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A front-end loader (FEL) mounted on an agricultural tractor is one of the most commonly used implements for farm work.However, when the tractor carries loads with the front-end loader on hills, it can be dangerous if the bucket is high and its angle is not tilted properly depending on variable slope angles.The control of the bucket angle using a manual spool valve has a limitation in effectively maintaining the bucket angle within a constant level while timely responding to a change in ground slope under rough terrain conditions.This study was conducted to develop an active self-leveling system that could automatically maintain the bucket angle at a safe level based on the real-time measurement of tractor tilting angle in order to eliminate the risk of rollback on sloping ground.An embedded self-leveling system consisting of real-time processing hardware and virtual electronic control units (ECU)s was mounted on a 65-kW agricultural tractor with an electro hydraulic control valve to investigate the feasibility of using the developed system for safe movement of the tractor with loads on sloping ground.In the laboratory tests, the bucket angle of the FEL simulator was successfully changed to reach the target values when two different step inputs, i.e., +20° and-20° under different bucket loads were imposed.In the field tests, the embedded self-leveling system showed the ability to maintain the bucket angle at an angle of 0 deg at three different slope levels, i.e., 0%, 15% and 18%,