Regression order planners demonstration made easy. Planning is essential for agents that act in an environment. To solve a goal intelligently, an agent needs to think about what it will do now and in the future. This applet demonstrates planning using the blockworld problem domain and STRIPS representation.

In the blockworld problem, a robot gripper must arrange a set of blocks into a particular configuration on the table. A block may be on the table, or placed on top of another block. The gripper can only hold one block at a time, and can only pick up blocks that have no other blocks on top of them. The problem is modeled by the following propositions:
* holding(B): the gripper is holding block B
* empty: the gripper is not holding a block
* on(B1,B2): block B1 is on top of block B2
* ontable(B): block B is on the table
* clear(B): block B has no blocks on top of it and is not being held by the gripper

Planning problems can be acquired by loading a sample problem or defining a new problem in "Create" mode. To load a sample problem, click "Load Sample Problem" from the "File" menu. Then select a problem from the drop-down list and click "Load."

To create a new planning problem, select "Create New Problem" from the "File" menu.

When creating a problem, the first step is to define the initial state. This is the starting positions of all the blocks in the problem. Be sure that you are in "Create Initial State" mode, as indicated by the button above the initial state panel at the bottom of the screen.

You can now create blocks by selecting "Create New Block" on the button panel and then clicking the position on the table where the new block is to appear. A block properties window will then open. You can click the "Ok" button to proceed or change the block's name and/or colour before clicking "Ok." Clicking again on the canvas will create another block.

Use the modes on the button panel to delete blocks and change the block's properties (name and colour). Note that blocks can be rearranged by dragging them to new positions on the table or onto other blocks. As blocks are created or rearranged, the Prolog-style text representation of the initial state is displayed and updated in the Initial State box below the table.

Requirements:
* Java

The license of this software is Freeware, you can free download and free use this calculator software.