Hi
Your question is really complex. To what you’ve wrote, I think you should start thinking of building actual robots. I mean, you need to learn practical mechanical engineering. I’ve started building robots 1,5 years ago, the first attempt was connected with Mini-Sumo astronomical fighting robots. It is simply sumo for robots weighting maximum 500g, on a round 81 cm arena. It is simple enough not to get confused. The arena is black, its border is white, the enemy is the only object that is allowed to be taller then the floor. You need to check the ground color to find out where you are (if you need to run from an edge), and use some basic distance-measuring sensors to find your enemy. It is complex enough to learn much and have fun, watching your little mechanical animal fighting. I strongly encourage you to get involved in such a simple project. You will not learn that… specific common-sense that tells you how to join all those devices that a robot must contain in the most efficient way from any book out there. It is better to start off a simple project, and choose books and tutorials in order to beat the problems you face, than to learn only theoretical stuff.
Your CNC experience will be really useful, you will be able to design many parts from a scratch. The tools you’re about to buy are just perfect for precision robotics, like astronomical sumo, mini-sumo and fallow the line. I think it is best to get involved in a competition. On any contest I’ve been to so far, I’ve met lots of people that have passion for what they do, and who you can learn from.
Try to think of all the parts you want to have in your machine, then, think how to put them next to each other. Think of an efficient, light-weight frame (always, the frame is your enemy, as it does nothing!). Remember that you need to have room for wiring. Sketch all your ideas, and never get driven away from something crazy. If you hear “it will never work, this task is not done in that way” it only means, that the speaker has worse imagination than you
Ah, and just to let you know – my first robot was a total disaster, even it took 5-people team 3 months to build. We thrashed it
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The next one, hoverer, got us to the third place in our country, beating 63 other teams.