As indicated in the title, the article of manufacture to which the ornamental design has been applied is a mobile robotic platform, also known as a mobile robot, mobile autonomous robot, robotic carrier or robotic transporter. The stippling in the figures represent a visible light effect, glow, or illumination, which is a part of the claimed design. Broken lines, within the claimed design, that depict recesses, gaps and/or protrusions on the surface of the mobile robotic platform in some embodiments, are for illustrative purposes only and form no part of the claimed design. Broken lines representing a robotic manipulator affixed to the top of the mobile robotic platform and wheels underneath the mobile robotic platform are also for illustrative purposes only and form no part of the claimed design.