Axes of rotation (roll, pitch, yaw) in Drone Programming - Practice Problems & Coding Challenges

Challenge - 5 Problems

❓ Predict Output

intermediate

Output of combined roll and pitch rotations

Consider a drone starting with orientation angles roll=0°, pitch=0°, yaw=0°. The drone applies a roll of 30° followed by a pitch of 45°. What is the final pitch angle after these rotations?

Drone Programming

roll = 0
pitch = 0
yaw = 0

# Apply roll
roll += 30
# Apply pitch
pitch += 45

print(pitch)

A 0

B 30

C 45

D 75

💡 Hint

Roll changes the rotation around the front-to-back axis, pitch changes rotation around the side-to-side axis. They add independently here.

Roll and pitch are rotations around different axes. Applying roll does not change pitch. After applying pitch of 45°, the pitch angle is 45°.

🧠 Conceptual

intermediate

Identifying axis of yaw rotation

Which axis does the yaw rotation occur around in a drone's coordinate system?

A Front-to-back axis

B Vertical axis

C Side-to-side axis

D Diagonal axis

💡 Hint

Yaw turns the drone left or right, like turning your head.

Yaw is rotation around the vertical axis, which points up from the drone. This rotation changes the drone's heading direction.

❓ Predict Output

advanced

Result of sequential yaw and roll rotations

A drone starts with roll=0°, pitch=0°, yaw=0°. It first applies a yaw of 90°, then a roll of 90°. What is the final roll angle?

Drone Programming

roll = 0
pitch = 0
yaw = 0

yaw += 90
roll += 90

print(roll)

A 270

B 0

C 180

D 90

💡 Hint

Roll and yaw rotations are around different axes and add independently here.

Yaw changes heading but does not affect roll angle. After applying roll of 90°, the roll angle is 90°.

🔧 Debug

advanced

Identify the error in pitch update code

What error does the following code produce?

pitch = 0
pitch = pitch + '30'
print(pitch)

A TypeError: unsupported operand type(s) for +: 'int' and 'str'

B SyntaxError: invalid syntax

C NameError: name 'pitch' is not defined

D No error, prints 30

💡 Hint

Check the types of values being added.

The code tries to add an integer (pitch) and a string ('30'), which causes a TypeError.

🚀 Application

expert

Calculate final orientation after roll, pitch, yaw sequence

A drone starts at roll=0°, pitch=0°, yaw=0°. It applies these rotations in order: roll=45°, pitch=30°, yaw=60°. What is the final yaw angle?

Drone Programming

roll = 0
pitch = 0
yaw = 0

roll += 45
pitch += 30
yaw += 60

print(yaw)

A 60

B 30

C 45

D 0

💡 Hint

Each rotation changes its own axis angle independently here.

Yaw is updated last by adding 60°. The final yaw angle is 60°.

Practice

1.

Which axis controls the drone's rotation that tilts it side to side?

easy

A. Pitch

B. Roll

C. Yaw

D. Throttle

Solution

1. Step 1: Understand the meaning of roll

   Roll is the rotation that tilts the drone left or right, like tipping side to side.

2. Step 2: Match roll to the axis

   Since roll controls side to side tilt, it matches the question.

3. Final Answer:

   Roll -> Option B

4. Quick Check:

   Side to side tilt = Roll [OK]

Hint: Roll = side tilt, Pitch = forward/back, Yaw = turn [OK]

Common Mistakes:

• Confusing pitch with roll
• Thinking yaw controls tilt
• Selecting throttle which controls speed

2.

Which of the following is the correct way to set the yaw angle to 45 degrees in a drone control program?

drone.set_yaw(____)

easy

A. "45"

B. set_yaw(45)

C. yaw = 45

D. 45

Solution

1. Step 1: Identify the correct argument type

   The method expects a number for the angle, so 45 without quotes is correct.

2. Step 2: Check the method call syntax

   drone.set_yaw(45) correctly calls the method with the number 45.

3. Final Answer:

   45 -> Option D

4. Quick Check:

   Number angle without quotes = 45 [OK]

Hint: Use numbers for angles, no quotes needed [OK]

Common Mistakes:

• Using quotes around numbers
• Assigning inside method call
• Calling method without object prefix

3.

What will be the output of this code snippet controlling drone rotation?

roll = 10
pitch = -5
yaw = 90
print(f"Roll: {roll}, Pitch: {pitch}, Yaw: {yaw}")

medium

A. Roll: 10, Pitch: -5, Yaw: 90

B. Roll: 10, Pitch: 5, Yaw: 90

C. Roll: 0, Pitch: -5, Yaw: 90

D. Error: yaw not defined

Solution

1. Step 1: Check variable assignments

   roll is 10, pitch is -5, yaw is 90 as assigned.

2. Step 2: Evaluate the print statement

   The f-string prints the values exactly as assigned.

3. Final Answer:

   Roll: 10, Pitch: -5, Yaw: 90 -> Option A

4. Quick Check:

   Print variables as assigned = Roll: 10, Pitch: -5, Yaw: 90 [OK]

Hint: Print variables exactly as assigned in f-string [OK]

Common Mistakes:

• Ignoring negative sign in pitch
• Assuming yaw is zero
• Mistyping variable names

4.

Find the error in this code that sets drone rotation angles:

drone.roll = 15
pitch = 20
drone.yaw = 45
print(f"Roll: {drone.roll}, Pitch: {pitch}, Yaw: {yaw}")

medium

A. roll should be assigned with drone.set_roll()

B. pitch should be drone.pitch

C. Variable yaw is not defined before print

D. print statement syntax is incorrect

Solution

1. Step 1: Check variable definitions

   roll and yaw are accessed as drone.roll and drone.yaw, pitch is a separate variable.

2. Step 2: Identify undefined variable in print

   yaw is used without drone prefix and not defined as variable, causing error.

3. Final Answer:

   Variable yaw is not defined before print -> Option C

4. Quick Check:

   Undefined variable in print = yaw [OK]

Hint: Check all variables used in print are defined [OK]

Common Mistakes:

• Assuming yaw variable exists without prefix
• Confusing pitch variable scope
• Thinking print syntax is wrong

5.

You want to program a drone to tilt forward by 30 degrees, roll right by 15 degrees, and turn left by 90 degrees. Which code snippet correctly sets these rotations?

Option A:
drone.set_pitch(30)
drone.set_roll(15)
drone.set_yaw(-90)

Option B:
drone.set_pitch(-30)
drone.set_roll(-15)
drone.set_yaw(90)

Option C:
drone.set_pitch(30)
drone.set_roll(-15)
drone.set_yaw(90)

Option D:
drone.set_pitch(-30)
drone.set_roll(15)
drone.set_yaw(-90)

hard

A. Pitch 30, Roll 15, Yaw -90

B. Pitch -30, Roll -15, Yaw 90

C. Pitch 30, Roll -15, Yaw 90

D. Pitch -30, Roll 15, Yaw -90

Solution

1. Step 1: Understand direction signs

   Forward tilt means positive pitch (30), roll right means positive roll (15), turn left means negative yaw (-90).

2. Step 2: Match signs to code options

   Pitch 30, Roll 15, Yaw -90 matches pitch=30, roll=15, yaw=-90 correctly.

3. Final Answer:

   Pitch 30, Roll 15, Yaw -90 -> Option A

4. Quick Check:

   Forward=+pitch, Right=+roll, Left=-yaw [OK]

Hint: Positive pitch forward, positive roll right, negative yaw left [OK]

Common Mistakes:

• Mixing positive/negative signs for directions
• Confusing roll and pitch directions
• Assuming yaw left is positive