An assembly and a method for entering a lateral branch of a main wellbore through a lateral window with an assembly are described. The assembly includes an arm coupled to a body. The arm positions the body to enter the lateral branch. The assembly includes an actuator to actuate the arm relative to the body. The assembly includes a first sensor, a second sensor, and a controller. The first sensor senses a condition of the arm and transmit the condition of the arm to the controller. The second sensor senses when the assembly is located in the main wellbore or the lateral branch transmits the location to the controller. Responsive to either the first signal or the second signal, the controller actuates the arm relative to the body to position the body to enter the lateral window and determines when the assembly has entered the lateral branch.