I’ve beefed up the case and the arms to be printed with the cheapest PLA available.
The lid has provisions for a fan.
I added the 3’rd servo for pitch control directly on the base, so no extra parts are needed to get to the OSR+ level. There are provisions to attach the pitch arm directly for people that want to use only 2 servos.
The geometry for the pitch is a bit different, but as from the user experience it works similarly to the OSR2+.
Also I added an under-user support, the user sits on the support, providing stability to the whole mechanism.
Planning to release 3D files on thingiverse as soon as I’m finished.
It can be screwed on a chair, but I was thinking like screwing it on a board or plywood and then the user can use it on bed, laying down, or on a computer chair. Basically the user weight provides the support.
Not sure if I’ll provide assembled units for sale, it depends on demand, I guess.
if the support has to be screwed to a board, it might be a good idea to make it so you can fold the support or else it will take up a lot of room. And i dont think a lot of people want to screw and unscrew it everytime they use it.
hey, interesting mod for the case. I don’t think that it’s the right way to increase the solidity of the arms.
With cheap servo, you need to make the receiver part as light as possible. Using extrusion width and adding walls inside the arms and on the perimeter would make the part stronger without increasing the weight if you are afraid that cheap pla isn’t strong enough.
I would suggest you to join Tempest patreon. There’s a lot of awesome mods on the discord for patron. Mines have been focused on reducing the weight to increase OSR2/SR6 performance.
The arms acts as I-beams, they need to be strong on up-down force, but flexible to support twisting. I just made them a bit wider, but without increasing the thickness to keep them flexible enough. They are working great.
The case supports all 3 servo’s inside, so it’s more compact, less things to print. Arguably is more aesthetically pleasing. Oh, the fan cools the pitch servo as well.
yeah, i was just saying that to make stronger arm than the default print you don’t need to actually increase the width, you can use some printing trick or add inner wall to make them stronger.
i doubt that even with cheap pla, using an extrusion width of 0.65 and 3 wall with low infill that the arms would be weak.
I’ve made a completely custom OSR2 (the OSR2x2) and i’ve actually decreased the arm width by a lot on it and it’s been doing fine for months.
I’ll be interested to see how well the new pitch servo location works. I’ve not pursued it myself because I’ve always liked the modularity of the current OSR2 design.
Oh, Wow! This is something! But your 4 arms is doing the same as 2 on the original OSR2, so of course the width can be smaller. I like your design, but you don’t have a pitch control and the roll is limited at best.
The difference will be most noticeable with pitch and stroke at the same time. I considered compensating for it in software by doing some kinematics calculations.
I’m finishing modelling a more compact version - I realized by inverting the main servo’s, about 20mm of space can be saved. As soon as I’m printing it and fixing potential problems, It’s good to be released.
With less volume comes more heat build-up. Have you ran any fast scripts for any length of time to check for any issues heat related? (A lengthy testing session is always on my planning list!)
I rally like the one-piece housing. This looks great!
