Aspects of the present disclosure are presented for a surgical instrument having one or more sensors at or a near an end effector and configured to aide in the detection of tissues and other materials and structures at a surgical site. The detections may then be used to aide in the placement of the end effector and to confirm which objects to operate on, or alternatively, to avoid. Examples of sensors include laser sensors used to employ Doppler shift principles to detect movement of objects at the surgical site, such as blood cells; resistance sensors to detect the presence of metal; monochromatic light sources that allow for different levels of absorption from different types of substances present at the surgical site, and near infrared spectrometers with small form factors.