Planning operations to avoid collisions for simultaneous multi-robot work areas. (Potentially an in-depth walkthrough?) Manual methods of mitigating collisions for multi-robot simultaneous. Procedure on how to rearrange and change path directions to avoid multi-robot collisions.
A dome shaped part requires edge following operations on five contours.
These operations will be distributed between two separate robots and processed simultaneously.
In some cases, the default robot trajectories for the multiple robots may result in collisions between the robots.
Move start point
Operations 1 and 3 are processed by different robots, and there is a collision between the joints of the robots.
The proximity of the entry/exit points and timing of the operations causes a collision.
One way to solve this collision is to move the entry/exit point on one of the profiles further away.
In the Device tab, in the Operations pane, right-click an operation and select Edit in task.
Select the path, then click the red ball at the entry/exit point.
Click a point along the path to move the entry/exit to a different location.
In the Task tab, select Apply and then OK to keep your changes.
In the Device tab, select Calculate.
Confirm that the collision no longer occurs.
Change path direction
For applications where it is possible to change the direction in which a path is processed, you can try changing path direction to solve collisions.
In the Device tab, in the Operations pane, right-click an operation and select Edit in task.
Right-click the path (be sure to right-click one of the vectors on the path), then select Path > Invert direction.
Confirm that the path direction is reversed.
In the Task tab, select Apply and then OK to keep your changes.
In the Device tab, select Calculate.
Confirm that the collision no longer occurs.
Rearrange operations
Another method of solving collisions is to plan and rearrange operations. This can be done by changing the order in which operations are sequenced for a given robot and/or reassigning operations to different robots.
When planning the sequence of operations in a multi-robot cell, consider required spacing between robots, how much room is available in the work cell, whether you need to include an additional buffer distance for safety.
Change the sequence of operations for one of the robots:
Here Robot_1 is processing operations 1 and 2, and Robot_2 is processing operations 3, 4, and 5:
Operations 1 and 3 may be too close together to process simultaneously. Instead the sequence of Robot_2 could be changed so that operation 4 is processed first. This would leave more space between Robot_1 and Robot_2 as the operations are processed, lessening the chance of collision.
Use the control handle to drag the operation to a different place in the sequence.
Select Calculate to see if the collision is cleared.
As you rearrange operations, the robot trajectories will be updated. Pay attention to the changes in paths as the robots move between home positions, and between operations.
Notes:
Rearranging operations in the Device > Operations pane.
Change sequence of operations within a given robot
Move operations from one robot to another
Further reading
What about velocities, accelerations, and real-world deviation from programmed paths?
Use safety envelopes to give “buffer” for collisions, add them as intereference groups in the cell.
Do multiple robot cells communicate with one another? Are they equipped with sensors to detect adjacent robot position?
Spatial
If you plan a progam so that the robots never occupy the same space at any point in time, this is the safest with least chance of collision.
Temporal
If two robots must occupy the same space due to the required trajectories, timing the operations is critical for minimizing risk of collisions.
How much time to leave between operations' intersections in space? 1 second, 30 seconds?
What is the typical difference between ideal vs actual speed due to acceleration, payload, and whatever else might factor in?