Autonomous Sensor Exchange and Calibration for Cornstalk Nitrate Monitoring Robot

TL;DR

This paper presents an autonomous system for sensor exchange and calibration on an agricultural robot, enabling reliable nitrate measurement in cornstalks with high success rate and minimal manual intervention.

Contribution

It introduces a novel gripper and replacement mechanism along with an on-board calibration station for autonomous sensor maintenance in crop monitoring robots.

Findings

Successfully inserted nitrate sensors into 30 cornstalks with 77% success rate.

Developed a reliable funneling design for efficient sensor exchange.

Integrated in-field calibration for consistent sensor measurements.

Abstract

Interactive sensors are an important component of robotic systems but often require manual replacement due to wear and tear. Automating this process can enhance system autonomy and facilitate long-term deployment. We developed an autonomous sensor exchange and calibration system for an agriculture crop monitoring robot that inserts a nitrate sensor into cornstalks. A novel gripper and replacement mechanism, featuring a reliable funneling design, were developed to enable efficient and reliable sensor exchanges. To maintain consistent nitrate sensor measurement, an on-board sensor calibration station was integrated to provide in-field sensor cleaning and calibration. The system was deployed at the Ames Curtis Farm in June 2024, where it successfully inserted nitrate sensors with high accuracy into 30 cornstalks with a 77$\%$ success rate.