Sending velocity commands in Drone Programming - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to send a forward velocity command to the drone.

Drone Programming

drone.send_velocity([1], 0, 0)

Drag options to blanks, or click blank then click option'

A-1.0

B0

C1.0

DNone

Attempts:

3 left

💡 Hint

Common Mistakes

Using 0 means no forward movement.

Using None causes an error.

The first parameter is the forward velocity in meters per second. Using 1.0 moves the drone forward.

2fill in blank

medium

Complete the code to send a velocity command that moves the drone upward.

Drone Programming

drone.send_velocity(0, 0, [1])

Drag options to blanks, or click blank then click option'

A1.0

B-1.0

C0

DNone

Attempts:

3 left

💡 Hint

Common Mistakes

Using negative value moves drone down.

Using zero means no vertical movement.

The third parameter controls vertical velocity. Positive 1.0 moves the drone up.

3fill in blank

hard

Fix the error in the code to send a velocity command moving left.

Drone Programming

drone.send_velocity(0, [1], 0)

Drag options to blanks, or click blank then click option'

A-1.0

B1.0

C0

DNone

Attempts:

3 left

💡 Hint

Common Mistakes

Using positive value moves right instead of left.

Using None causes error.

The second parameter controls left/right velocity. Negative value moves left.

4fill in blank

hard

Fill both blanks to send a velocity command moving forward and upward.

Drone Programming

drone.send_velocity([1], 0, [2])

Drag options to blanks, or click blank then click option'

A1.0

B0

C-1.0

DNone

Attempts:

3 left

💡 Hint

Common Mistakes

Using zero for either velocity means no movement in that direction.

Using None causes errors.

Use 1.0 for forward (x) and 1.0 for upward (z) velocity to move diagonally up and forward.

5fill in blank

hard

Fill all three blanks to send a velocity command moving backward, right, and downward.

Drone Programming

drone.send_velocity([1], [2], [3])

Drag options to blanks, or click blank then click option'

A-1.0

B1.0

C0

DNone

Attempts:

3 left

💡 Hint

Common Mistakes

Mixing up positive and negative signs.

Using None causes errors.

Backward is negative x velocity, right is positive y velocity, downward is negative z velocity.

Practice

1. What does sending a velocity command to a drone usually control?
send_velocity(x_speed, y_speed, z_speed, duration)

easy

A. The drone's battery level

B. The speed and direction the drone moves in each axis

C. The drone's camera angle

D. The drone's GPS coordinates

Solution

1. Step 1: Understand velocity command parameters

   The parameters x_speed, y_speed, and z_speed represent how fast the drone moves along each axis.

2. Step 2: Connect parameters to drone movement

   These speeds control the drone's direction and speed, while duration controls how long it moves.

3. Final Answer:

   The speed and direction the drone moves in each axis -> Option B

4. Quick Check:

   Velocity commands = speed and direction control [OK]

Hint: Velocity commands set speed and direction, not camera or battery [OK]

Common Mistakes:

• Confusing velocity with camera control
• Thinking velocity sets GPS location directly
• Assuming velocity changes battery level

2. Which of the following is the correct syntax to send a velocity command moving the drone forward at 2 m/s for 5 seconds?

easy

A. send_velocity(5, 0, 0, 2)

B. send_velocity(0, 2, 0, 5)

C. send_velocity(0, 0, 2, 5)

D. send_velocity(2, 0, 0, 5)

Solution

1. Step 1: Identify forward direction axis

   Forward movement is usually along the X-axis, so x_speed should be 2.

2. Step 2: Check duration and other speeds

   Y and Z speeds are zero, duration is 5 seconds, matching the command.

3. Final Answer:

   send_velocity(2, 0, 0, 5) -> Option D

4. Quick Check:

   X-axis speed = 2, duration = 5 [OK]

Hint: Forward speed is X-axis; duration is last parameter [OK]

Common Mistakes:

• Mixing up X and Y axes
• Putting duration in wrong position
• Setting speed on wrong axis

3. What will be the drone's movement after running this code?

send_velocity(0, -3, 0, 4)

medium

A. The drone moves left at 3 m/s for 4 seconds

B. The drone moves backward at 3 m/s for 4 seconds

C. The drone moves right at 3 m/s for 4 seconds

D. The drone moves upward at 3 m/s for 4 seconds

Solution

1. Step 1: Identify axis for Y speed

   The Y-axis controls left-right movement; negative means left.

2. Step 2: Interpret speed and duration

   Speed is 3 m/s left for 4 seconds, no movement on X or Z axes.

3. Final Answer:

   The drone moves left at 3 m/s for 4 seconds -> Option A

4. Quick Check:

   Negative Y speed = left movement [OK]

Hint: Negative Y speed means left movement [OK]

Common Mistakes:

• Confusing negative Y with backward
• Mixing Y and Z axes
• Assuming negative means right

4. Identify the error in this velocity command code:

send_velocity(1, 0, 0)

medium

A. Missing duration parameter

B. Wrong order of speed parameters

C. Negative speed value not allowed

D. Extra parameter included

Solution

1. Step 1: Check function parameters

   The function requires four parameters: x_speed, y_speed, z_speed, and duration.

2. Step 2: Identify missing parameter

   Only three parameters are given; duration is missing, causing an error.

3. Final Answer:

   Missing duration parameter -> Option A

4. Quick Check:

   Duration required as 4th parameter [OK]

Hint: Velocity commands need 4 parameters: x, y, z, duration [OK]

Common Mistakes:

• Forgetting duration parameter
• Swapping speed and duration order
• Using negative duration

5. You want the drone to move diagonally upward forward at 1 m/s on X and Z axes for 3 seconds, but keep Y speed zero. Which command is correct?

hard

A. send_velocity(1, 1, 0, 3)

B. send_velocity(0, 1, 1, 3)

C. send_velocity(1, 0, 1, 3)

D. send_velocity(1, 0, 0, 1)

Solution

1. Step 1: Assign speeds to correct axes

   X speed = 1 (forward), Y speed = 0 (no sideways), Z speed = 1 (upward).

2. Step 2: Check duration matches requirement

   Duration is 3 seconds, matching the problem statement.

3. Final Answer:

   send_velocity(1, 0, 1, 3) -> Option C

4. Quick Check:

   X=1, Y=0, Z=1, duration=3 [OK]

Hint: Set speeds on X and Z, zero on Y, duration last [OK]

Common Mistakes:

• Mixing Y and Z speeds
• Wrong duration value
• Setting zero on wrong axis