Long-range magnetic tracking

Abstract

Two magnetic trackers are described in this paper. The first one is fully magnetic and has 1 meter range. This device can measure distance with 1 mm resolution and 1 cm total accuracy. The second system is a hybrid tracker using active magnetic ranger, three optical gyros and three micromachined inclinometers. It has 15 m range and for distances below 5 m the position accuracy is 50cm. The heading error is below 0.1 deg. .

Precise Magnetic Sensors for Navigation and Prospection

“…The position of the drill pipe is calculated by dead-reckoning algorithm employing orientation information (azimuth, pitch, and roll) from accelerometers and magnetometers and length information from the drill string length measurement. Due to the limited accuracy of magnetic sensors and accelerometer, the position estimation accuracy is also limited [20]. When dead-reckoning algorithm is used in such application, the error propagates with distance as shown in Table 1 depending on accuracy of heading sensor.…”

“…The magnetic field data measured by the magnetometer are compared to the magnetic source model, and the position of the magnetometers is then calculated with respect to the source. We introduced an intersection system in the study of Ripka et al [20] with two excitation coils in the first drill head and two fluxgate magnetometers in the second drill head. The source magnetic moment was m = NAI = ±89 Am 2 .…”

Convex optimization of measurement allocation for magnetic tracking systems

“…For example, magnetic tracking has been used for eye tracking to diagnose Ménière's disease , positioning of wireless capsule endoscopes within the gastro-intestinal tract (Yang et al 2009), real-time organ-positioning during radiotherapy of cancer tumors (Iustin et al 2008), catheter tracking (Krueger et al 2005;Biosense Webster 2011), monitoring of heart valve prostheses (Baldoni and Yellen 2007), tongue movement tracking (Gilbert et al 2010;Wang et al 2013), tracking of lung segment movements (Leira et al 2012), and positioning of bone-embedded implants (Sherman et al 2007). Examples of non-medical applications of magnetic tracking include head tracking for helmet-mounted sights in military aircraft (Raab et al 1979), underground drilling guidance (Ripka et al 2012), augmented and virtual reality (Liu et al 2004), and tracking of the ball during an American football game (Arumugam et al 2011).…”