Method for open-loop/closed-loop control of a robot joint driven by means of an electric motor, wherein the robot joint has a current sensor with first sensor electronics for detecting a first operating current i k, 1 (t) of the electric motor, with k = 1, 2,..., a first position sensor for detecting a drive position θ m ( t) of a drive train of the robot joint, a second position sensor for detecting a drive position q ( t) of a drive train of the robot joint, and a first torque sensor for detecting a torque τ J,1 ( t) in the drive train, wherein the electric motor is controlled in an open-loop/closed-loop manner based on a predetermined setpoint manipulated variable τ m ( t), having the following steps: - providing the measured values θ m ( t), i k, 1 ( t), τ J ( t), q ( t), - checking for the presence of an error by the first error detector, which detects the presence of an error if the measured values θ m ( t), i k,1 ( t), τ J ( t), q ( t) and/or their time derivatives do not meet predetermined first threshold conditions, and - checking for the presence of an error by the second error detector, which determines the presence of an error based on the measured values θ m ( t), i k,1 ( t), τ J ( t), q ( t) of a process model-supported method, wherein the process model is a predetermined mathematical dynamic model of the robot joint, and wherein an error is detected when parameters of the model, residuals between variables reconstructed by the process model and the measured variables and/or parameters determined internally in the model do not meet predetermined second threshold conditions, and - either providing the measured values τ J ( t) to a third error detector, which detects the presence of an error based on a signal-supported method, wherein an error is detected if signal variables, such as amplitudes and/or characteristic frequencies, of the measured values τ J ( t) do not meet predetermined third threshold conditions, or - determining a torque τ J,2 ( t) in the drive train with a second torque sensor or with redundantly designed sensor electronics of the first torque sensor and detecting an error by a fourth error detector if a comparison of τ J, 1 ( t) and τ J,2 ( t) does not satisfy fourth threshold conditions, and - if an error is detected by one of the available error detectors, producing a warning signal and/or controlling the electric motor with manipulated variables τ m F t, which move the robot joint to a predetermined error state FZ, and/or activating a mechanic mechanism for braking a movement of the robot joint. - providing the measured values θ m ( t), i k, 1 ( t), τ J ( t), q ( t), - checking for the presence of an error by the first error detector, which detects the presence of an error if the measured values θ m ( t), i k,1 ( t), τ J ( t), q ( t) and/or their time derivatives do not meet predetermined first threshold conditions, and - checking for the presence of an error by the second error detector, which determines the presence of an error based on the measured values θ m ( t), i k,1 ( t), τ J ( t), q ( t) of a process model-supported method, wherein the process model is a predetermined mathematical dynamic model of the robot joint, and wherein an error is detected when parameters of the model, residuals between variables reconstructed by the process model and the measured variables and/or parameters determined internally in the model do not meet predetermined second threshold conditions, and - either providing the measured values τ J ( t) to a third error detector, which detects the presence of an error based on a signal-supported method, wherein an error is detected if signal variables, such as amplitudes and/or characteristic frequencies, of the measured values τ J ( t) do not meet predetermined third threshold conditions, or - determining a torque τ J,2 ( t) in the drive train with a second torque sensor or with redundantly designed sensor electronics of the first torque sensor and detecting an error by a fourth error detector if a comparison of τ J, 1 ( t) and τ J,2 ( t) does not satisfy fourth threshold conditions, and - if an error is detected by one of the available error detectors, producing a warning signal and/or controlling the electric motor with manipulated variables τ m F t, which move the robot joint to a predetermined error state FZ, and/or activating a mechanic mechanism for braking a movement of the robot joint.