How To X Pointer - MOARdV/MOARdVPlus GitHub Wiki

The X-Pointer instrument is used to provide lateral velocities or displacements. When configured for landing, the X-Pointer can be used to nullify sideways movement, ensuring a vertical landing. When used for rendezvous, the X-Pointer can be used to place a target directly in front of the vessel, and to cancel any sideways drift relative to the target.

(TODO: Updated illustration)

The instrument consists of the X-Pointer power switch, the mode selector switch, the scale selector switch, error flag indicator, and the X-Pointer instrument.

Power Switch

The Power switch (X-PTR) is used to enable the X-Pointer instrument.

Mode Selector Switch

The MODE selector switch controls which mode the X-Pointer is operating in.

• VEL: The X-Pointer is in docking velocity mode. It provides the lateral velocities of the craft relative to its target in meters/second (as adjusted by the scale selector).
• DIST: The X-Pointer is in docking distance mode. It provides the lateral displacement of the craft from its target in meters (as adjusted by the scale selector).
• GRND: The X-Pointer is in ground velocity. It provides the lateral and forward velocity of the craft in m/s (as adjusted by the scale selector).

When used with the ARRT (see How to ARRT), this instrument can be used to guide a craft to a stable landing (no lateral velocity), or to rendezvous with a target.

Scale Selector Switch

The SCALE selector switch changes the units being displayed by the X-Pointer. It can be switched to x1/10, x1, or x10. When the X-Pointer is active, the selected scale is displayed below the main window.

Error Flag Indicator

This indicator (X-PTR ERR) is enabled when the X-Pointer is configured for target for docking while there are no valid targets being tracked.

X-Pointer Instrument

The instrument itself consists of legends on the left and bottom side These legends indicate the current mode of the instrument and the scale of the data. The main window consists of two needles, one horizontal and one vertical. When in VEL or DIST mode, the horizontal needle indicates target-relative velocity or motion in the Y axis and the vertical needle indicates target-relative velocity or motion in the X axis. When in GRND mode, the horizontal needle reports forward velocity and the vertical needle reports lateral velocity.