CoreXYish IDEX

While thinking of alternative ways to do the kinematics of an IDEX machine I came up with this hybrid kinematics.

The belt routing is like a CoreXY, but each loop is connected to a separate head. The Y axis (the gantry) is run directly by two belt loops, either by two steppers or pulleys connected with an axle.

The main goal is, compared to a pure cartesian, move the heavy X motors to a static position.

As the CoreXY loops holds the gantry perpendicular to Y it might be possible, or even better, to use just one Y belt. The system is over constrained as drawn.

Has anyone built something similar or seen this before?

I think that's almost equivalent to dual MarkForged kinematics, but it has the disadvantage that the A and B belt tensions will tend to twist the X axis.

CoreXY IDEX has been implemented using CoreXYUV kinematics, CoreXYU kinematics, CoreXY+MarkForged kinematics, and dual MarkForged kinematics (and possibly others that I am not aware of). RepRapFirmware supports all of them.

Edited 3 time(s). Last edit at 07/10/2020 01:59PM by dc42.

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Large delta printer [miscsolutions.wordpress.com], E3D tool changer, Robotdigg SCARA printer, Crane Quad and Ormerod

Disclosure: I design Duet electronics and work on RepRapFirmware, [duet3d.com].

It is indeed very similar to a dual MarkForge, just a slightly different belt routing. The kinematics math is the same.

I think you are right that the racking forces are strong and this idea is bad

I'm looking to go IDEX as well with my CoreXY but use the belt routing from a Dual Wire Gantry to control the second X Axis, which can move independent of the coreXY gantry due to the belt routing pattern, I have experience with dual wire gantry as my printer started out as a dual wire gantry and eventually went to CoreXY, but in saying this, with the second X gantry running independent of the coreXY system, you would still need to send Y commands to the main gantry while the second X axis/gantry runs independent is marlin capable of this type of kinematics?