This paper presents a self collision detection scheme for humanoid robots using elliptical and circular capsules as bounding volumes. A capsule is defined as an elliptical or circular cylinder capped with ellipsoids or spheres respectively. The humanoid body is modeled using elliptical capsules, while the moving segments, i.e. arms and legs, of the humanoid are modeled using circular capsules. This collision detection model provides a good fit to the humanoid body shape while being simple to implement. A case study of the self collision free workspace of the humanoid arm is then presented to illustrate the effectiveness of the collision detection scheme.

Model Predictive Control (MPC) has received wide attention from both the academic and industrial societies, mainly in the chemical industries, and is fast gaining popularity in Electro-Mechanical industrial systems. Great success stories of applications of MPC to industrial systems have been reported. However, the model based nature of this control methodology raises numerous questions of robustness, mainly towards prediction accuracy. A large amount of research has been conducted in MPC tuning, both mathematically inclined and heuristic. However, most of the works were intended at improving performance and robustness for control systems that are not interconnected over shared networks. In this paper, analysis of the standard tuning parameters of MPC and their effects on prediction accuracy are investigated, implications of such accuracy on Networked Control Systems (NCS) with random data packet dropouts are demonstrated by simulation and experimental studies.

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Electrical Impedance Tomography (EIT) has been dominated by the use of Time Division Multiplexing (TDM) and Frequency Division Multiplexing (FDM) as methods of achieving orthogonal injection of excitation signals. Code Division Multiplexing (CDM), presented in this paper is an alternative that eliminates temporal data inconsistencies of TDM for fast changing systems. Furthermore, this approach eliminates data inconsistencies that arise in FDM when frequency bands of current injecting electrodes are chosen over frequencies that have large changes in the imaged object's impedance. To the authors knowledge no fully functional wideband system or simulation platform using simultaneous injection of Gold codes currents has been reported. In this paper, we formulate, simulate and develop a fully functional pseudo-random (Gold) code driven EIT system with 15 excitation currents and 16 separate voltage measurement electrodes. In the work we verify the use of CDM as a multiplexing modality in simultaneous injection EIT, using a prototype system with an overall bandwidth of 15 kHz, and attainable speed of 462 frames/s using codes with a period of 31 chips. Simulations and experiments are performed using the Electrical Impedance and Diffuse Optics Reconstruction Software (EIDORS). We also propose the use of image processing on reconstructed images to establish their quality quantitatively without access to raw reconstruction data. The results of this study show that CDM can be successfully used in EIT, and gives results of similar visual quality to TDM and FDM. Achieved performance shows average position error of 3.5% and size error of 6.2%.

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