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.
The block required for the next work subtask was selected and picked up from several (available) parts.

(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.”
Install the power supply unit in the PC chassis using the “push at a certain angle” operation.

(S3)

Installation(without explanation)

Work involved in simply placing the “target object” at the “installation location” (“installation location” refers to the location of placement)
Place the block at the installation location.

(S4)

Deformation

Work related to changing the shape of the “target object”
Tie a rope.

(S5)

Size Adjustment

Work related to investigating and setting the state of the “target object”
The required length of the rope was measured using a ruler.

(S6)

Observation

Work related to the measurement of the “target object,” or user (point of gaze) movement associated with such operation.
Check the backside of a large part.

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 NumberImageSubtask contentSubtask Type
1Pick up the blue block (2 × 4).(S1) Selection
2Place 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)
3Pick up the blue block (2 × 2).(S1) Selection
4Place 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)
5Pick up the yellow block (2 × 4).(S1) Selection
6Place 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)
7Pick up the red block (2 × 4)(S1) Selection
8Place 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.”

Information Design Table
User Tracking DOF:
Subtask Number Subtask Content Subtask Type Object Tracking Information-presentation Method Operation
Add this row below(), Delete this row(), Replace below()