Monday, March 3, 2008

B9 Build Off May 16, 17 and 18th 2008

The weekend of May 16th I am hosting a B9 build off at my home in Rowlett, TX. I hope to get a decent amount of participation from the B9 builders club with local involvement from the Dallas R2 builders and the Dallas Robotics group for those interested in the B9 as well.
Here we will be building, assembling and painting B9 robots. I have a machinist reserved for the weekend exclusively for the build off as well as 2 painting houses. So if you come prepared you could walk away with a completed robot. What an opportunity!!!! Bring out those B9's from the garage and get them functional!!
We will also be filming interviews of fellow builders with their stories as well as instructional "how to" videos on topics like basic construction techniques and materials, electronics, prep and paint, weathering, puppeteering, safety and other topics as requested. We have a lot of big names in the B9 and R2 word scheduled to attend. So please mark your calendars and come on by. Go to the B9 builders website on yahoo at http://www.b9robotbuildersclub.com/ for further details, agenda and location. I also included an area map for those needing hotel rooms. It is all FREE. Saturday evening will be a dinner (Texas Style of course) so I will need you to RSVP for that,
Here are but a few of the tentative speakers/guests: Mike Joyce, Tom Jozwiak, Charlie Garcia, Craig Reinbrecht, Phillip Hamilton, Bob Griener, Ken Pringle, Wayne Orr and Guy Vardaman from the R2D2 Builders group. The list keeps growing. So do yourself a favor and come on down! You won't want to miss this!!!!

Sunday, March 2, 2008

Machining Parts - What's it all about & Why is it so expensive?

I thought it would be a good idea to enlighten those uninitiated into all of what happens in the making of a machined part. I found it a fascinating and an illuminating process. Not realizing or appreciating what looked so simple, even automated, could generate so much work and such an expensive price tag. So many times we get sticker shock from what we thought was an easy or automated process and wonder what is going on. Are we being taken to the cleaners? It can certainly feel that way at times but the reality is making "1 off" parts is a very expensive endeavor. You need to understand and accept this to be prepared if you are going to take my plans (or anyone else's) to your local machinist to do some work. So lets start off with an FAQ of sorts about getting parts machined and then we will work out a concrete example from this build so you will understand what I mean.
***Disclaimer***: I am not a machinist nor do I play one on TV (or work for one). The experiences described below are from my personal experiences/lessons learned from dealing with several machine shops both local and distant (out of state) to the DFW area. This discussion is designed to help you understand what you are getting into and is not to be considered the only or definitive authority on the subject. Your experiences/mileage may vary. Lets start off with what you will be faced with when dealing with most machine shops.
Machinist Expenses
Setup Fees - The cost of entering measurements or dimensions into machines, etc. There is usually a minimum charge that shops assess. For example, TAP Plastics charges a 250.00 minimum fee for anything cut on its CNC machine.
Material Fees - The cost of the material used in its raw state
Machine & Labor time - Time charge for machine operation & operator monitoring/adjustment
Sub Contractor fees - Using other shops for completion like anodizing or welding parts together.
Shipping & handling charges - self explanatory.
Taxes - self explanatory.
Machine Shop Expectations from the Customer
Clear, complete communication. He will only do what you tell him to do. He doesn't read minds!
When you come into a machine shop you should know "what" and "how many" of a given item you want made. You also should know what you want it made out of like aluminum, plastic, steel, brass, etc). Not having or knowing this information puts the machinist in a consultant capacity. His time is Money. Don't think for a minute that he wont charge you to discuss how to do something if you do not already know what needs to be done. A good machinist SHOULD discuss what you are wanting done but don't go in there with the expectation that he is going to figure this stuff out for you for free and then only bill time and materials to make it. This is why a lot of machine shops will not deal with hobbyist for "1 off" projects or why requests of this nature are routinely done when there is no other work available.
You need to have clear, accurate drawings with exact measurements clearly identified. They do not have to be CAD drawings but those are the best to eliminate confusion and mistakes.
It usually does not matter if you have CAD drawings in a computer file or not. Good machinists can take a pdf or print outs of some type and work with that as well. However, no matter what you have as a reference, there will be a degree of human involvement required to get that information from the source into his machines and this is where the setup fee is based. In some cases the setup fee can be more than the cost of the material and labor combined to produce your part. The "key" to keeping your costs down is by dealing with a machinist that has already done the setup for this part if at all possible.
What is a "1 off" part or project? Quiet simply it is the making or the machining of any part or assembly where there is only a quantity of 1 involved. For example, A left and right hand version of something is still considered 1 item. There could be 40 different components to be made in the assembly of 1 item. That is still considered 1 item. This is the most expensive cost per item there is. Often, if you inquire, you could get multiples of that item you are making for only a fraction of what you had to pay for just 1. This is the basis for doing "runs" of parts so that others can benefit from the lower cost and availability.
Also, some shops will require you to put down 50% of the expected charge before they will begin to schedule or perform any work.
Customer expectations from a Machine shop
Clear, complete communication - Don't assume anything! Ask a lot of questions!!
Clear explanation of rates/fees - Make sure you ask for a detailed billing/charge list of services.
Authorization before action - No Shop should just go blindly ahead unless you authorize them.
Detailed billing - A complete, clear and accurate listing of item, cost, time and quantity.
Approval before payment - You need to make sure you are happy with it before payment. The
shop should work with you if there are any issues with quality or quantity of work performed.
Delivery Promises - Discuss at the very beginning any time lines you need to hold the shop to and make an agreement with them what will be done if they fail to meet that promise (like a discounted rate). Get it in writing. Shops have been known to do what is in their own best interests but if what you are contracting them for is time based they need to know that up front and that what they have or have not done maybe at risk if not delivered as promised. Recognize that some shops will not do business with an individual this way. That may be your clue to take your business elsewhere. You need to be reasonable when negotiating on this point.
A Practical Example:
Lets take the original aluminum waist plate I made for my B9. It started out as a block of solid 25 lb sheet of aluminum. The outside configuration/drawing was a copy of the PVC version of the waist plate that Andy Schwartz currently sells. The plate of raw aluminum currently runs at approx 4.20 per pound for 6061. It took (with a CAD drawing as a reference) 1hr to input those figures into the CNC machine. Most shops charge between 60-75/hr to do that. While the CNC machine is cutting the aluminum the CNC operator must monitor the process to watch out for broken bits, misalignment or other errors. Then he has to take that device out and flip it around and restart the process all over again to complete the project. That cost me 225 for time and 125 for materials equaling $400.00 dollars.
Now take that 1 step further and lighten that same waist plate. Instead of having dozens of data points to enter into the CNC machine, you now have hundreds of data points to enter into the system. All having to do with length, height, width and depth. The additional programming to do the diet version required 3 additional hrs of programming. To do all of this 1 time would of cost you $825.00 for 1 waist plate.
As you can see, the amount of time expended for that 1 waist plate makes it very costly. Now if you made more than just 1 of those waist plates the setup would only need to be done once. The other copies would only incur material and time charges, in this case it drove subsequent diet waist plates prices all the way down to 425.00 each; which is the price you would pay now.
I hope this makes sense to you and allows you to further appreciate what I have done for the club (for these parts) and the beauty of mass production.

