How motor speed controls movement in Drone Programming - Interactive Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to set the motor speed to 100.

Drone Programming

motor.setSpeed([1])

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

A100

Bspeed

CmotorSpeed

D0

Attempts:

3 left

💡 Hint

Common Mistakes

Using a variable name instead of a number.

Setting speed to 0 which stops the motor.

The motor speed must be set to 100 to make the drone move at full speed.

2fill in blank

medium

Complete the code to increase the motor speed by 10.

Drone Programming

motor.setSpeed(motor.getSpeed() [1] 10)

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

A-

B*

C/

D+

Attempts:

3 left

💡 Hint

Common Mistakes

Using '-' which decreases speed.

Using '*' or '/' which changes speed incorrectly.

Adding 10 to the current speed increases the motor speed.

3fill in blank

hard

Fix the error in the code to correctly set the motor speed.

Drone Programming

motor.setSpeed([1])

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

Aspeed - 10

Bspeed + 10

Cspeed * 10

Dspeed / 10

Attempts:

3 left

💡 Hint

Common Mistakes

Using subtraction or multiplication instead of addition.

Dividing speed which reduces it.

To increase speed by 10, add 10 to the current speed variable.

4fill in blank

hard

Fill both blanks to create a dictionary of motor speeds for each motor where speed is above 50.

Drone Programming

motor_speeds = {motor: [1] for motor, speed in motors.items() if speed [2] 50}

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

Aspeed

Bmotor

C>

D<

Attempts:

3 left

💡 Hint

Common Mistakes

Using motor as value instead of speed.

Using '<' which selects speeds below 50.

The dictionary stores speeds for motors where speed is greater than 50.

5fill in blank

hard

Fill all three blanks to create a dictionary with motor names in uppercase as keys, speeds as values, and only include motors with speed above 60.

Drone Programming

motor_speeds = [1]: [2] for motor, speed in motors.items() if speed [3] 60

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

Amotor.upper()

Bspeed

C>

Dmotor.lower()

Attempts:

3 left

💡 Hint

Common Mistakes

Using motor.lower() instead of upper().

Using '<' which filters wrong speeds.

The keys are motor names in uppercase, values are speeds, and only motors with speed greater than 60 are included.

Practice

1. What happens when all four drone motors run at the same speed?

easy

A. The drone spins rapidly in place

B. The drone hovers or moves straight up or down

C. The drone moves sideways

D. The drone immediately lands

Solution

1. Step 1: Understand motor speed effect on lift

   When all motors run at the same speed, they produce equal lift, balancing the drone.

2. Step 2: Determine movement from equal lift

   Equal lift means the drone either stays in place (hover) or moves straight up/down if speed changes.

3. Final Answer:

   The drone hovers or moves straight up or down -> Option B

4. Quick Check:

   Equal motor speeds = hover/up/down [OK]

Hint: Same speed on all motors means hover or vertical move [OK]

Common Mistakes:

• Thinking equal speeds cause spinning
• Assuming sideways movement with equal speeds
• Confusing motor speed with drone landing

2. Which of the following is the correct way to set motor speeds in code to make the drone hover?

easy

A. setMotorSpeeds(100, 90, 100, 90);

B. setMotorSpeeds(0, 0, 0, 0);

C. setMotorSpeeds(100, 100, 100, 100);

D. setMotorSpeeds(100, 110, 90, 100);

Solution

1. Step 1: Identify equal motor speeds for hover

   Hover requires all motors to run at the same speed to balance lift.

2. Step 2: Check each option for equal speeds

   Only setMotorSpeeds(100, 100, 100, 100); has all motors set to 100, equal speeds for hover.

3. Final Answer:

   setMotorSpeeds(100, 100, 100, 100); -> Option C

4. Quick Check:

   Equal speeds in code = hover [OK]

Hint: Equal values in all motor speed parameters mean hover [OK]

Common Mistakes:

• Using different speeds thinking it still hovers
• Setting all speeds to zero which stops motors
• Mixing up parameter order

3. Given this code snippet:

setMotorSpeeds(120, 100, 120, 100);

What movement will the drone most likely perform?

medium

A. Move forward

B. Hover in place

C. Tilt sideways and move right

D. Rotate clockwise

Solution

1. Step 1: Analyze motor speed differences

   Motors 1 and 3 run faster (120) than motors 2 and 4 (100), creating torque imbalance.

2. Step 2: Understand effect of torque imbalance

   This imbalance causes the drone to rotate (yaw) clockwise due to uneven motor speeds.

3. Final Answer:

   Rotate clockwise -> Option D

4. Quick Check:

   Unequal opposite motors speed = rotation [OK]

Hint: Faster opposite motors cause rotation [OK]

Common Mistakes:

• Assuming forward movement from speed difference
• Thinking drone hovers with different speeds
• Confusing rotation direction

4. This code is intended to make the drone move forward:

setMotorSpeeds(110, 110, 90, 90);

But the drone spins instead. What is the likely error?

medium

A. Left and right motors have different speeds causing spin

B. Front motors are slower than rear motors

C. Motors on opposite sides have same speeds causing rotation

D. All motors have equal speeds causing hover

Solution

1. Step 1: Identify motor speed pairs

   Motors 1 and 2 are 110, motors 3 and 4 are 90; left and right sides differ.

2. Step 2: Understand effect of left-right speed difference

   Different speeds on left vs right cause the drone to spin (yaw), not move forward.

3. Final Answer:

   Left and right motors have different speeds causing spin -> Option A

4. Quick Check:

   Unequal left-right speeds = spin [OK]

Hint: Left-right speed difference causes spin, not forward move [OK]

Common Mistakes:

• Thinking front-rear speed difference causes spin
• Assuming equal speeds cause spin
• Mixing motor numbering sides

5. You want the drone to tilt forward and move forward smoothly. Which motor speed setting is best?

setMotorSpeeds(95, 95, 105, 105);

Why does this work?

hard

A. Front motors slower than rear motors tilt drone forward

B. Rear motors slower than front motors tilt drone backward

C. Left motors faster than right motors cause forward tilt

D. All motors equal speed cause forward movement

Solution

1. Step 1: Identify motor speed distribution

   Motors 1 and 2 (front) run at 95, motors 3 and 4 (rear) at 105; front motors slower than rear.

2. Step 2: Understand tilt direction from speed difference

   Slower front motors provide less lift upfront, tilting the nose down for forward movement.

3. Final Answer:

   Front motors slower than rear motors tilt drone forward -> Option A

4. Quick Check:

   Slower front motors = forward tilt [OK]

Hint: Slower front motors than rear tilt drone forward [OK]

Common Mistakes:

• Thinking faster front motors tilt forward
• Confusing left-right with front-rear speeds
• Assuming equal speeds cause tilt