How do you reach the top of palletising?

Imagine you are planning a long hike in the mountains. In order to reach the top in the best possible way, in the optimum time and without any problems, you should make sure that you

·    use reliable equipment,

·   have accurate maps and

·    plan your route and day well.

After all, they don't want to be wandering through the mountains in the middle of the night or have to give up with broken shoes. The more shortcomings and mistakes you avoid, the better you will reach your destination.

What does this have to do with palletising? Well, even when palletising, you should pay attention to your "error budget" for the optimal solution. Even minor deviations from the target can have a major impact on palletising and make it unnecessarily difficult or even impossible to reach the peak.

So let's take a closer look at the individual points in relation to palletising:

The equipment - or rather the hardware - is first of all about the best possible stability. The more stable the system, the more precise and thus faster palletising can be.

Despite all the stability, you still want to be as "lean" as possible. Unnecessary things only hinder. If, for example, the base on which the robot stands is too wide, a robot or cobot with a longer reach may be needed - after all, the pallets are further away from the robot's base.

And of course, the equipment should last as long as possible, even if the going gets rough.

If we now place a small robot on a conventional lifting column, we can reach any desired height with European standard sizes, but we lose a lot in terms of precision, speed and acceleration of the robot. This is due to the fact that the instability increases with each further extended profile in the entire system. This results in a strong bending of the lifting column when the robot is moving at high speed. This can mean a displacement, of the pre-calibrated position, of up to 1 cm. So if a robot has an accuracy of 0.1 mm, this deteriorates 100-fold in the extreme position of the lifting column. This means that a large buffer of time is needed to compensate for the oscillations of the column. Normally, however, one does not have such a buffer available.

In contrast, our linrob linear systems are designed for high speeds, accelerations and weights, with extreme rigidity. This allows the robot to work at full acceleration even at great heights. Another advantage is that the axes are hardly wider than the robot base itself, which allows us to build a system with the smallest footprint and maximum accessibility for the robot. And of course linear robots from linrob are designed for a payload of several hundred kilos, so that we can handle the relatively low weights for palletising without batting an eyelid.

The more accurately the map matches the actual conditions, the better you can plan. It is also important to know where possible obstacles can occur.

In palletising in particular: can I get past the obstacle, where is the pallet actually located and how much offset does my gripper generate. Smaller deviations mean more efficient palletising already in the planning stage.

At linrob, we provide a digital twin for each of our systems and build all systems with the best possible precision. Supplemented by stable materials and generously designed accessories, we enable our palletising software from Native Robotics to plan the palletising process perfectly. Possible collisions are thus already detected and avoided during the simulation in the software. Likewise, it is possible to test and simulate in advance which robot is optimally suited for the task.

After the equipment fits and the conditions are at their best, it is now time for the concrete implementation. The planned route must be covered as quickly as possible, without causing collisions and, if possible, at the optimum speed. If you could now take a shortcut, the planning would be perfect. And just as with a good route planner, it is also important for good palletising software to take these points into account.

The operator specifies the sizes for pallets and packages and how many layers must be palletised. Is there an intermediate layer or not, may the packages be stacked directly on top of each other or with an offset? And that's it. The software takes care of the rest fully automatically, assembles the pallet virtually and checks for possible collisions in the process. But the order in which the individual packages are stacked can also have a great influence on the possible speed. But what about the shortcut? Here, too, the combination of our linear robots with the Native Robotics software helps. This software enables synchronous and coordinated movement of the linear axis with the robot. So that a much more direct path planning can be carried out. Depending on the size and complexity of the palletising task, up to 20% more speed can be achieved here compared to other systems, and that when using exactly the same robot.