In order to enable the telescope arm to extend outwards from both sides, some special design stratagems were necessary. The energy chain used play a key role in this. It has to satisfy the requirements regarding weight, travel speed and compactness and enable a high degree of dynamic responsiveness in order to ensure that the telescope arm extends outwards from both sides.
For SEMA, it was also important to create as much storage space in the system as possible and this is why the handling system had to be designed to be as compact as possible. Initially proposed possible solutions with individual chains for each telescopic axis were not feasible. Another more suitable solution therefore had to be found.
Due to the requirements in terms of weight, travel speed and compactness, an energy chain of the E4.38L series was the clear choice. Their lightweight makes the required dynamics possible. Due to the limited amount of installation space, two chains from this series were ultimately combined with each other and used in an S shape with very tight bend radii – a kind of very sharp S curve.
The energy chain guide must automatically return to the basic position after every loading cycle in order to avoid collision during the subsequent movements and so the two chains were mounted next to each other but rotated by 180 degrees in relation to each other in order to enable movement in both directions and, at the same time, make sure that the chain remained inherently stable.
Due to the installation situation, there was a further problem, namely that the small bend radius of the chain was too small for the cables used. The cables were therefore also obtained from igus – already harnessed as readycable. The chain and cables were used as a ready-to-install harnessed readychain system . The benefits for SEMA were the system guarantee and the time saving.