Sensor concept for solving the direct kinematics problem of the Stewart-Gough platform

On the Direct Kinematics Problem of Parallel Mechanisms

“…However, we have shown in [29] that, by also including the information about the yaw orientation of the manipulator platform, the direct kinematics problem of -6 mechanisms can be uniquely solved. In the following, we will review our solution concept from [29] in the context of a general -mechanism with , ∈ {3, . .…”

“…In [29], we used the InvenSense MPU-9150 inertial measurement units (IMUs) consisting of an acceleration sensor with three axes, a gyroscope, and a magnetic sensor for determining the closed-form solution for the direct kinematics problem of a general -mechanism. We obtained the correct solution for selected static poses, but the results showed relatively high mean errors and standard deviations, especially for the yaw orientation of the manipulator platform.…”

“…Another problem related to calibration is sensor placement. In [29], we mounted the IMUs on the gearboxes of the linear actuators and on top of the manipulator platform. In this context, the alignment of the IMUs regarding the base platform's coordinate system has to be determined very carefully.…”

“…As already mentioned above, we tested our approach for the general -mechanism on several static poses [29]. In the static case, the acceleration sensors measure the constant gravity vector of the earth without any disturbances.…”

“…The orientations of the linear actuators and the roll-pitch orientation of the manipulator platform can be measured, for example, by acceleration sensors with three axes, and the measurement of the yaw orientation of the manipulator platform can be realized, for example, by using a magnetic sensor [29]. The remainder of this paper is organized as follows.…”