公开(公告)号：US5519318A

公开(公告)日：1996-05-21

申请号：US997043

申请日：1992-12-28

申请人： Steve J. Koerner ,  Anthony E. Lifur ,  Michael J. Wall

发明人： Steve J. Koerner ,  Anthony E. Lifur ,  Michael J. Wall

IPC分类号： G01C17/30 ,  G01R33/02

CPC分类号： G01R33/0206 ,  G01C17/30

摘要： A triaxial magnetic heading sensing apparatus includes nulling coils and netoresistive sensors having inputs and outputs. The nulling coils are arranged in parallel relation to three orthogonal planes intersecting at a common center point. The sensors are disposed along orthogonal axes in parallel relation to the orthogonal planes and in close proximity to the center point. Each sensor has a bridge configuration balanced in the absence of an applied external magnetic field and unbalanced in the presence one. Also, a signal generator is connected to the inputs of the sensors for exciting the sensors with a bipolar voltage waveform exhibiting alternating positive and negative voltage polarities punctuated by "off" states of zero volts. Further, a voltage integrator and low pass filter are connected in series with the output of a respective one of the sensors for generating an error signal representative of an imbalance due to the presence of an applied external magnetic field and for coupling the input and output of each nulling coil and of each sensor into a servo control loop such that each sensor is driven by the error signal to a magnetic nulling condition with zero steady state error. A pick-off resistor is connected to the output of the low pass filter for outputting a representation of the nulling current to provide a measure of the applied external magnetic field.

摘要翻译： 三轴磁头检测装置包括具有输入和输出的零线圈和磁阻传感器。 零点线圈与在共同中心点相交的三个正交平面平行地布置。 传感器沿正交轴线平行于正交平面并且靠近中心点设置。 每个传感器在没有施加的外部磁场的情况下具有平衡的桥接配置，并且在存在的情况下不平衡。 此外，信号发生器连接到传感器的输入端，用双极性电压波形来激励传感器，该双极性电压波形呈现由零电压“断开”状态标记的正和负电压极性。 此外，电压积分器和低通滤波器与相应的传感器的输出串联连接，用于产生由于存在施加的外部磁场而导致不平衡的误差信号，并且用于耦合输入和输出 每个零线圈和每个传感器分成伺服控制回路，使得每个传感器由误差信号驱动到具有零稳态误差的磁零点状态。 接通电阻器连接到低通滤波器的输出端，用于输出归零电流的表示，以提供所施加的外部磁场的测量值。