[MOC] 6 Axis Robotic Arm, 4th revision

[Glaysche]

Here is version five of the robotic arm and remote control:

It is a bit more compact, lighter weight, and uses fewer parts than version 4.  Because of the lower weight and more specifically the lower moment of inertia of the moveable portion of the arm, I was able to use a faster gearing to get things to move faster.  Axis 2 and 3 are the two highest stress axes and those both move faster now.

By moving 2 motors out into the wrist, I no longer need to pass three functions through a turntable and no longer need the 3d printed part.  I now have only one axis going through the turntable.  The gear trains became significantly shorter and simpler.  You can compare with previous pictures I posted in this thread of the previous versions.

It's dense and compact but really simple now.  The LBG 16t gear in the middle is connected directly to the large linear motor that's in the elbow.  This drives axis 5.  The two small angular motors drive axis 6 and the gripper.  The only part I really don't like about this configuration is that there is no nice place to put the 2 port Spike Essential hub.  I attached it to the side of the wrist because that's the only place that doesn't interfere with the movement.  It looks a bit ugly there, though.

It's quite unfortunate that Lego is discontinuing the Spike Essential and Spike Prime education lines of products (and the Mindstorms line earlier) with no suitable substitute.  The hardware is really great.  Lego is not a software company and they failed so spectacularly on the software side that I think they decided to kill the whole concept of programable bricks.  PyBricks, while not perfect, is much more capable than any software Lego has ever produced.  PyBricks unleashed the potential of this hardware just in time for Lego to cancel it.

The parts needed to build this robotic arm are quite expensive so I don't expect many, if any other people build this.  I published it in the hopes that people will be inspired to build their own MOCs using some of these ideas.  It has been a lot of fun for me over the years.  Basically every time a new structural piece was released over the last few years, I would try to figure out if it would help me make a better robotic arm.  There were several parts that inspired almost complete redesigns.  That's super fun.  So I plan to put this project down until the next revolutionary part comes out or inspiration comes in some other form.

[AJB2K3]

Cool, I was wondering how to do the pass through and here you have already done it