Our experience is that preliminary calculations are often missing elements that will have a major impact on cost. From a really long-term perspective it’s almost impossible to predict how production will change, and therefore the value of the investments.
That’s why we choose to focus on whether you should choose to have a robot for each machine or a robot that tends multiple machines.
One robot tending one machine
Cell with one robot per machine, giving the best possible versatility and availability.
The customer has six identical cells, making it easy to plan production and changeovers. The components are lightweight. A small robot with a payload of 10 kg / 22 lb is used, so the additional cost per machine is also small.
But the decision to use this particular solution with more robots was not based on cost. The automation part of production cost is actually very small. What makes this solution the obvious choice is its simplicity and versatility.
One robot tending three machines
Here, a robot tends three machines. This is a common solution for heavy components and long cycle times.
Heavy parts require a large robot, where a greater range is already included. Cycle times are long, giving the robot enough time to tend two more machines.
In addition, all the different varieties of parts could be picked up with one and the same gripper. For best availability, two loading and unloading conveyor belts are built in. The machine safety fences with doors at each machine implies that a halt in production or a maintenance issue for one machine doesn’t affect the other two machines.
Factors that play a role in the choice of one or two robots per machine
- Component weight
- Batch sizes
- If there are multiple processes inside the robotic cell
- If the machines to be tended are expensive
- Changes in production and the need for versatility
- The level of technical competence at the customer’s plant, as well as how advanced the solution should be