Box Depalletizing—One by One

Selected by default, i.e., send the current waypoint to the receiver, such as the robot. Once deselected, the current waypoint will not be sent. However, the waypoint will remain in the planned path.

Unselected by default. When non-move Steps, such as Visual Recognition, Set DO, Check DI, etc., are connected between move-type Steps, the sending of the waypoints will be interrupted, and the real robot will take a short pause, reducing the smoothness of running.

When this parameter is selected, the project will continue to run without waiting for the current move-type Step to complete execution, and therefore the robot can move in a smooth way without pauses. However, selecting this parameter may cause the execution of the Step to end prematurely.

Why will this feature cause the execution of the Step to end prematurely?

Mech-Viz will send multiple waypoints simultaneously to the robot when the project is running. When the currently returned JPs of the robot correspond to the last waypoint sent by Mech-Viz, Mech-Viz will assume that the robot has moved to the last waypoint.

For example, there are 10 move-type Steps in a path, and the pose of the 5th move-type Step is the same as that of the last move-type Step. When the robot moves at a low speed, the current JPs will be sent to Mech-Viz after the robot moves to the 5th waypoint. Since the poses of the 5th move-type Step and the last move-type Step are the same, Mech-Viz may mistakenly determine that the robot has reached all waypoints and prematurely ends the command.

Once Detect collisions on target objects is enabled in the Collisions panel, selecting this parameter will disable the collision detection between the robot, robot tool, and placed target objects. Typically, this parameter is selected in the move-type Step following the Step whose Pick or place is set to Place to avoid false collision detections.

Application Example:

The TCP of a depalletizing vacuum gripper is usually set inside the model rather than on the surface of the vacuum gripper. As a result, when picking a box, the vacuum gripper model may overlap with the box model. However, the software does not detect collisions between the end tool and the picked target object, so no collision alarm will be triggered during picking. Once the robot places the box down, the picked box model becomes a scene model, and the software will start to detect the collision between the end tool and the box’s scene model, triggering a collision alarm and preventing the completion of the palletizing task.

Once this parameter is selected, no collision between the robot, end tool, and the model of the placed target object will be detected, and the above issue will be resolved.

Usually, Auto can be selected, i.e., directly apply the Point cloud collision detection settings in the Collisions panel. For the Steps between picking and placing, Check collision can typically be selected.

This parameter is only visible when the Waypoint type of the move-type Step is set to Target object pose.

The target object symmetry here refers to the Rotational symmetry of held target object predefined in the target object editor during collision model setup.

Once this parameter is selected, a Plan failure exit port will be added to the Step.

If the path planning of the current Step succeeds, the workflow will continue along the Success exit port. If the path planning of the current Step fails, the workflow will proceed along the Plan failure exit port. If multiple move-type Steps with “Plan failure” exit ports display in the same plan history entry, the workflow will proceed along the “Plan failure” exit port of the first move-type Step.

Once this parameter is selected, collisions between the held target object and the scene model will not be detected, reducing the computational load of collision detection in the software, speeding up path planning, and optimizing the overall cycle time.

Once this parameter is selected, collisions between the held target object and the robot will not be detected, reducing the computational load of collision detection in the software, speeding up path planning, and optimizing the overall cycle time.

Once Point cloud collision detection is enabled in the Collisions panel, selecting this parameter will stop detecting collisions between the held target object and the point cloud, further reducing the software’s computational load, shortening path planning time, and enhancing the overall cycle time.

Typically, “Vision Move” will only use one pick point in the vision result. However, once this parameter is selected, the robot will move through all waypoints corresponding to the pick points in the vision result at one time.

This parameter is usually used when the robot moves in a fixed path where no DO signals will be sent, such as the gluing application.

When this feature is not enabled, each time “Vision Move” plans a robot picking path successfully, the rest unused pick points will be discarded. If this feature is enabled, the pick point that leads to a planning failure and the rest unused pick points will be retained and used for the next planning. This feature should be used with the “Whether Pick Points Are Used Up” Step.

When there are multiple pickable objects in one vision result and it can be guaranteed that picking one object will not affect the poses of other objects, this option can be enabled. Once enabled, the vision result will be reused until all pick points have been used, without the need to capture a new image.

Application Example

This feature enables multiple “Vision Move” Steps in which the same vision service is selected to share the vision result.

When one “Vision Move” Step plans successfully, the corresponding pick point will be used, and the unused pick point will be used by the next “Vision Move” Step with this feature enabled. After all “Vision Move” Steps that share the vision result complete planning, the rest pick points will be discarded.

In addition, this feature can be used in conjunction with the “Reuse Vision Result” feature. When “Reuse Vision Result” is selected, the rest pick points will not be discarded even after all “Vision Move” Steps have completed one round of planning.

Once the Update Bin Pose with Vision parameter is selected, the bin will be recognized and located simultaneously while the camera captures the image for target object recognition. Therefore, the bin pose in the simulation area can be updated dynamically, which facilitates the collision detection algorithm to effectively prevent the robot from colliding with the bin.

This feature will provide three fields, scene_object_names, scene_object_poses, and scene_object_sizes, in the vision result to define the name, pose, and dimensions of the scene object to be updated.

This parameter group is mainly used to avoid picking on the same pick point in scenarios where the object cannot be picked successfully.

Once the Filter Out Unlikely Pick Point parameter is selected, you can adjust the following parameters.

The software sequentially applies three strategies—Center to center, Edge midpoint to edge midpoint, and Corner to corner—to attempt the vacuum gripper offset.

The software adheres to user-defined offset priorities to attempt the vacuum gripper offset.

There are three custom strategies in total, which are Center to center, Edge midpoint to edge midpoint, and Corner to corner. You can specify the attempt sequence for each strategy by configuring the Offset Priority parameter group.

In the figure below, the orange rectangle represents the box, and the gray rectangle represents the vacuum gripper. The green part of the vacuum gripper indicates that the section is activated, while the red part indicates that the section is deactivated.

The software attempts the offset according to the user-specified Edge/corner ID sequence (e.g., 11, 21, 31, 41).

The edge/corner IDs are generated automatically in the vacuum gripper configurator. The two-digit numbers at the edge of each section are edge/corner IDs, as shown below.

You need to set a reference point to enable this feature. The offset strategies will be sorted according to the distance between the TCP and the reference point, and the offset strategy with a TCP closer to the reference point has a higher priority.

This parameter specifies the minimum proportion of a box’s upper surface covered by the vacuum gripper when the vacuum gripper attempts to pick a box. If the coverage is below the threshold, it is considered that the vacuum gripper cannot attach to the box firmly and the picking is not allowed.

In addition, when the upper surface of a single box is larger than the entire vacuum gripper, and all sections of the vacuum gripper are activated, the coverage can reach 100%.

Supposing that this parameter is set to 50%, the picking feasibilities are shown as below.

This parameter specifies the orientation of the vacuum gripper relative to the box group during picking.

In actual depalletizing process, when the sensors attached to the vacuum gripper near the edge of the box, the software may mistakenly detect that the box is dropped due to large gap between boxes, loose suction at the edge, or other reasons.

To prevent these issues, you can select this parameter and set Box Edge Removal Distance.

DI sensors that are within the removal range will not be taken into account in the box drop detection.

The width of the red frame shown in the figure below represents the Box Edge Removal Distance. For actual application, please adjust this parameter according to the on-site requirement.

Select Limit Total Count and you can set the maximum Planned Count and other parameters.