The video said that you'd be able to pull cables along, but I'm struggling to see how you'd do that given that the actual walls of the "robot" are static once deployed. Is the idea that you somehow turn the cables inside out too?
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O=string============+ movement of growth ->
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O = spool of thread
When you see the vine on the other end, you can open the end to get the string, attach the cable to the former spool end, and start pulling the string to pull the cable. You want a light enough string for the vine to pull through, while being strong enough to pull a cable through.