# Obstacles and collisions

During robot movement, it may encounter a number of obstacles, either with fixed or variable height. Wepall provides special means to handle each type.

# Static cell elements

Fixed-height elements such as pallet or cardboard warehouses/dispensers, characterized by having a constant height over time. To avoid this type of obstacle, as a general rule the Overpick Offset value of the pick preset is used in a fixed manner.

# Previously placed products

During the placement movement of one or more products, there is a possibility of collision with other products previously placed on the pallet. For this reason, it is essential to take into account the approach direction. Additionally, depending on the type of gripper used, when placing a product it may open in directions that are not desired, pushing previously placed products. This issue must be addressed during the design phase by placing boxes in the correct order and angle.

Review the design considerations to learn more about this topic.

# Collision between zones

Each recipe, when defining its pick and pack presets, uses one of the 4 available mapping zones.

If your intention is to interleave multiple recipes depending on your production (each recipe uses a different mapping zone), you must consider that while the product is being transported by the robot, it may pass through other zones with previously placed products (recipes that are partially completed and waiting), and in that case a collision is more than likely.

To avoid these situations, the user can indicate which other zones the robot must take into account while working in one. In other words, the robot will "know" that it must maneuver and raise its arm when passing over those other zones, because it will certainly cross them on its trajectory from the pick point to the placement point.

The maneuver height is calculated using—at minimum—t