Self-Calibration of Accelerometer Arrays (SCARS)

• Applicant: Professor Dr.-Ing. Yiannos Manoli
• Subject Area: Measurement Systems
• Term: from 2014 to 2019
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 258832626

An inertial measurement unit (IMU) determines the relative motion of a body in the form of its transversal acceleration and its angular velocity. Conventionally, an IMU comprises three accelerometers and three gyroscopes. In contrast to this, a gyroscope-free inertial measurement unit (GF-IMU) detects the relative motion based on acceleration measurements only. Thereby, multiple transducers attached at distinct locations within the body jointly form an accelerometer array. To accurately estimate the relative motion, the sensor poses, i.e., their positions and orientations, must be known precisely. However, those are often only available with an insufficient accuracy. Hence, they are commonly reconstructed by calibration. Current state of the art calibration methods determine the geometrical sensor configuration based on a set of motion data and corresponding acceleration measurements. Sophisticated laboratory equipment is thus required to impose a reference motion on the sensor array, which results in additional costs for each produced measurement unit. Moreover, the equipment is mostly not suitable for sensor arrays with large geometrical dimensions, which inhibits a calibration for many applications. The goal of this research project is to create a self-calibration method for accelerometer arrays. Thus, the accelerometer poses are determined using only their own measurements without any external reference. Moreover, the derived method is intended to work on an arbitrary motion, such that it can be applied during the normal operation of the GF-IMU. To achieve these goals we will investigate how to introduce inherent knowledge about the measurement system to a numerical optimization of the sensor poses. The resulting methodology is not specific to accelerometer arrays and thus has the potential to be adopted for other measurement systems.

• DFG Programme: Research Grants