Fusion of Data from Quadcopter’s Inertial Measurement Unit Using Complementary Filter

A quadcopter is a helicopter with four rotors, which is mechanically simple device, but requires complex electrical control for each motor. Control system needs accurate information about quadcopter’s attitude in order to achieve stable flight. The goal of this bachelor’s thesis was to research how this information could be obtained. Literature review revealed that most of the quadcopters, whose source-code is available, use a complementary filter or some derivative of it to fuse data from a gyroscope, an accelerometer and often also a magnetometer. These sensors combined are called an Inertial Measurement Unit. This thesis focuses on calculating angles from each sensor’s data and fusing these with a complementary filter. On the basis of literature review and measurements using a quadcopter, the proposed filter provides sufficiently accurate attitude data for flight control system. However, a simple complementary filter has one significant drawback – it works reliably only when the quadcopter is hovering or moving at a constant speed. The reason is that an accelerometer can’t be used to measure angles accurately if linear acceleration is present. This problem can be fixed using some derivative of a complementary filter like an adaptive complementary filter or a Kalman filter, which are not covered in this thesis.

A Diachronic Study of the Practises of Translation of Gerunds and Gerundives from Latin into Old English and Middle English in History Narratives

This is a philologically oriented thesis which studies the possible adoption of a grammatical feature from one language into another from historical linguistic perspective. The foci of the study are, on the one hand, the Latin gerund and gerundive and, on the other hand, the English gerund. The material of this study consists of excerpts from two British history narratives in Latin and from the Old English and Middle English translations of these history narratives. The British history narratives selected for the material of this thesis are the 8th century Historia ecclesiastica gentis Anglorum by Bede and the 14th century Polychronicon by Ranulf Higden. Historia ecclesiastica gentis Anglorum has been compared with its Old English translation from the 11th century, the author of which is unknown. The Polychronicon, on the other hand, has been compared with two different Middle English translations: one from the 14th century, by John Trevisa; the other from the 15th century, the author of which is also unknown. The purpose of this thesis is to investigate whether the gerund, which was adopted into English by the Middle English period, has been used to translate the Latin gerunds and gerundives. At the basis of the study is the hypothesis that the English gerund has been used to translate the Latin gerunds and gerundives at least occasionally. The methodology of this thesis consists of detailed and qualitative study of the primary material. The primary material has been studied from synchronic, diachronic and paratextual perspective. The results of this thesis confirm that the English gerund has occasionally been used to translate the Latin gerunds and gerundives. The instances that confirm with the hypothesis are so rare, however, that the relationship between the English gerund and the Latin gerund and gerundive seems to be indirect or at least enshadowed by wide-ranging grammatical differences.