Is it me, or is the hexapod a little odd?

Hello,

When I open up the hexapod sim configuration, and run the below gcode, the results are not as expected. I try to rotate the B axis 90 degrees, but instead of rotating to 90, it gets up to 66 and then starts going backwards until it gets to 58. Whats even stranger is that after it gets to 66, all the other axes start moving around! Here's the gcode:

G0 B90
m2

I have only just started playing around with EMC2, and so this might be perfectly reasonable to an experienced operator, but i just can't get my head around it. Rotating the A axis 90 degrees works fine.

Could somebody please advise if there is something i'm doing wrong or if EMC2 hexapod kinematics are not yet fully developed?

Thanks,

Toby.

Well i'm not really familiar with the maths behind the kinematics, and so i'm not sure if a mathematical solution exists. Looking at the picture though it looks as though it should keep rotating until it hits a strut. And besides, it gets to 90 degrees when you rotate about the A axis.

Does anybody know where i might look for some technical info regarding how to determine if such a position is possible?

Thanks,

Toby.

P.s. is it expected that my x, y, z, a and c axes will move around if it can't get to 90 degrees? Or should it just stop when it gets to the limit?

I just tried to rotate the sim config and it jumps to home position when A increased beyond 45deg or smth. AFAIK it goes to singular configuration when A or B is large enough.

Anyway, the hexapod is _not meant_ to rotate more than 30-45 degrees.