@ Tony, i actually have a 80% complete B9 in the computer, just waiting to get out at any scale! But have you seen the new Mobeus B9, its beautiful! And thanks so much for the offer on any info/advice/help. I'm going to need it! NEW B9 1/6th scale

@Dave, Thanks again at taking a look. Its shaping up nicely. Hopefully something fun to stick a Ezb v 4 into. Hope those ship REAL soon! Hint hint!

@will, if you do need any tech help on hardware or programming for your project, you can email me direct at toymaker(dot)tony@gmail(dot)com, as I have said I would be happy to help.

Wow, I like the Mobeus B9, I wish I was a better modelmaker, if I was I would get one but I am useless at assembling model kits!

@Will , Wow, your going to be able to print a B9 at any size? That's mind blowing! I imagine needed and unavailable parts could be printed the same way. A person could print out a power pac, neck bracket, finger lights or ear posts! Your new project is just screaming for a V4 EZB.

I have one of these new Mobeus B9 models now waiting to be put together. Sadly my big B9 comes first and I don't see myself having time for the little model for a long time.

I'm going to hijack this thread a little here (sorry Will) ; @Tony, could you take a look at my other Kangaroo thread? If you see any ideas on programming ramping my Kangaroo X2 and have a little time I could use a little advice in that thread. No worries if you don't have the time. OK, Hijack over.

@Will , speaking of ramping, is this a problem with the motors on your new project? Without giving too much away are your motors starting and stopping smooth enough for your distinct taste?

@Dave Everything is direct drive ( that is all the axis are connected directly to servos). I'm not using any exotic motors, so that the average person can get off the shelf components to assemble it. With servo speed, I can keep some parts from tearing apart by jerking around from the servo, by basically damping the speed. I am looking forward to 180 steps for the servos! Nice smooth movement. If the front becomes a little too heavy I will counter with springs on the opposite side , a great trick from my animatronic days.

Yes A b9 could be printed, they even have some very cool rubberly type filaments called ninja. This stuff is a close as you can get to rubber. Its actually a urethane and needs a special extruder. But exciting to print in all these cool materials. If you have a cool $330,000 laying around, you can get the new Objet. You can print in many types of materials at the same time. So you could print a pair of glasses one material for the frames and the clear lenses at the same time. Its getting really very cool. Here is a link : Objet Connex3

@Will, can I ask your advice, from your experience of animatronics and springs etc can you help me with a problem that I have with the EZ:1 arm which has backlash and flex issues in the arm assembly which can be seen in this video.

Do you think counter springs may work on this type of problem? I want to try to reduce the flexing etc.

Thanks in advance for any help.

Tony

@Tony, every time I see this video I'm amazed. We're so lucky you have a robotics person of your caliber a member of our group.

I don't even to pretend that I'm even close to an animation expert like Will but I do have a lot of building experience. Here's what I see (and I'm sure you do too); The length of your arms and their weight is causing it to bob at the joints whenever they move. I know of several ways to stop this. The surest way is to beef up the joints with heaver brackets and larger motors. Of course I know that's not an option because of your design and cost restraints. Perhaps at least a different type of shoulder joint should be considered. In a different thread one of our forum members uses a Vex Turntable bearing kit for a shoulder joint. It looks like a good answer to robot shoulder joints because it's small and strong. Look here:

Pics of Vex Turntables

Vex Turntables Web site

Other then that I think your only other choice to stabilize the arm joints are springs or small gas struts. Struts are intriguing and really do a nice job. I have a pair on my B9 to assist with the weight when he bends over at the hips. I was amazed how nice it works and when at rest they hold position and weight with no pressure on the motor shaft. The down side is you need it sized properly so the weight of the part your supporting or gravity will assist the motor. They also look cool (think of C3P0). Springs are your other answer but I have little experience here. I know they have been used forever with success to assist motors. The other Tony that built his Lexi 3000 used them in his arm design. They really worked nice for him and he even installed them in a small tube to help them work and keep them from view. I was really impressed with his solution and how it turned out with the springs being hidden in the tubes.

Good luck! Your work and talent is amazing!

@Tony, I'd say Dave is correct. The wobble comes from joints or motors that are not tight. Springs could take out alot of the wobble and dampen the motion. Think articulated desk lamp.

Hey Dave, I agree the Vex turntables are an awesome cheap but strong shoulder joint... You can even use 2 motors (that's what I have done) to double your lift load...