A Hydromechanical Method for Converting Hydrostatic Pressure into a Binary Code Using Weighted Hydraulic Pressure Thresholds and Binary Search

Conventional reservoir-level measurement systems convert hydrostatic pressure into an electrical signal, which makes the entire sensing chain dependent on electronic components that are vulnerable to lightning-induced transients, power interruption, and long-term environmental degradation. This paper proposes a hydromechanical measurement architecture in which hydrostatic pressure is converted directly into an n-bit digital code through a purely mechanical successive-approximation procedure, with no electrical component anywhere in the sensing or comparison chain. A lever-balance comparator, pivoting on a knife-edge, is weighed against a reference column fed by a bank of individually calibrated, laminar-flow binary-pressure orifices; a fixed manual protocol, structurally identical to the classical single-pan binary-weight problem, halves the search interval at each of n steps, resolving the most significant bit first. A Monte Carlo simulation propagating a physically-derived, bit-dependent orifice calibration-retention error, differential fluid-density mismatch, and comparator friction through the full binary-search procedure identifies a practical operating point of n = 10 bits, giving an effective resolution of approximately 1.4 mm (7.7 effective bits) over a 1.024 m bench-scale range. The architecture extends our prior demonstration that the successive-approximation principle is independent of the specific physical quantity involved, showing here that it is also independent of the electrical domain altogether.