B9 Electronics: The Inside Story Part 6 - the Finger Lights, Brain & Crown Animation

As I was using the light controller from Tom for the belly and chest lights, so to am I using another board from Tom for the finger and brain lights. It's basically the same board as the chest and belly lights controller card used in the Torso. The reason I used another one was so that I could get a different blinking and pattern rate than the torso. I wanted an asynchronous blinking pattern between the 2 sections. To me this gives a more realistic appearance of a real, functioning robot. Just as a side note, you could hook up everything to 1 controller card but I wanted that certain, special, something that only 2 cards can provide.
The crown and finger light movement is handled by the Hankscraft 12v 7rpm motor. You can obtain this motor from a number of sources and is readily available. The average price for this motor is 25.00. What I had a problem with was the wires coming out of the brain and finger lights passing through the brain cup into the neck. As you can see from the picture on the left from the B9 website, there isn't much room and I had to remove the wire sheaths and drill out additional wire routes to go around the Hankscraft motor. It is a VERY tight fit. Take care not to kink the thin wires coming out of the finger lights.

Saturday, March 1, 2008

B9 Electronics: The Inside Story Part 5 - Radar Section

My radar section uses the B9 creations' 2.5v regulated power supply and the Namiki Ear Motors for the ear sensors. Both of which were obtained from Eric Johnson from the club website. The Namiki motors are very sensitive to voltage and you can burn them out easily. The radar is moved by a digital robotic high power JR servo (JR DS8711). The range of movement is 180 degrees. 90 to the left and 90 to the right. I can fit a 360 degree servo in there or I could use a sailing wench servo for continuous rotation but most shots from the series do not show the radar moving greater than 90 degrees because the rotation of the radar section was controlled by Bob Mays head movement, so I decided to stick with that. I would suggest that you use a geared motor to rotate the radar section if you want to have 360 degree movement. However, in order to do that you would need to have a motor controller to be able to direct the degree and direction of rotation. That just means more money and more stuff to cram into the collar/radar area.
I also experimented with IR (infrared) sensors in the collar to direct movement of the radar when the robot is in animatronic mode to further simulate AI (artificial intelligence). The device I used was from Jim Shima's website called Hyperdyne and Hotcranium.com. These are the same controller cards that the R2D2 group uses for automatic dome rotation in relation to sound and IR movement detection. It works most of the time so long as you are not in a very loud or hot room. That is not always possible at a convention. Also, since the detectors are in the collar you have to be at least 48" tall for it to detect you. So what I decided to do was put in a IR detector in the rear vent bay to detect those pesky little carbon based replacements we call children. When it detects someone close it triggers a voice message saying to please stand clear and to step away from the rear vent and power pack.

