Started Looking at Equations Again

Man, I am a glutton for punishment. I am starting to research equations for spiderbot leg articulation. Seems like I am dying to get back to geometry, trig, and algebraic equations. I don't really have to deal with calculus since the spiderbot will not be doing that much change that will require the calculations. I do need to define the overall requirements for what I want to do. In a nutshell, I want to take into account errors in construction and controlling (esp. things dealing with descrete commands), and also to define everything by a central point under the spiderbot. Alignment of parts will be an issue that needs to be dealt with in any of the equations. Hey, I haven't even gotten to the part about what the bot will look like have I?