A method implemented on a digital radiography system, the DR system including an imaging device, and a computing device, the computing device including at least one processor and at least one storage device, the method comprising: directing multiple dose sensors to detect a dose of radiation rays emitted from a radiation source of the imaging device, wherein the multiple dose sensors correspond to multiple imaging detectors, respectively; determining the dose of the radiation rays detected by the multiple dose sensors; and directing, based on the dose of the radiation rays, at least one imaging detector from the multiple imaging detectors to proceed to detect the radiation rays for generating an image of a target object to be examined; characterized in that the method further comprises: $ determining whether more than one of the least one imaging detector is needed to detect the radiation rays; and in response to the determination that there is only one of the least one imaging detector needed to detect the radiation rays, obtaining a signal from the only one of the least one imaging detector; and generating the image of the target object based on the obtained signal; and in response to the determination that there is more than one of the least one imaging detector needed to detect the radiation rays, obtaining radiation data from the more than one of the at least one imaging detector; obtaining reference data associated with the target object; and generating the image of the target object based on the radiation data that is the closest to the reference data. directing multiple dose sensors to detect a dose of radiation rays emitted from a radiation source of the imaging device, wherein the multiple dose sensors correspond to multiple imaging detectors, respectively; determining the dose of the radiation rays detected by the multiple dose sensors; and directing, based on the dose of the radiation rays, at least one imaging detector from the multiple imaging detectors to proceed to detect the radiation rays for generating an image of a target object to be examined; characterized in that the method further comprises: $ determining whether more than one of the least one imaging detector is needed to detect the radiation rays; and in response to the determination that there is only one of the least one imaging detector needed to detect the radiation rays, obtaining a signal from the only one of the least one imaging detector; and generating the image of the target object based on the obtained signal; and in response to the determination that there is more than one of the least one imaging detector needed to detect the radiation rays, obtaining radiation data from the more than one of the at least one imaging detector; obtaining reference data associated with the target object; and generating the image of the target object based on the radiation data that is the closest to the reference data. determining whether more than one of the least one imaging detector is needed to detect the radiation rays; and in response to the determination that there is only one of the least one imaging detector needed to detect the radiation rays, obtaining a signal from the only one of the least one imaging detector; and generating the image of the target object based on the obtained signal; and in response to the determination that there is more than one of the least one imaging detector needed to detect the radiation rays, obtaining radiation data from the more than one of the at least one imaging detector; obtaining reference data associated with the target object; and generating the image of the target object based on the radiation data that is the closest to the reference data.