OpenCHIRP: A Low-Cost, Lightweight Sub-Bottom Profiler for Shallow Water Environments Suitable for Autonomous Vehicles

Highlights: What are the main findings? Development of an innovative sub-bottom profiler for acquiring seismic reflection data in shallow-water environments. Key characteristics: low cost, lightweight, and compatible with autonomous vehicles. What are the implication of the main findings? Extensive use of open hardware and software, with code and assembly instructions provided in the article. Enables seafloor and subseafloor pseudo-3D and 4D (repeated) mapping. This paper presents the development of OpenCHIRP, an innovative sub-bottom profiler (SBP) designed for high-resolution seismic reflection surveys in shallow-water marine and lacustrine environments. The instrument employs chirped (frequency-modulated) impulses to penetrate the first few meters of unconsolidated sediments below the seafloor. Key characteristics include low cost, light weight, and low energy consumption, making it particularly suitable for deployment onboard Autonomous Surface Vehicles (ASVs). We discuss design, functionality, and potential applications of this innovative instrument, as well as results of the preliminary tests.