Waypoint radius and acceptance in Drone Programming - Step-by-Step Execution

Concept Flow - Waypoint radius and acceptance

Start at current position

↓

Calculate distance to waypoint

↓

Is distance <= radius?

No→Move drone closer

|Yes↓

Waypoint accepted

↓

Proceed to next waypoint or stop

The drone checks if it is within a set radius of the waypoint. If yes, it accepts the waypoint and moves on. If no, it moves closer and checks again.

Execution Sample

Drone Programming

current_pos = (0, 0)
waypoint = (5, 5)
radius = 2
while True:
    dist = distance(current_pos, waypoint)
    if dist <= radius:
        break
    current_pos = move_towards(current_pos, waypoint)

This code moves the drone towards a waypoint until it is within the acceptance radius.

Execution Table

Step	current_pos	distance to waypoint	Condition (dist <= radius)	Action	Output
1	(0, 0)	7.07	False	Move closer	Position updated
2	(1, 1)	5.66	False	Move closer	Position updated
3	(2, 2)	4.24	False	Move closer	Position updated
4	(3, 3)	2.83	False	Move closer	Position updated
5	(4, 4)	1.41	True	Accept waypoint	Exit loop
6	(4, 4)	1.41	True	Stop moving	Waypoint accepted

💡 At step 5, distance 1.41 <= radius 2, so waypoint is accepted and loop exits.

Variable Tracker

Variable	Start	After 1	After 2	After 3	After 4	After 5	Final
current_pos	(0, 0)	(1, 1)	(2, 2)	(3, 3)	(4, 4)	(4, 4)	(4, 4)
distance	7.07	5.66	4.24	2.83	1.41	1.41	1.41
condition (dist <= radius)	False	False	False	False	True	True	True

Key Moments - 3 Insights

Why does the drone accept the waypoint when distance is less than or equal to the radius?

Because the acceptance radius defines how close the drone must be to consider the waypoint reached, as shown in step 5 where distance 1.41 <= radius 2 triggers acceptance.

What happens if the drone is exactly on the edge of the radius?

The condition dist <= radius is True, so the waypoint is accepted immediately, just like in step 5 where distance 1.41 is less than radius 2.

Why does the drone keep moving when distance is greater than the radius?

Because the drone must get closer to the waypoint before accepting it, as seen in steps 1 to 4 where distance is greater than radius and the drone moves closer.

Visual Quiz - 3 Questions

Look at the execution table, what is the drone's position at step 3?

A (3, 3)

B (2, 2)

C (1, 1)

D (4, 4)

💡 Hint

Check the 'current_pos' column at step 3 in the execution_table.

At which step does the condition dist <= radius become true?

A Step 4

B Step 3

C Step 5

D Step 6

💡 Hint

Look at the 'Condition (dist <= radius)' column in the execution_table.

If the radius was set to 1 instead of 2, at which step would the drone accept the waypoint?

A Step 6

B Step 5

C Step 4

D Step 3

💡 Hint

Compare distances in the execution_table with radius 1 to find when dist <= radius.

Concept Snapshot

Waypoint radius and acceptance:
- The drone moves towards a waypoint.
- It checks distance to waypoint each step.
- If distance <= radius, waypoint is accepted.
- Otherwise, drone moves closer and checks again.
- Radius defines how close is 'close enough'.

Full Transcript

This visual execution shows how a drone moves towards a waypoint and accepts it when within a set radius. Starting at position (0,0), the drone calculates distance to the waypoint at (5,5). It moves closer step by step, updating position and distance. When the distance becomes less than or equal to the radius (2 units), the drone accepts the waypoint and stops moving. The execution table tracks each step's position, distance, condition check, and action. Key moments clarify why the drone accepts the waypoint at the radius boundary and why it moves closer when outside the radius. The quiz questions test understanding of position updates, condition checks, and effects of changing the radius.