In 2019, we developed an automatic trajectory generation tool for cranes based on a mapping of its environment. All functions are performed on a Siemens PLC via the TIA portal platform.
The aim of this project is to save time on the routes taken by automatic cranes. In fact, these cranes usually return to their highest position before making a trip. Although this is safe, it is usually a waste of time.
The crane’s on-board robot knows the map of its environment, calculates the ideal optimised trajectory and can take the most suitable path.
The creation of the map required the installation of a sensor on the crane in order to take the measurements necessary for the creation of a complete map. The sensor selected was a safety scanner from Leuze. In addition to a number of safety features, these offer the possibility of retrieving measurements via UDP messages.
Profile by Sensor Studio (Leuze)
Profile retrieved by the automaton
The recovery of the measurements from the sensor and their assignment to the map takes into account a series of parameters in order to be directly adaptable to any type of configuration. When the map is created, the stock is scanned in order to carry out a complete mapping of the environment and thus allow the crane to start working. Subsequently, the map is updated dynamically as the crane moves to take into account any changes that are made.
Once the map is complete, all that is required is to communicate the desired start and end points to begin the calculation. The intermediate points as well as the speeds and accelerations to be set up in the three axes will then be communicated to the bridge. This calculation has also been adapted to be usable for overhead cranes that do not allow translations in the x-y plane to be performed simultaneously with the grapple elevation.
Finally, a supervision system combining the Siemens WinCC system and an independent application was created. The user can thus access a parameter setting page via WinCC but also visualise the map and the generated trajectories.
A test carried out at Technic One enabled us to confront the tool developed with real conditions. This proved to be quite conclusive, allowing us to validate the system we had set up. Below, the production hall is mapped in 2 passages of the bridge.
Picture of the hall
Mapping of the hall by the automaton