0guyboom

[0guyboom]

New part innovation, while I’m still trying to find a solution to the main problem of keeping the legs straight I’m still making minor improvements to existing parts. I think this new version of the pins will be the final one.

The improvements I’ve made have come from looking at how the previous versions have failed. I noticed that the most successful one ended up cracking in a way that gave the pin arms more length to bend and so I’ve replicated that crack in the new design giving the pin better springiness without messing with the axel section. With the addition of a taller and pointier head these pins go in easily and are snug and strong once in place

[0guyboom]

Still working even though not making much progress, currently I’m working on things to increase precision in the parts themselves as I haven’t thought of any ways to improve the mechanics.

The main problem I’m having is that small deflections in the part where the leg attaches to the driver results in significant problems in the knee area. I have been able to improve this with precision but I think to make it work well I think I need to redesign something to hold the knee joint parallel

I’m continuing to make small improvements so hopefully I come up with something soon!

[0guyboom]

lets roll up with mama

[0guyboom]

This last modification has been the most difficult so far, mainly because I needed three layers rotating in different ways without interference, but I finally have a configuration i think would work well; though it still needs minor adjustments.

I have also used up the initial board I got for this project and I'm ordering much better material this time, though its going to take a week to arrive, I'd likely need it anyways as a still need to get the car attachment mechanism on each side as well as remaking everything to be ready for the cutter. I have a lot more work to do before this next step is out but i have time before school and work starts up again in a couple weeks so i think ill have this edition done soon!

[0guyboom]

Jaz

[0guyboom]

More laser cutting footage as an excuse for an update. The last design did not work out well, the interior wheel system while it worked for a single circle was just to much with 7, most of this design is nothing. However I think the 2 cam with a vertical bar system is still the best way to drive the leg so now I’m just trying again with a gear train. This might not be done for a while as it’s finals month and it’s likely I will become very busy and unable to work on this until summer. I’ll have a break before my job then so hopefully I’ll have this new version produced then!

[0guyboom]

Switching between these every day

[0guyboom]

Experimenting on yourself is so cool and sexy

[0guyboom]

Finding a way to attach the leg to the driving mechanism has been much harder than anticipated. I have been busy the last two weeks but have put many of the in between hours into figuring something out and I have come to this design as what I will prototype next

Working with this automata has helped me realize some of the things you have to do to get a mechanism that moves well especially when changing the axis of movement. The one I was trying to solve with this part of that you can’t have twisting driven by one action. What I mean by this is that the way the leg attaches to the driver has to remain vertical and for something moving in a circle to remain vertical it must also be spinning. Many of the designs I had for this I realized would just not work because it was an axel through the circle and the twisting was caused by the setup of the leg wanting to remain vertical but this caused twisting in the leg that caused the mechanism not to run smoothly, this can be fixed by the end of the leg having attachments on both sides but the circle end was more difficult

I tried a few thing but again ended up finding the best solution through math and geometry. I found that if I wanted a point that moved in a circle without rotating I could do that by having two equal circles connected by a bar at the same points. This will make the section of the mechanism much taller but with the height of the legs I have room and geometrically there is no other way to get the movement I want. I have enough time this weekend to print again so I can test this new design and see how it works out!

[0guyboom]

And here is the Video!! The legs are really working, even though there is some roughness that will easily improve through improving tolerances and the addition of another one of the round parts attached to the driver that I think will help with stability

One problem, I have realized the legs aren’t staggered and if they are not it won’t walk properly. One of the risk of limmeted simulations as I didn’t realize this problem as all my CAD models only had one leg. Well the fix for this shouldn’t be so bad and I already have an idea for it utilizing part of an older design. Hopefully with no more realizations to be made I’ll have a staggered and more stable version by the weekend, see y’all there!

[0guyboom]

Version 3.2

The new version 3.2 of the automaton, this version incorporates the new design for the legs as well as a new structure system with space for the attachment to the other parts. This version is very exciting as I'm getting to the point of going past getting the basic mechanics working and working on the entirety of the section and the ascetics.

Will be laser cutting tomorrow so will post again then when i get the assembly built.

[0guyboom]

Back again, after more experimenting had to be done to get the linkage right. I found I couldn't get it to move right and going back the the fundamental math I found it would never work in the configuration I had it, so it was time for a full mechanism revamp. luckily this time i found a tool to do it much better! this tool I'm showing is from the amazing Dave which you can check out here. I used his linage simulator to come up with a new design, the final version (left) you can see here.

I am already putting this into cad to prepare for printing so I know I will be ready soon, especially because the next weekend it the start of spring break! so i will have plenty of time and no other plans to get this new design into production!

[0guyboom]

It’s been a while, school and work has become very busy again but I have been working on this project in between. Unfortunately it has not been going the best

As seen in this video the wooden square axel pins have worked well, though some adjustments for spacing is needed. On the other hand it has the same problem as always with the leg twisting and catching on the main pivot shaft, and so I’ve done away with it. I now have a different design V4 that has a new joint making the horizontal movement and (from the simulations at least) it’s working great. The gait from this design is even better!

So as soon as I finish the new model and cuts I’ll post the new design and we’ll see how long until I can get a physical version working! Hopefully the last one, for the legs at least

[0guyboom]

Sorry i didn't end up posting anything for a while, i got incredibly busy with school. additionally, though I got the new method assembled and working i got a new idea while putting it together. instead of using a bunch of plastic pins this time I'm going to try to use square axels with inscribed circular holes, this this method i can laser cut every part but the bendy pieces which i hope will improve construction.

Luckily this week i have much less school work and no obligations to go to so tomorrow is cutting the new pieces and will again hopefully have something to show by the end of the week

[0guyboom]

V3 has had all its parts modeled and i will be cutting them tomorrow. by the end of the week we should have hopefully the last main version of the center piece working so we can move on to a minimum viable product, and from there, decoration and the head!

[0guyboom]

I’m back in school and also back to working on projects, I have lots of ideas I want to start of but what I’ve done in the first week is this, I got fabricated the new design for the driving mechanism and got it working!

This version needs some adjustment as the side walls have their dimensions all wrong so the parts don’t fit together right. This is mostly because I also changed how the structural struts are fitted. Now instead of using screws the plan is to have a tension fit. Then to get the spacing right I’ll have the laser cutter etch on to the ends of the struts, making them a bit thinner and able to fit into the holes

I’ve also got a whole new assembly model now, now made on the updated version of FreeCAD, it was fairly hard to make as FreeCAD doesn’t support assemblies by default, because I don’t need this one to move just putting the parts in the right spaces is enough

I’m a bit sick right now but I’m going to keep going this semester and hopefully get back up to speeds with making new things!