Media stack height estimation in image forming apparatuses

An image forming apparatus comprising:

• a pick arm assembly having:
• a pick arm;
• and
• a pick roller mounted to one end of the pick arm to pick a media sheet from a media stack, wherein the pick arm is pivotally mounted at an opposite end to enable an angular position change of the pick arm relative to the media stack;
• and
• a controller operatively coupled to the pick arm assembly to:
• determine a range of motion of the pick arm during lifting of the pick arm from a media stack position to a hard stop position;
• estimate a height of the media stack based on the determined range of motion from the media stack position to the hard stop position;
• and
• indicate an amount of media sheets remaining in the media stack corresponding to the estimated height.

A non-transitory machine-readable storage medium encoded with instructions that, when executed by an image forming apparatus, cause the image forming apparatus to:

• adjust a position of a pick arm to zero, the pick arm having a pick roller at one end for picking a media sheet from a media stack and pivotally mounted at an opposite end to enable angular movement of the pick arm relative to the media stack;
• determine a range of motion of the pick arm during lifting of the pick arm from a media stack position to a hard stop position upon adjusting the position of the pick arm;
• estimate a height of the media stack based on the determined range of motion;
• and
• indicate an amount of media sheets remaining in the media stack corresponding to the estimated height.