Mission Definition

/in /by

Written by Elizabeth Nguyen (Project Manager)

Table of Contents

Objective:

The total time for each phase of the mission set is determined in order to ensure there is enough time allocated for the entire mission set to be completed in 120 min.

This document entails the breakdown of the mission set and how much time is split for each phase based on the maximum speed of each robot as provided in Mission Duration at Maximum Speed.

Phases:

  • Phase 1 – Record
  • Phase 2a – Individual Playback
  • Phase 2b – 4 Robots, 1 Maze
  • Phase 2c – Individual Playback (Pre-defined)*

* Phase 2c is optional and based on the success of Phase 2a

Robot Order: (from fastest to slowest)*

  • Pete-Bot** – 6 min.
  • ModWheels** – 7 min.
  • Sojourner** – 14 min.
  • Goliath – 18 min.

* All times have been rounded up
** Assumes no load

Speeds & Path Durations used:

Path durations were calculated and documented by Railan Oviedo. There are two documents where one addresses the path duration at maximum speed and another at minimum speed.

The bolded texts indicate which numbers I used to determine allocated time.

Types of Path Scenarios:

  • Shortest Path Scenario
  • Average Path Scenario

Speeds:

  • Half Speed – Min Speed
  • Half Speed – Max Speed
  • One-Third Speed – Min Speed
  • One-Third Speed – Max Speed

One-third speed was chosen (and suggested by Mark Huffman) to account for potential decrease in time due to added weight (since all but one robot have provided speeds under no load conditions). Although half-speed would be better to use for worst-case scenarios, it may not be as reasonable either. Also, average path durations were chosen to determine total time allocations at worst.

Breakdown of Mission Set:

  1. Phase 1 – Record
    1. Average Path Scenario at One-Third Speed (Max Speed)
      1. Total Time: 54 min.
        1. Path completion: 45 min.
        2. Rotation: 3 min. x 3 rotations = 9 min.
    2. Concluded Total Time: 60 min.
      1. Rounded up in the case that rotations are not 3 min. each or that some robots end up not performing up to speed due to added weight.
  2. Phase 2a – Individual Playback
    1. Concluded Total Time: 60 min.
      1. Considering that this phase is to test if the robot has properly recorded the maze, it can be assumed that the amount of time it takes to individually playback each robot is the same as Phase 1.
      2. Assuming that there is only one maze available, this means that the amount of time to complete the mission set has been allocated to both Phase 1 and Phase 2a.
    2. Alternative: (has been approved by Hill)
      1. If two mazes are available, then Phase 1 and Phase 2a can occur simultaneously.
      2. Once one robot completes Phase 1, it may proceed to Phase 2a on the second maze.
      3. This would allow Phase 1 || Phase 2a to be completed in 60 min.
  3. Phase 2b – 4 Robots, 1 Maze
    1. Concluded Total Time: 20 min.
      1. Total time is based on the time it takes for the slowest robot (Goliath) to playback its recorded path. At worst, that is 18 minutes; however, including factors such as robots potentially detecting each other and having to avoid each other, 2 minutes has been added in.
        1. Note: At this time, it is unknown how long it will take a robot to execute the Robot Avoidance Code and recover from its detour.
        2. If it takes even longer for a robot to avoid another, maybe a rule should be made where if a robot takes three attempts to correct itself and fails, then it fails Phase 2b and should be removed from the maze.
  4. Phase 2c – Individual Playback with Pre-Defined Maze
    1. This Phase only occurs if a robot fails to complete Phase 2a.
    2. Best Case: 0 min.
      1. All four robots must complete Phase 2a successfully.
    3. Worst Case: 60 min.
      1. All four robots fail to complete Phase 2a.
    4. Duration based on the number of robots at best and at worst in minutes:
      [Mission Set Table]
    5. Disassembly & Reassembly
      1. Total Time: 20 min.
        1. Based on Natalie Arevalo’s conclusion
          1. Disassembly: 10 min.
          2. Reassembly: 10 min.

Scenarios:

  1. Best Case Scenario – 100 min.
    1. Reasoning:
      1. Phase 2c is not required
      2. Phase 1 || Phase 2a (two mazes are required)
    2. Breakdown:
      1. Phase 1 || Phase 2a – 60 min.
      2. Phase 2b – 20 min.
      3. Phase 2c – 0 min. (if all robots succeed in Phase 2a or if Phase 2c is not included)
    3. Disassembly & Reassembly – 20 min.
    4. This scenario has been selected for the demonstration date on December 13, 2017.
  2. Worst Case Scenario – 160 min.
    1. Reasoning:
      1. Phase 2c is not required
      2. Phase 1 and Phase 2a occur separately
    2. Breakdown:
      1. Phase 1 – 60 min.
      2. Phase 2a – 60 min.
      3. Phase 2b – 20 min.
      4. Phase 2c – 0 min.
    3. Disassembly & Reassembly – 20 min.
  3. Absolute Worst Case Scenario – 220 min.
    1. Reasoning:
      1. Phase 2c occurs with all four robots
      2. Phase 1 and Phase 2a occur separately
    2. Breakdown:
      1. Phase 1 – 60 min.
      2. Phase 2a – 60 min.
      3. Phase 2b – 20 min.
      4. Phase 2c – 60 min.
  4. Disassembly & Reassembly – 20 min.