Receiving telemetry data in Drone Programming - Mini Project: Build & Apply

Receiving telemetry data

📖 Scenario: You are programming a drone that sends telemetry data about its position and battery level. You want to receive this data and process it step-by-step.

🎯 Goal: Build a program that receives telemetry data as a dictionary, sets a battery warning threshold, filters the telemetry data to find values below the threshold, and then prints the warnings.

📋 What You'll Learn

Create a dictionary called telemetry_data with keys 'altitude', 'speed', and 'battery' and values 120, 45, and 15 respectively.

Create a variable called battery_warning_level and set it to 20.

Use a dictionary comprehension called warnings to include only telemetry items where the value is less than battery_warning_level.

Print the warnings dictionary.

💡 Why This Matters

🌍 Real World

Drones send telemetry data to ground stations to monitor flight status and safety.

💼 Career

Understanding how to receive and filter telemetry data is important for drone software developers and engineers working with real-time sensor data.

1

Create telemetry data dictionary

Create a dictionary called telemetry_data with these exact entries: 'altitude': 120, 'speed': 45, and 'battery': 15.

Drone Programming

# Create the telemetry_data dictionary with altitude, speed, and battery
# Your code here

Hint

Use curly braces {} to create a dictionary with the given keys and values.

2

Set battery warning level

Create a variable called battery_warning_level and set it to 20.

Drone Programming

telemetry_data = {'altitude': 120, 'speed': 45, 'battery': 15}
# Set battery_warning_level to 20
# Your code here

Hint

Just assign the number 20 to the variable battery_warning_level.

3

Filter telemetry warnings

Use a dictionary comprehension called warnings to include only items from telemetry_data where the value is less than battery_warning_level.

Drone Programming

telemetry_data = {'altitude': 120, 'speed': 45, 'battery': 15}
battery_warning_level = 20
# Create warnings dictionary with items below battery_warning_level
# Your code here

Hint

Use {key: value for key, value in telemetry_data.items() if value < battery_warning_level}.

4

Print warnings

Print the warnings dictionary.

Drone Programming

telemetry_data = {'altitude': 120, 'speed': 45, 'battery': 15}
battery_warning_level = 20
warnings = {key: value for key, value in telemetry_data.items() if value < battery_warning_level}
# Print the warnings dictionary
# Your code here

Hint

Use print(warnings) to show the filtered dictionary.

Practice

1.

What does telemetry data from a drone usually include?

easy

A. Information about the drone's position and battery status

B. The drone's color and shape

C. The pilot's personal details

D. The weather forecast for the day

Solution

1. Step 1: Understand telemetry data purpose

   Telemetry data provides real-time information about the drone's current state.

2. Step 2: Identify typical telemetry contents

   Common telemetry includes position coordinates and battery level, not unrelated info like color or weather.

3. Final Answer:

   Information about the drone's position and battery status -> Option A

4. Quick Check:

   Telemetry = position + battery [OK]

Hint: Telemetry means drone status info like position and battery [OK]

Common Mistakes:

• Confusing telemetry with unrelated data like weather
• Thinking telemetry includes pilot personal info
• Assuming telemetry is about drone appearance

2.

Which of the following is the correct way to receive telemetry data from a drone object named drone?

?

easy

A. telemetry = drone.receiveTelemetry

B. telemetry = drone.get_telemetry()

C. telemetry = get_telemetry(drone)

D. telemetry = drone.telemetry()

Solution

1. Step 1: Identify method call syntax

   To call a method on an object, use dot notation with parentheses: object.method()

2. Step 2: Match method name exactly

   The correct method is get_telemetry(), so drone.get_telemetry() is correct.

3. Final Answer:

   telemetry = drone.get_telemetry() -> Option B

4. Quick Check:

   Method call syntax = drone.get_telemetry() [OK]

Hint: Use dot and parentheses to call get_telemetry() method [OK]

Common Mistakes:

• Missing parentheses when calling method
• Using wrong method name or syntax
• Trying to call method without object

3.

What will be the output of this code snippet?

drone = Drone()
telemetry = drone.get_telemetry()
print(telemetry['battery'])

Assume get_telemetry() returns {'position': (10, 20), 'battery': 85}.

medium

A. 10

B. (10, 20)

C. Error

D. 85

Solution

1. Step 1: Understand returned telemetry dictionary

   The telemetry dictionary has keys 'position' and 'battery' with values (10, 20) and 85 respectively.

2. Step 2: Access the 'battery' key value

   Printing telemetry['battery'] outputs 85, the battery percentage.

3. Final Answer:

   85 -> Option D

4. Quick Check:

   telemetry['battery'] = 85 [OK]

Hint: Access dictionary key 'battery' to get battery level [OK]

Common Mistakes:

• Confusing 'position' with 'battery' key
• Trying to print telemetry without key
• Assuming output is a tuple instead of number

4.

Find the error in this code that tries to print the drone's position from telemetry data:

telemetry = drone.get_telemetry()
print(telemetry.position)

medium

A. Accessing dictionary key with dot notation causes error

B. telemetry is not defined

C. Missing parentheses in get_telemetry call

D. print statement syntax is wrong

Solution

1. Step 1: Check how telemetry data is accessed

   Telemetry is a dictionary, so keys must be accessed with square brackets, not dot notation.

2. Step 2: Identify the error cause

   Using telemetry.position causes an AttributeError because dictionaries don't support dot notation.

3. Final Answer:

   Accessing dictionary key with dot notation causes error -> Option A

4. Quick Check:

   Dictionary keys need brackets, not dots [OK]

Hint: Use brackets [] to access dictionary keys, not dot . [OK]

Common Mistakes:

• Using dot notation on dictionary keys
• Forgetting parentheses on method call
• Assuming telemetry is an object with attributes

5.

You want to check if the drone's battery is below 20% and print a warning. Which code correctly does this using telemetry data?

telemetry = drone.get_telemetry()
?

hard

A. if telemetry['battery'] > 20:
print('Warning: Low battery!')

B. if telemetry.battery < 20:
print('Warning: Low battery!')

C. if telemetry['battery'] < 20:
print('Warning: Low battery!')

D. if drone.battery < 20:
print('Warning: Low battery!')

Solution

1. Step 1: Access battery level correctly from telemetry

   Telemetry is a dictionary, so use square brackets: telemetry['battery'].

2. Step 2: Write condition to check if battery is below 20

   The condition should be < 20 to detect low battery and print warning.

3. Final Answer:

   if telemetry['battery'] < 20: print('Warning: Low battery!') -> Option C

4. Quick Check:

   Check battery < 20 with brackets [OK]

Hint: Use telemetry['battery'] < 20 to check low battery [OK]

Common Mistakes:

• Using dot notation to access battery
• Checking battery > 20 instead of < 20
• Accessing battery directly from drone object