Jt91 - 200 artillety gyro altazimuth is a fix instument which can research the grid north automatically and determine grid north azimuth at any direction . it works by making use of the physical features of gyro and influences of earth rotation . the equipment of this instument will play a important role in topographic clement Jt91 - 200型炮兵陀螺经纬仪是利用陀螺本身的物理特性和地球自转的影响，实现自动寻找其北方向和测定任一方向线的真北方位角的定向仪器。该型炮兵陀螺经纬仪的装备使用，对我军炮兵测地分队的测地保障发展将产生重大影响。
