The Kansas City Space Pirates used a series of mirror arrays to redirect the sunlight onto the solar cells on the bottom of their climber. Each of these arrays had several (8?) mirror panels. These mirror panels were “focus-able” as they were mounted to the array panel by supports that could be adjusted in and out. They adjusted the support screws to bend the mirror slightly inward, allowing them to focus the mirror beam. I think the length of each mirror panel was about four feet. The mirror panels were made of glass and obviously couldn’t be bent too much or they would crack and/or shatter (a fairly common occurence I was told).
This video shows how they would “tune” the mirror arrays. They would reflect a light onto the side of a building – the pattern would show how focused their mirrors were.
This video was taken on the night of October 15th.