Cross-point resistive arrays are attractive for high-density tactile sensing because they reduce wiring complexity. However, conventional frequency-based readout methods can become inaccurate in robotic sensing environments, where long interconnects and measurement and environmental noise degrade the observed signals. We propose a time-domain optimization method for robust readout of cross-point resistive arrays. The method determines resistance values by fitting a time-domain observation model to the measured waveform over the interval, rather than relying solely on spectral amplitudes. By exploiting the full waveform, the proposed method improves robustness under noisy observation conditions. In simulations of a 16 x 16 array, the proposed method reduced the mean readout error by 20% compared with the baseline method. Furthermore, validation over 1,000 trials showed that the proposed method achieves more robust estimation than the conventional method, reducing the mean error and standard deviation by 24.6% and 77.6%, respectively. The improvement was also confirmed in cross-point array simulations with resistance distributions emulating tactile sensor responses.
Taro Tako, Takanori Jin, Hiroshi Kaminaga, Taisuke Kobayashi
原文摘要
Variable stiffness mechanisms that achieve both flexibility and rigidity are important technologies for robotic systems. Recently, wire-based jamming mechanisms have attracted significant attention. In the wire-based jamming mechanisms, modules are chained by a wire, and the overall stiffness is controlled by changing the friction between the modules through wire tension. These mechanisms have been widely studied due to their simple structure and controllability. However, conventional wire-based jamming mechanisms mainly focus on holding torque along the joint axis, and the resistance against disturbances in other directions has not been sufficiently explored. In this study, we propose a wedge-jamming mechanism that introduces wedge-shaped contact surfaces into the modules of wire-based jamming structures. By changing the wedge angle, the holding characteristics against disturbances in different directions can be adjusted. Experimental results show that an out-wedge configuration improves resistance to vertical disturbances, while an in-wedge configuration enhances resistance to torsional disturbances. These results demonstrate that the anisotropic holding performance of wire-based jamming mechanisms depend on wedge geometry.