Tuesday, July 31, 2007

The Hip Bone is connected to the Tread Bone

Well, this is my first version of my moveable hip design. It is based on the design that is on the B9 website by Mike Joyce. The plans on the site did not have a lot of detail needed for a machinist to take it and run, so I had to modify it. My machinist did an outstanding job. His name is James VanReenen and he is the owner of the North Dallas CNC machine shop. He does outstanding work and he is a fan as well (which really helps in doing this stuff).
Most of the drill hole sizes were not listed so he had to figure them out. In addition, the existing plans do not work with the current tread section offered by Eric Johnson so I made the following modifications: Foot mounting side supports that fit inside the tread section to hold the legs had to be made shorter and the holes for the wheels were in different locations. The leg stance width had to be made narrower, and the original plans had wood as the top and bottom plates for the hip. I changed those to aluminum to make it a bit stronger to withstand impact of a mobile robot for RC use.
With these modifications, Mike's design now works with Eric Johnsons tread section and Will Huff's rubber pants, legs and knees. For specific details and new drawings just send me an email and I will forward them to you.
One additional safety note, my tread section is all Steel. I have a soil sampler, motor drive units and batteries and power supplies in and just above the tread section so my CG is kept very low.
If you have aluminum tread sections I would seriously look at getting steel ones. If you want to stick with aluminum then I would rethink my design and probably use reinforced or extruded pvc and wood for the hip plates and legs. Remember, you want to keep the CG low and that means keeping the weight down the higher you go.

My Progress - First decisions and First runs

Fade in to Jerry sitting at his table reading RC and sci-fi magazines with his robot parts in the background....with the Lost in Space narrator voice overhead saying..." Last time as you recall, Jerry was remarking about what he had learned while acquiring parts and why he was doing this blog to help his fellow members out...little did he know that a discovery of a disease he would soon make would have dramatic consequences to his robot build........a disease that has plagued more robot builders than people killed by Cecil B. Demille (in his movies)......... It was the aluminum sickness :)

I was wondering how I wanted to proceed. Did I want to do it in wood, plastic/fiberglass, metal or a combination? I wanted my robot to be able to roll around on his own, talk, wave his arms like a blithering idiot whenever danger reared its ugly head and he had to be able to move around quickly. I had a similar decision I had to make with the R2 Builders group when I was deciding how I was going to build my R2D2 and my R5D4 and then it hit me. A robot just doesn’t seem like a robot unless he is made out of some kind of space age material like Titanium or some new endopolymer. Since both are out of my price range the next best thing is Aluminum. Also, my robot must have lots of motors, electronics and power! Arhh Arhh Arhh (the Tim Allen from Tool Time grunt). I can't wait to re-wire this baby!!!

Well I finally decided on a aluminum endoskeleton with a fiberglass, acrylic and rubber external covering. When I made my decision I saw a logo from the B9 builders site (I kid you not) it said....."To Out Build, Out Buy and Out do" as the club cry!!!!! I thought that was funny but I found out how true that statement was...I got the Aluminum bug!!!!! In the background Dr. Smith can be heard yelling in fear " Oh Noooo!!!!!" ...oh wait a minute...that was my wife yelling!!

Jump to the 3rd season theme with the countdown sequence with the Jupiter 2 flashing on the screen in the opening credits.....and then dollar signs flying all over with little wings Ok, well it may not be THAT dramatic but the aluminum bug has hit me hard. But I also wanted my robot to be fully mobile and to perform as if Bob May & Richard Tufeld were actually inside my Robot. So where do you start?

**Disclaimer** I do want to make 1 thing very clear here...you do NOT need to make your robot out of metal of any kind. It is just a preference. The end result is what you want him to look like and what you are happy with. This is what I have learned with the R2 and the B9 groups. You can look at 2 droids/robots side by side. Both are RC'd, both look real, both do exactly the same thing. The only difference is what they look like INSIDE (and the cost and the weight). You are the only person that will know this. So with that in mind, here are the chronicles of my build (along with all of my mistakes, lessons learned and improvements. Comments and observations are welcomed so this will benefit all that are reading this.

The first thing I did was to pick a starting point. That is usually a point where you are the most knowledgeable or can get the most parts for first. I started from the ground and moved my way up. I remember reading in the archives that the center of gravity was a concern especially in dealing with a tall robot. Tread Sections. Steel tread Sections. You need weight down low to keep the CG (center of gravity) low so it won't topple over easily. Also I needed a strong platform for a drive section, battery storage, power supplies and the soil sampler.

