Do the hybrid ones have any clever way to re-connect?
All the busses I've seen have this system where the driver has to walk to the back and pull on some rubber bands to put the tentacles back on the wires. If this could be automated, then perhaps you could omit wires at big junctions where it's most messy, needs lots of points, etc. Building & maintaining wires with 90% coverage might cost half as much as 100% coverage, I would guess.
If you search YouTube for “trolleybus automatic” there are a couple of videos. Looks like there are special locations where the catenary has a little plastic guide on it. It also looks quite slow.
Yes, where the hybrid buses connect to the wires (usually at certain bus stops), the wires have sort of "tentacle catchers" on them, shaped as upside-down Vs.
The driver just has to stop on the usual spot, press a button, and while passengers are boarding and exiting, the "tentacles" unfurl, and are guided by these "catchers" towards wires. The driver just watches for a light to go on on his dashboard.
It works pretty well - in many years, I have only seen once that the tentacles did not end up where they should, and the driver had to get out and manually correct it.
Seattle has this before for their downtown bus tunnel. Always annoying when the unfurling went wrong, but it was very workable. They got rid of it when light rail went in, and now run clean low emission buses in the tunnel instead (hybrid, natural gas) to avoid ventilation issues.
Just if anyone is curious, the technical term for the "tentacles" is pantograph. And if anyone is more curious about why it has "graph" in it, it's because the term refers to the old utensil for copying drawings which is similar in terms of aspect and principle.
Pantographs are only the bar mounted on a scissor-like mechanism that you find on light rail. They only allow for one electrical connection so they don't work for trolley buses.
All the busses I've seen have this system where the driver has to walk to the back and pull on some rubber bands to put the tentacles back on the wires. If this could be automated, then perhaps you could omit wires at big junctions where it's most messy, needs lots of points, etc. Building & maintaining wires with 90% coverage might cost half as much as 100% coverage, I would guess.
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