I have been given a project to design a bunk bed for a caravan. This must in some way be stored when not in use against the wall and fold out over the permanent lower bunk or could perhaps be integrated into the lower bunk as a sandwich design and could be moved up and fixed into position when in use. I was wondering if someone could throw some general ideas my way regarding the mechanisms i could use. I have sketched 2 rough ideas and i could scan then and send them via e-mail if someone could give me a bit of help with them. Or give me a link to some eng drawings of folding/sliding mechanisms etc. My first idea involves a bunk folding from a position fixed to the back wall and the legs could fold down and lock into place over a permanent lower bed, i need to be specific on the mechanisms to use now - advice would be much appreciated. Also my second idea involves a sandwich design where the user pulls the bed up on sliders fixed to the back wall and it locks into position.... Thankyou very much..