In addition, steel can withstand impact better than aluminum. Aluminum may be lighter than steel for strength (pound for pound) but Aluminum will crack and break easier than steel. It is also easier to make repairs to steel than aluminum. Anyway, here is a picture of my tread section. I got these from Eric Johnson and then modified them to accept a special motor mount for the motors that will power my robot (NPC custom Motors (12 or 24v Heavy Motors). I then modified them to work with my leg/hip actuator for the B9. The outstanding paint job was done by B9 club vendor Richie Schiavello (that is his B9 in the background with my Treads on each side).

Parts Aquisition & Learn while you Burn

Whoever said "Patience is a virtue" and "All things come to he who waits" never tried to make a B9 Robot!
OMG, when they said this was a builders club they never said I had to become a designer too! In the process of building my "Tin Plated Booby" I had to learn how to weld, use bondo, learn electronics and how to solder, paint, bend plastic without breaking it while retaining its new shape and how to essentially draw in a CAD program.
What a trip!! I should get a degree for this!! Hey wait....some places actually DO grant degrees for making Robots (MIT)!! LOL
However, dont get the wrong idea, I didnt create my Robot from total scratch. I did take advantage of the skills of fellow club members but no matter what I purchased, assembeled or designed from scratch, you had to learn about it to understand it and figure out what needed to be done or what to expect to make sure what you are getting is correct and of good quality.

There are a few sellers in the group who make parts available for club members but there is no builders council or standard among them to ensure that what you get from 1 seller will fit with another vendors parts. So most of the time you are having to make your own stuff, either from scratch or modifying someone else's work.
This is something you learn very fast when plunking down your hard earned money for parts that you have never really seen in person. Pictures can be deceiving. BE VERY CAREFUL and ask lots of questions. Follow up every phone call with your vendor to ensure no misunderstanding. There are a lot of excellent people on the builders list but all it takes is 1 misunderstood communication or 1 "bad apple" and it can ruin your total experience. That happened to me!
The enthusiasm about building your favorite robot can be over powering and lead you to make rash choices. Be cautious who you send your money to and to make firm agreements up front on delivery times if the part is not ready to be shipped. Don't assume anything!! Make sure you deal with people who are in the approved vendor list. I (along with others) got burned by a few builders who never delivered what was paid for. For some, they havent received their items in years. Those people have been banned yet there are some that still try to make a deal with them and they are paying for that mistake today! Dont be one of them!
Also remember when money changes hands it becomes a business transaction legally. A lot of people do not understand that; thinking that because it is hobby that the rules dont apply. They are wrong, they do. I have proven that time and time again.

On a lighter side, let me just say this for those who are new to this hobby. Remember that this IS a hobby, so do not expect a vendor to have something on the shelf just waiting for you to purchase it. Most of these items are made when the demand is created or requested. Enjoy yourself. Take your time on him. Do your research! Have parties discussing him with like minded friends. In this process you will have to learn a lot of things that you may not have ever had any experience with. It is a great way to bring the family together for a common goal and for all to share in. I mean Really, how many people can actually say they made a full sized, animated (and possibly) fully mobile robot??!!! He is great at parties, conventions and especially around Holloween!!
Oh, 1 more thing, its OK to also make other things from the Lost in Space genre. I plan on making the evil blue female robot and some of the hand lasers once I finsh my B9! I have already drawn her up and have the big bubble she calls "a head" in my garage....

Why am I doing this?

Back in the 1960's I watched a lot of science fiction. It intriqued me. It fascinated me. How did they do that? Why did they do that? How can I do that?!
The wonderment of a child's eye is the birthplace of endless possibilities.
Remember. We humans have [with but a few exceptions] (relatively speaking) have taken the Science Fiction of yesterday and made it Science Fact today. Isn't that wonderful? This showed me that anything is possible.

Science Fiction was a lot of things for me. As a child it opened up my imagination to what might be. How to approach something new. It was instructional; a door way to looking out of the box. This was a technique that has served me well. And in tribute to that gift I am making my favorite robots now. Kind of like a lasting rememberence to my youth and what might be if we work hard enough after it.

All you have to do is try and never give up if it is something you want to do! My father taught me that. I do so terribly miss him.

Do not ever give up and you can make it so! And so it begins.....