Change acceleration on the fly?

I hope this message finds you well. the issue with my machine's feedrate and acceleration settings while using the Python module's feedrate function. Despite initially lowering the feedrate, I am still encountering problems where the machine achieve speed of 1500mm/min on short segments during 2D movements. This has led to some safety concerns, as the spindle has accidentally hit me on the head due to these high speeds.

To resolve this, I am trying to implement a feature where, upon pressing a push button, the machine would operate at just 10% of its maximum speed and adjust the acceleration to 10% of the set maximum acceleration, to tackle the 2D sort segment speed up very slow, with a hop i do not hit me again.

Hello Rodw,

I tried offset concept with the current system, but at the end fallback to the same thing happening previously. 

I have added the hal files and opratated the system, when start eoffset and changing the accelaration the accelaration changes only on Z axis level offset movement only, but this did not affect the possible speed variation on the other axis, can be increase or decreased.

also modified (attached) the eoffset hal file and xml file to set the acceleration dynamically but the reasult the small files get buffered in the queue by emctaskplan calls and the velocity/accel change commands never get executed, also shared the log file..
 

Thank you Aciera for sharing tips, will definitely convert it to motion pins.

I have gone thrugh the motion section pins in  linuxcnc.org/docs/html/man/man9/motion.9.html , but i am unable to find the feed override inputs. can you please share more details on this...