I want to share about mecha leg concept which I think this might becoming helpful for us if we are seeking for an idea to scratch build the mechanism and the design of the leg. There are various types of mechanism here which I believed at least a pair of piston is required for the flexibility of the leg. As for my upcoming project, I need to prepare the very easy mechanism which require me to less scratch build the parts since im going to produce 12 of it. My upcoming project will be MG Twin Cater-Ball Train. This photo references will help to imagine and structuring the upcoming outcome for the build.