Low-cost Indirect Measurement Methods for Self-x Integrated Sensory Electronics for Industry 4.0

Abstract

The conventional method for testing the performance of reconfigurable sensory electronics of industry 4.0 relies on the direct measurement methods. This approach gives higher accuracy but at the price of extremely high testing cost and does not utilize the new degrees of freedom for measurement methods enabled by industry 4.0. In order to reduce the test cost and use available resources more efficiently, a primary approach, called indirect measurements or alternative testing has been proposed using a non-intrusive sensor. Its basic principle consists in using the indirect measurements, in order to estimate the sensory electronics performance parameters without measuring directly. The non-intrusive property of the proposed method offers better performance of the sensing electronics and virtually applicable to any sensing electronics. Efficiency is evaluated in terms of model accuracy by using six different classical metrics. It uses an indirect current-feedback instrumentation amplifier (InAmp) as a test vehicle to evaluate the performance parameters of the circuit. The device is implemented using CMOS 0.35 μm technology. The achieved maximum value of average expected error metrics is 0.24, and the lowest value of correlation performance metrics is 0.91, which represent an excellent efficiency of InAmp performance predictor.

Low-Cost Indirect Measurements for Power-Efficient In-Field Optimization of Configurable Analog Front-Ends with Self-X Properties: A Hardware Implementation

“…To minimize the impact of random occurrences or lucky shots, the optimization process was performed for 10 independent runs on the chip marked as number 1. Comprehensive information on the optimization algorithm can be found in [37,63]. The mean value of the error-convergence curve for the optimization algorithm is illustrated in Figure 21.…”

“…This approach is unsuitable when the power of different optimization solutions must be evaluated. The authors of [63] proposed an alternative technique for indirectly estimating the CFIA DC power. As illustrated in Figure 5 with the green-colored components, this method relies on mirroring scaled-down values of currents from the power-intensive branches into the current-starved ring oscillator [64].…”

Integrated Sensor Electronic Front-Ends with Self-X Capabilities

“…Compared to the optimization of digital evolvable hardware such as the field-programmable gate array (FPGA), the optimization of evolvable analog circuits at the transistor level may result in harmful solutions in terms of excessive currents that could cause a permanent failure of the DUT or reduce its life cycle. To alleviate this issue and enhance the long-term reliability, we recently embedded the low-cost indirect power monitoring module (PPM) with THD-based optimization methodology [173], as shown in Figure 14. The PPM serves two essential functions.…”