An irrigation controller mechanically actuated by soil-water tensions: I - design, development and laboratory evaluation - Almeida, Alexsandro C. S; Botrel, Tarlei Arriel; Raine, Steven R; Camargo, Antonio Pires de; Pinto, Marinaldo Ferreira; Salvador, Conan Ayade (Revista Brasileira de Engenharia Agrícola e Ambiental, 2017)