deb,
I found your posting a little confusing. Are you trying to design a semi-circular table (indoor or outdoor?) that could be sized to fit someone in a wheelchair? If that is your question then I would say that a good carpenter could easily build a sturdy one to hold the weight of potted plants. Sounds like a good idea. Why would you want the table to be hinged? That confuses me unless you plan to store it a part of the year.

HAVE YOU TRIED THE ACCESSIBLE GARDENING FORUM YET?? LOTS OF GOOD IDEAS... ALSO MEL BARTHOLOMEW IN HIS SQUARE FT GARDENING BK, HAS A SECTION ON ADAPTING HIS METHOD TO ELEVATED PLANTING BOXES FOR HANDICAPPED GARDENERS... EG, A LARGE 4' X 8' SHEET OF PLYWOOD LAID ON TWO SAWHORSES COULD PROVIDE A BASE FOR PLANT CONTAINERS...GOOD GARDENING TO YOU, DESPITE ALL THE OBSTACLES,K.