Soil strength testing and collecting soil cores from wetlands is currently a slow, manual process that runs the risk of disturbing and contaminating soil samples. This paper describes a method using an instrumented dart deployed and retrieved by a drone for performing core sample tests in soft soils. The instrumented dart can simultaneously conduct free- fall penetrometer tests. A drone-mounted mechanism enables deploying and reeling in the dart for sample return or for multiple soil strength tests. Tests examine the effect of dart tip diameter and drop height on soil retrieval, and the requisite pull force to retrieve the samples. Further tests examine the dart’s ability to measure soil strength and penetration depth. Hardware trials demonstrate that the drone can repeatedly drop and retrieve a dart, and that the soil can be discretely sampled.
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Assessment of Soil Strength using a Robotically Deployed and Retrieved Penetrometer
This paper presents a method for performing free-fall penetrometer tests for soft soils using an instrumented dart deployed by a quadcopter. Tests were performed with three soil types and used to examine the effect of drop height on the penetration depth and the deceleration profile. Further tests analyzed the force required to remove a dart from the soil and the effect of pulling at different speeds and angles. The pull force of a consumer drone was measured, and tests were performed where a drone delivered and removed darts in soil representative of a wetland environment.
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- NSF-PAR ID:
- 10219786
- Date Published:
- Journal Name:
- 2020 IEEE/RSJ International Conference on Intelligent Robots and Systems (IROS)
- Page Range / eLocation ID:
- 7324 to 7329
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Conference Paper:
- https://doi.org/10.1109/IROS45743.2020.9341424
