Weeds, or wild grasses, are naturally occurring grasses that grow in the wild without human cultivation. Weeds have detrimental effects on soil and crops, including competing with crops for space, nutrients, light, and moisture in the soil, which ultimately reduces crop productivity. Typically, herbicides are used to eliminate weeds, but all of these chemicals carry a potential threat to human well-being. This article presents a detailed plan for building a DELTA robot that is specifically engineered to eliminate weeds in agricultural environments. This article presents a systematic approach encompassing research, kinematics calculation, robot control, and the fabrication of a weed-killing robot prototype. The article proposes a prototype of a weed-killing robot with simple operation suitable for Vietnam's economic conditions. The experiments show that the robot can effectively remove different types of weeds from lettuce fields. The results show that the proposed prototype is completely capable of replacing humans, helping to improve productivity as well as protect health and help farmers avoid unwanted effects from herbicide chemicals.