A Camera and Laser System for Automatic Vine Balance Assessment

Canopy performance, the balance of crop weight and canopy volume, is a key indicator of value in viticultural production. Timely and dense measurement offer the potential to inform management practices and deliver significant improvement in production efficiency. Traditional measurement practices are labor intensive and provide sparse data that may not reflect vineyard variability. We propose and demonstrate a combination of visual and laser sensing mounted on vineyard machinery that provides dense maps of canopy performance indicators. Current industry practice for measuring grape crop weight involves manually counting clusters on a vine with destructive sampling to find the average weight of a single cluster. This paper presents an alternative utilizing vision and laser sensing. We demonstrate use of machine vision to automatically estimate the weight of the crop growing on a vine. Validation of the algorithm was performed by comparing weight estimates generated by the system to ground truth measurements collected by hand. Machine mounted laser scanners provide direct measurement of canopy shape and volume. Validation of the canopy volume measurement is provided by correlation with manually collected dormant vine pruning weight. Attaching these laser and camera sensors to vineyard machinery will allow crop weight and canopy volume measurements to be collected on a large scale quickly and economically. Experiments performed at vineyards growing Traminette and Riesling wine grapes and Concord juice grapes show that we were able to determine both crop weight and canopy volume to within 10% of their actual values.