Altitude-azimuthal mount for optical instruments

A method for controlling an alt-az mount, the method comprising:

• providing an alt-az mount for supporting and orienting optical instruments which comprises:
• a generally horizontally extending arm coupleable to a level surface by an azimuthal pivot joint which permits pivotal movement of the horizontally extending arm with respect to the level surface about a vertical azimuthal axis;
• a generally vertically extending arm pivotally coupled to the horizontally extending arm by an inter-arm pivot joint which permits pivotal movement of the vertically extending arm with respect to the horizontally extending arm about a vertical inter-arm axis;
• and
• an instrument coupling mechanism for coupling the mount to an optical instrument, the instrument coupling mechanism comprising an altitude pivot joint which permits pivotal movement of the optical instrument with respect to the vertically extending arm about a horizontal altitude axis;
• wherein the inter-arm pivot joint permits the mount to be adjusted between an inside configuration where the optical instrument and the azimuthal axis are located on the same side of the vertically extending arm and an outside configuration where the optical instrument and the azimuthal axis are located on opposite sides of the vertically extending arm;
• establishing inside altitude axis limits {altmin—in, altmax—in|altmin—in>0, altmax—in>0} on the movement of the altitude pivot joint when the mount is in the inside configuration such that an altitude angle (alt) is limited to a range −altmin—in≦alt≦altmax—in when the mount is in the inside configuration;
• establishing outside altitude axis limits {altmin—out, altmax—out|altmin—out>0, altmax—out>0} on the movement of the altitude pivot joint when the mount is in the outside configuration such that the altitude angle (alt) is limited to a range −altmin—out≦alt≦altmax—out when the mount is in the outside configuration, where altmin—out>altmin—in and altmax—out>altmax—in;
• and
• determining whether the mount is in the inside configuration or the outside configuration to thereby adjust between the first limits and the second limits.

An altitude-azimuthal mount for supporting and orienting optical instruments comprising:

• a generally horizontally extending arm coupleable to a level surface by an azimuthal pivot joint which permits pivotal movement of the horizontally extending arm with respect to the level surface about a vertical azimuthal axis;
• a generally vertically extending arm pivotally coupled to the horizontally extending arm by an inter-arm pivot joint which permits pivotal movement of the vertically extending arm with respect to the horizontally extending arm about a vertical inter-arm axis;
• and
• an instrument coupling mechanism for coupling the mount to an optical instrument, the instrument coupling mechanism comprising an altitude pivot joint which permits pivotal movement of the optical instrument with respect to the vertically extending arm about a horizontal altitude axis;
• wherein the inter-arm pivot joint permits the mount to be adjusted between an inside configuration where the optical instrument and the azimuthal axis are located on the same side of the vertically extending arm and an outside configuration where the optical instrument and the azimuthal axis are located on opposite sides of the vertically extending arm;
• and
• wherein the mount is a go-to mount comprising a controller for controlling movement of the altitude pivot joint and the azimuthal pivot joint and wherein the controller is configured to make use of inside altitude axis limits {altmin—in, altmax—in|altmin—in>0, altmax—in>0} which confine the angular range of controllable movement of the altitude pivot joint to altitude angles (alt) in a range −altmin—in≦alt≦altmax—in when the mount is in the inside configuration and to make use of outside altitude axis limits {altmin—out, altmax—out|altmin—out>0, altmax—out>0} which confine the angular range of controllable movement of the altitude pivot joint to altitude angles (alt) in a range −altmin—out≦alt≦altmax—out when the mount is in the outside configuration;
• and wherein altmin—out>altmin—in and altmax—out>altmax—in.

A method for controlling an alt-az mount, the method comprising:

• providing an alt-az mount for supporting and orienting optical instruments which comprises:
• a generally horizontally extending arm coupleable to a level surface by an azimuthal pivot joint which permits pivotal movement of the horizontally extending arm with respect to the level surface about a vertical azimuthal axis;
• a generally vertically extending arm pivotally coupled to the horizontally extending arm by an inter-arm pivot joint which permits pivotal movement of the vertically extending arm with respect to the horizontally extending arm about a vertical inter-arm axis;
• and
• an instrument coupling mechanism for coupling the mount to an optical instrument, the instrument coupling mechanism comprising an altitude pivot joint which permits pivotal movement of the optical instrument with respect to the vertically extending arm about a horizontal altitude axis;
• wherein the inter-arm pivot joint permits the mount to be adjusted between an inside configuration where the optical instrument and the azimuthal axis are located on the same side of the vertically extending arm and an outside configuration where the optical instrument and the azimuthal axis are located on opposite sides of the vertically extending arm;
• maintaining an altitude coordinate (alt) which is representative of the angular orientation of the altitude pivot joint about the altitude axis with a first polarity when the mount is in the inside configuration and maintaining the altitude coordinate (alt) with a second, opposing polarity when the mount is in the outside configuration;
• and.
• determining whether the mount is in the inside configuration or the outside configuration to thereby adjust the polarity of the altitude coordinate (alt).