Procesiranje signalov magnetometrov v vztrajnostni merilni enoti

Kač, Katja (author), Kutin, Jože (mentor), Svete, Andrej (co-mentor)

Vztrajnostna merilna enota se uporablja pri navigacijskih sistemih oz. orientaciji v prostoru. Ta meri v vseh treh oseh koordinatnega sistema posebej pospeške, kotne zasuke ter magnetno polje. Za natančno meritev položaja je potrebno podatke iz vseh zaznaval združiti. Vztrajnostna merilna enota sama po sebi ne izvaja korekcije z magnetometri in ne omogoča meritve odklona od magnetnega severa. V primeru vpliva zunanjih motenj (železo, elektromagnetno polje, itn.) je magnetno polje popačeno ter ima magnetno deviacijo, katero je potrebno izničiti. Korekcijo zanj smo izvedli tako, da smo napisali program, ki ta odmik izniči. Ta si podatke v času vrtenja zapomni, jim izriše povprečno elipso (saj podatki pridejo v obliki elipse) in elipso na koncu premakne na središče koordinatnega sistema, jo rotira in transformira v enotsko krožnico. Tako smo dobili matriko, preko katere izvajamo korekcijo odklona od magnetnega severa.

• Language: Slovenian
• Keywords: vztrajnostna merilna enota, korekcija, magnetometeri, magnetno polje, trdno-železni učinek, mehko-železni učinek, programska koda, vključek
• Work type: Bachelor thesis/paper
• Typology: 2.11 - Undergraduate Thesis
• Organization: FS - Faculty of Mechanical Engineering
• Place of publishing: Ljubljana
• Publisher: [K. Kač]
• Year: 2022
• Number of pages: XX, 44 str.
• PID: 20.500.12556/RUL-135323
• UDC: 681:537.612+004.415.25(043.2)
• COBISS.SI-ID: 101181699
• Publication date in RUL: 08.03.2022

Secondary language

• Language: English
• Title: Processing of magnetometer signals in an inertial measurement unit

Abstract

The inertial measurement unit is used in navigation systems or for orientation in space. It measures accelerations, angular rotations and the magnetic field in all three axes of the coordinate system. Data from all the sensors need to be combined to obtain accurate position measurements. The inertial measurement unit itself does not perform corrections with magnetometers and does not enable measurements of the deviation from the magnetic north. When influenced by external disturbances (iron, electromagnetic field, etc.) the magnetic field becomes distorted and has a magnetic deviation that needs to be eliminated. We therefore designed a program that eliminates this deviation. The program remembers the data received during the rotation of inertial measurement unit, draws the average ellipse (since the data are obtained in the form of an ellipse) and finally moves the ellipse to the centre of the coordinate system, rotates it and transforms it into a unit circle. That is how we got a matrix through which we perform corrections of the deviation from the magnetic north.

• Keywords: inertial measurement unit, correction, magnetometer, magnetic field, hard-iron effect, soft-iron effect, program code, plugin