here is my first entry:
just about everything was made from cylinders except for the bottom section and the feet. the bottom section is such an odd shape so i decided to use springs so i didn't waste too much time trying to get it to look right. the feet are just simple boxes with smaller boxes to stand in for the tracks. the arms are cylinders with the bend modifer applied and then i extruded edges to mimic the look from my reference image. the main body is a cylinder that i extruded and beveled and the added the symmetry modifer.