1 50:1 to 100:1 200:1 to 400:1 1000:1 to 2000:1 Hint 73). Harmonic Drive gears are commonly used in applications that require ___________________? High torque and precision High speed and low torque Low precision and low speed Low voltage and high efficiency Hint 74). Which component is responsible for torque transmission in a Harmonic Drive? Flex spline Wave generator Circular spline Harmonic drive belt Hint 75). What type of motion can be achieved using a Harmonic Drive? Linear motion only Rotational motion only Both linear and rotational motion Lateral motion Hint Servo Motor MCQ for Exams 76). The main advantage of a Harmonic Drive over traditional gear systems is its ____________________? Low cost Simplicity Backlash-free operation Compact size Hint 77). In a Harmonic Drive system, the phase difference between the wave generator and flex spline results in ____________________? Backlash Noise Smooth motion Mechanical advantage Hint 78). The gear ratio of a Harmonic Drive system is determined by the ____________________? Number of teeth on the circular spline Number of teeth on the flex spline Distance between wave generator and flex spline Material used in the wave generator Hint 79). What type of bearing is commonly used in Harmonic Drive systems? Ball bearing Tapered roller bearing Needle roller bearing Cross roller bearing Hint 80). Harmonic Drive systems are widely used in which of the following industries? Food and beverage Automotive Aerospace All of the above Hint 81). What is the purpose of a Harmonic Drive coupling in a servo motor setup? To connect the motor to the load To reduce backlash To increase motor speed To generate harmonic waves Hint 82). Which type of Harmonic Drive is more suitable for high-torque applications? Wave Harmonic Drive Flex Wave Harmonic Drive Strain Wave Harmonic Drive Circular Harmonic Drive Hint 83). The torque output of a Harmonic Drive system depends on the ___________________? Voltage supplied to the motor Number of teeth on the circular spline Speed of the wave generator Size of the flex spline Hint 84). What is the primary limitation of Harmonic Drive systems? High cost Low efficiency Limited speed range High maintenance Hint 85). Harmonic Drive gears are known for their excellent ____________________? Energy efficiency Thermal conductivity Corrosion resistance Frictional losses Hint 86). The term “Harmonic Drive” refers to __________________? The type of motor used A specific type of harmonic wave The harmonic distortion produced Hint 87). The primary application of a Harmonic Drive is in _________________? Continuous rotation systems Linear motion systems Robotic arms and manipulators Conveyors and belts Hint 88). In a Harmonic Drive system, what is the effect of increasing the wave generator speed? Increases backlash Decreases torque output Increases precision Decreases gear ratio Hint 89). Harmonic Drive systems are commonly used in robotic applications due to their __________________? High cost-effectiveness High speed capabilities High precision and compact size Low torque output Hint 90). What is the typical efficiency range of Harmonic Drive systems? 50% to 60% 70% to 80% 90% to 95% 100% Hint 91). The primary advantage of a Harmonic Drive in robotic applications is its ability to _____________________? Perform linear motion Perform rotational motion Maintain positional accuracy Withstand high temperatures Hint 92). Which material is commonly used for the flex spline in a Harmonic Drive system? Stainless steel Aluminum Brass Plastic Hint 93). What is the primary factor that limits the maximum torque capacity of a Harmonic Drive? Wave generator size Flex spline size Circular spline size Gear ratio Hint 94). Harmonic Drive gears are classified as_________________? Planetary gears Cycloidal gears Epicyclic gears Helical gears Hint 95). The Harmonic Drive system was initially developed for use in _______________? Military applications Space exploration Industrial automation Hint 96). In a PID controller, the proportional term is responsible for ____________________? Reducing steady-state error Eliminating oscillations Predicting future errors Integrating the error over time Hint 97). The integral term in a PID controller is used to ________________? Reduce overshoot and oscillations Improve system stability and eliminate steady-state error Predict future errors and dampen system response Provide a derivative of the error signal Hint 98). The differential term in a PID controller is used to ___________________? Reduce the impact of disturbances and noise Integrate the error signal over time Predict future errors and provide anticipatory control Eliminate steady-state error Hint 99). Which term of the PID controller is responsible for anticipating future errors and providing anticipatory control? Proportional (P) Integral (I) Differential (D) Proportional and Integral (PI) Hint 100). In a PID controller, how is the control output calculated from the error signal? Summation of all three terms (P + I + D) The weighted sum of the three terms (kP * P + kI * I + kD * D) Only the integral term (I) Hint For More MCQs Slip Ring Motor MCQs Three Phase Induction Motor MCQs Switched Reluctance Motor MCQs Reluctance Motor MCQs Induction Motor MCQs Repulsion Motor MCQs Time's up
