Unit 5: Remote controller and Autopilot - Practice Quiz

1 What is the main purpose of a drone remote controller?

2 Which remote-controller control is commonly used to change a drone's direction and altitude?

3 What does the throttle control usually change on a multirotor drone?

4 Which part of a remote controller transmits radio signals?

5 What is the primary function of a receiver on a drone?

6 Where is the radio receiver normally installed in a drone system?

7 What process connects a radio receiver with a specific remote controller?

8 What is telemetry in a drone system?

9 Which information is commonly sent through a drone telemetry system?

10 Why is telemetry useful to a drone pilot?

11 What is the main role of an autopilot system in a drone?

12 Which component is often called the brain of an autonomous drone?

13 What can an autopilot use to follow a planned route?

14 What information does an autopilot process to maintain stable flight?

15 Which internal sensor measures a drone's angular rotation rate?

16 Which internal sensor measures acceleration?

17 Which sensor uses air pressure to help estimate altitude?

18 Which external sensor provides geographic position information?

19 Which external sensor can measure the distance between a drone and an obstacle?

20 What does an optical-flow sensor help a drone detect?

21 On a Mode 2 remote controller, a pilot wants to increase altitude without intentionally changing yaw, pitch, or roll. Which input should be applied?

22 A drone responds too sharply to small stick movements near the center, but the pilot still needs full control authority at maximum stick deflection. Which transmitter adjustment is most appropriate?

23 During a preflight check, the flight controller shows only 80% input when the transmitter stick is at its maximum position. What should be checked first?

24 A receiver has two diversity antennas. How should their active sections generally be arranged to reduce signal loss caused by aircraft orientation?

25 What receiver configuration best protects a drone if the transmitter signal is lost during flight?

26 After installing a new receiver, moving the roll stick changes the flight controller's yaw input. What is the most likely cause?

27 The drone still responds normally to control inputs, but battery voltage and position stop updating on the ground station. What is the most likely problem?

28 During a long-range flight, telemetry RSSI steadily falls and packet-loss warnings appear. What is the most appropriate immediate response?

29 A telemetry system reports attitude only once per second. Why is it unsuitable for diagnosing a rapid oscillation occurring at ?

30 A drone following a straight GPS route encounters a steady crosswind. What should a functioning autopilot do to remain on the route?

31 In Stabilize mode, a drone levels itself when the sticks are centered but does not maintain altitude automatically. Why is this expected?

32 After a metal payload is installed, the autopilot reports inconsistent compass readings during its pre-arm check. What should the operator do?

33 A stationary drone reports a slowly increasing yaw rate after its electronics warm up. Which action most directly addresses this behavior?

34 Flight logs show high-frequency accelerometer noise that increases with motor speed. Which corrective action should be tried first?

35 A barometric altitude reading fluctuates whenever propeller airflow passes over the flight controller. What is the best mitigation?

36 A drone's heading changes by several degrees when high motor current flows, although its physical direction is unchanged. What is the most likely cause?

37 A drone operating between tall buildings shows sudden GPS position jumps despite tracking several satellites. Which effect most likely explains this?

38 For automatic landing close to the ground, which external sensor generally provides more precise direct height measurement than standard GPS?

39 An indoor drone using optical flow holds position over a patterned floor but drifts over a glossy, featureless floor. What is the best explanation?

40 A fixed-wing drone maintains a constant GPS ground speed while flying into stronger headwind. What should a correctly functioning airspeed sensor indicate?

41 A transmitter maps a centered stick input to pulse widths from to . It applies a symmetric deadband of and then rescales each remaining side so full stick still produces the endpoint. What pulse width should be transmitted for ?

42 A pilot applies full roll and full pitch simultaneously. The transmitter independently maps both commands to motor-mixing inputs, causing the mixed outputs to exceed their allowed range. Which treatment best preserves the requested control direction while avoiding clipping distortion?

43 A remote-control link has a transmitter EIRP of , path loss of , receiver antenna gain of , and miscellaneous losses of . If receiver sensitivity is , what is the link margin?

44 A serial RC receiver reports valid channel values for several frames after losing its RF link, but it also asserts a failsafe status flag. How should a safety-critical autopilot interpret these frames?

45 A diversity receiver switches antennas whenever the alternate antenna's RSSI is momentarily higher. During flight, this produces frequent switching and bursts of lost frames. Which modification most directly addresses the problem?

46 Eight independent PWM receiver channels update at but begin their pulses at unrelated times. An autopilot reads each channel immediately after its edge arrives. What subtle control-input problem can result compared with decoding one framed serial packet?

47 A telemetry stream uses packet sequence numbers modulo . The last accepted number was , followed by packets numbered and . Assuming packets arrive in order, how many packets were lost before packet ?

48 A half-duplex telemetry radio provides a raw rate of . Protocol overhead consumes of transmitted bits, and the air-time schedule assigns to downlink. What is the maximum downlink payload rate under continuous loading?

49 A ground station receives a delayed position packet after a newer packet because the radio retransmitted it. Which design best prevents the displayed vehicle position from moving backward in time?

50 In a cascaded multirotor controller, the outer attitude loop produces a desired angular rate, while the inner rate loop commands torque. Why should the inner loop normally run at a substantially higher bandwidth?

51 During a strong wind, a vehicle's commanded roll torque remains beyond actuator capability, so the rate controller's integral term grows continuously. When the wind drops, the vehicle overshoots severely. Which correction is most appropriate?

52 An autopilot's estimator reports a GNSS velocity innovation of with innovation variance . For a normalized innovation squared gate of , how should this scalar measurement be handled?

53 A fixed-wing autopilot must track a ground path in steady crosswind. Airspeed is sufficient, but commanding the aircraft nose directly along the desired ground-track bearing causes lateral drift. What should the guidance system command?

54 A stationary gyroscope has an uncompensated constant bias of . If attitude is obtained only by integrating its output, approximately how much attitude error accumulates in minutes?

55 A multirotor accelerates horizontally at while remaining level. An attitude estimator temporarily treats the accelerometer as measuring gravity alone. Approximately what false tilt angle can this assumption introduce?

56 Barometric altitude suddenly indicates a climb whenever rotor speed increases, even though GNSS and range measurements show constant altitude. Which mechanism and mitigation are most consistent with this behavior?

57 Magnetometer heading error is small with motors off but increases predictably with total motor current. Which calibration model most directly targets this effect?

58 During GNSS denial, an optical-flow sensor reports image motion in radians per second. Which additional measurement is most directly required to convert that angular flow into metric horizontal velocity over level ground?

59 A downward rangefinder measures distance along the body vertical axis while the vehicle is tilted by roll and pitch above flat terrain. Ignoring sensor offset, which expression gives vertical height?

60 Near tall reflective buildings, a GNSS receiver reports high satellite count and a plausible position, but the position repeatedly jumps by several meters. Which evidence most strongly indicates multipath rather than normal vehicle motion?