B9 Electronics: The Inside Story Part 4 - The Torso

There is a lot of stuff that goes in the torso so lets start with the most basic question. Where is the power coming from and how will you split up or handle different voltage requirements for all of the electronic gadgets inside the torso? The answer is this: A 12v 12ah gel cell battery in the torso & a few 12v distribution boards. Now before we go any further let me say that I thought of using a slip ring to bring power from the tread section to the torso but I had to rule it out because of the way I am doing the hip rotation. The drive is off center and has an over sized gear cog which obscures the center of the CSS. I did look at the figure 8 procedure to accommodate such situations but However I still want to be able to do a 360 rotation. This defeats the reason for a slip ring. I also though of running wires up from the base and then have enough slack to be able to handle several 360 degree rotations but I just didn't feel the need for that. Most of the time I will not be doing a 360 degree rotation of the torso.
The distribution boards were originally created for the R2D2 builders group by Dan Stuettgen. I convinced Dan to change his board to include a few 3.3v connections for both rows of teeth lights making them more suitable for our club. Those boards should be showing up very soon. The additional change will also help the R2 group for those wanting the USB powered devices so this change helps everybody out (don't you just love inter-club cooperation)!!
The Torso Lights
Lets start with the belly lights. I have the lighting kit by Tom Wisnionski for the belly and chest lights. This kit is not for the faint at heart! There is something to be said for just doing basic wiring of the lights with flashing bulbs (but I have never been known for doing what's easy! ) This kit allows you to vary the blinking pattern and speed of the lights. This kit uses 6v bulbs. I put 6 volt bulbs in the brain, chest, finger and belly lights. It requires a degree of intense wiring but the instructions are (for the most part) clear and easy to follow.
The Dial Lights (chest lights) and the programing bay light hook up to Tom's board as well.
The teeth lights use the NKK lighted switches part number 633-215kkw016b1jb-r0 at Mouser.com. Those are the ones used in the replica robots. The lighted portion of the switch requires a 3.5v power source so be careful you DO NOT go above that. If the LED blows in this switch you need to get another switch because the LED's can not be replaced; and at 22.95 each that can get very expensive, very quickly.
The Neon
The neon that I use is the 16 row neon that was sold by Craig Reinbrecht. Craig only sells the 12 row neon now. Another vendor (Dennis Wilbur) sells a 12 row neon as well. Mine is connected to a Tech 22 model 8000 neon power supply (which needs 12v to operate correctly). While we are on the subject, let me show you the correct way to connect the 2 neon halves.If you look on the B9 website Craig has a diagram on what to do but his example shows a 1 piece neon. As you can see the wiring of the neon is like 1 continuous loop for the 2 halves. However describing it just isn't enough. It helped me to actually see what it looked like. So here it is.
I also discovered that soldering the high voltage wires to the neon is not a very good idea because the heat from soldering can damage the neon. It is best if you just use wire nuts.
Also, when testing the unit if you get a strobing effect or a flash of light then it is most probably because the wire leads you are using are too long. Neon is very sensitive to voltage and resistance. I have found consistently that if use VERY short test leads you will get a successful test. But in any event you should test each section of the neon first to make sure it lights up well. Then when you connect the 2 together the length of the test wire leads will make a tremendous difference in a successful test or not. It would be best if you would use the special high voltage wiring because your 12v power source is generating 8,000 volts. If you see a "beading" of neon then you will need to use the supplied diodes to correct that. Make sure you only apply the diodes to the upper section of the neon. Please note that there is a solid black line that denotes the orientation or flow of electricity through out the neon. Please make sure you have the correct orientation of the diodes or the beading may still continue.
The Bubble Lifter
The bubble lifter uses a GWS777 6BB Robotic servo. This servo can lift over 20 lbs but only if the servo is externally powered with a 6v battery or some other power source. This amount of power is necessary to lift everything above the radar section and be able to move it up or down quickly. A fast bubble movement is imperative if you are to replicate the synchronous of bubble "attitude" when the robot when asking or saying certain phrases. The auxiliary power device that the GWS servo would plug into is shown in the picture to the right.
The Sound System
I decided to use the CF3 sound system by ACS Control Systems Inc. It is the sound system I use in my Astromechs. These typically run around 179.00 plus any additional IO input cards, sand cards and external power supplies if your robot uses AC power only. It is a beauty and easy to use. It can handle as many as 48 contacts (which is what mine has) that can trigger various sounds and contact closures remotely, automatically or in response to other contact closures, IR devices (active and passive), etc.. It has an interchangable SAN card that can hold any amount of sounds files wether they are WAV or MP3. It even has a scripting routine along with background files that can be played (the robot sound).
To trigger sounds without the need of a computer I included a couple of 12 channel RF remotes from Cold Fusion to activate those sounds while he is mobile. These can be found on eBay for as low as 24.95. This is a great little remote that has a teriffic range (500 feet unobstructed). So my robot could be way ahead of me and he could respond to the crowd and no one would see who is controlling him.
Arms and Claws
Now you may have noticed that I conspicuously left out the motorized arms and claws. This will be a surprise that you will only see at the build off. I will show you the customized controller board that I had made but that is it for now.... muhahahahahaha ..oh sorry...that was my Dr. Evil laugh coming out.... :)