I almost got whacked on my head at a live event in rijswijk, cause I only had bungees on it. The flipper arm did do the full 180 degrees, and in doing so reached to about 1 metre behind the robot... swooshing thru a spot my where my head was half a second before.

In the series 7 gravity I had 8 strings of 10mm rope each capable of holding 2500 kg... the ropes started to bend a 30x30x3mm box section... So this type of rope will do fine.