①Decomposition into subtasks

Here, the task that needs to be supported was decomposed into subtasks using the following steps:
Step 1. Checking the task
Check the initial and final state of the task.
Step 2. Decomposing the task into subtasks
The task procedure checked above was decomposed into subtasks according to the following types of subtasks. For each of the subtasks obtained, investigate the associated object (target object).

The images of the 6 subtask-types.
Subtasks List
Subtask types | Description | Example |
(S1) Selection |
Work related to selection of “target object” or selecting and picking up the selected object This is the subtask for selecting, in advance, the target object to be handled in the following five subtasks and the installation locations. Accordingly, it is generally positioned ahead of all the following five subtasks. |
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(S2) Installation (with explanation) |
Work related to the placement of the “target object” at the “installation location,” where descriptions are needed for the associated operations such as “push” and “twist.” | ![]() |
(S3) Installation(without explanation) |
Work involved in simply placing the “target object” at the “installation location” (“installation location” refers to the location of placement) | ![]() |
(S4) Deformation |
Work related to changing the shape of the “target object” | ![]() |
(S5) Size Adjustment |
Work related to investigating and setting the state of the “target object” | ![]() |
(S6) Observation |
Work related to the measurement of the “target object,” or user (point of gaze) movement associated with such operation. | ![]() |
Here, all the tasks are decomposed into subtasks but can also be re-summarized (re-grouped) during the display if a group of consecutive subtasks need to be presented individually to the user (for details, please check subtasks to be displayed).
Example: The task of placing the blocks on the foundation uses the following processes (4)
In this case, the task can be decomposed into the following eight subtasks by classifying them using the subtask types.
Subtask Number | Image | Subtask content | Subtask Type |
---|---|---|---|
1 | Pick up the blue block (2 × 4). | (S1) Selection | |
2 | Place the blue block (2 × 4) on the foundation (plate) five spaces (stud spacing) from the left edge and three spaces (stud spacing) from the lower edge of the foundation. | (S2) Installation (with explanation) | |
3 | Pick up the blue block (2 × 2). | (S1) Selection | |
4 | Place the blue block (2 × 2) on the foundation four spaces (stud spacing) from the left edge and two spaces (stud spacing) from the upper edge of the blue block (2 × 4) that has already been placed. | (S2) Installation (with explanation) | |
5 | Pick up the yellow block (2 × 4). | (S1) Selection | |
6 | Place the yellow block (2 × 4) on the foundation four spaces (stud spacing) from the right edge, and two spaces (stud spacing) from the lower edge of the already-placed blue block (2 × 4). | (S2) Installation (with explanation) | |
7 | Pick up the red block (2 × 4) | (S1) Selection | |
8 | Place the red block (2 × 4) on the already-placed blue (2 × 2) and yellow block (2 × 4). | (S2) Installation (without explanation) |
Once the decomposition into subtasks is completed, proceed to the next stage of the “Decision tracking DOF.”