This is my ATAT Emperial Walker model, made in Blender 2.79.
The scene starwars-ATAT.blend contain a fully rigged and textured (with Substance Painter) model. In the zip file you will find the fbx model for SP and the SP file, just in case you want to change some details on the textures.
Unfortunately, THERE IS NOT ANY OBJ OR FBX files about this scene, because of the rig made in Blender and this scene works only in Blender. So you can use the rigged model for animation ONLY IN BLENDER.
The scene at_at_model_DEF.blend contain the model without texture and rig. In the zip file you will find an obj or fbx with the model only. All the parts of the walker are separated.
I used this model for this compositing exercise: https://vimeo.com/289860294 So here you can see how it works.
Enjoy and may the force be with you!