A wearable module for recording worker position in orchards

This paper describes the design and testing of a wearable position recording system for workers in orchards or in protected cultivation environments, where GPS data are typically unavailable. The major goal of the wearable system is to track worker position in relation to trees. This system consists of a pedometer and a small barcode reader and utilizes barcode tags permanently attached to fixed objects of known location (e.g., individual trees in an orchard). The pedometer computes a worker’s relative displacement with respect to a known starting position, and the barcode provides the absolute (starting) position information at regular intervals to keep the localization error at an acceptable level. Evaluations of the accuracy and reliability of the pedometer revealed a 2–3% accumulated error in the estimation of the worker’s position. The use of the pedometer alone was insufficient and could not establish correctly the association between trees and workers. The prototype system was implemented and tested during manual harvest in two commercial peach orchards. The fruit pickers’ movements were captured accurately and the association between producing tree(s) and fruit picker, as well as the sequence of the trees which the picker visited, were established correctly.

► A wearable position recording system for workers in orchards is introduced.
► The system consists of a pedometer and a small barcode reader.
► This system tracks worker position in relation to trees/plans.
► The sequence of the trees visited by the worker was established correctly.
► The time the workers spend to each tree would be calculated for management purpose.