Cooperative control design for nanorobots in drug delivery

All rights are reserved. In this chapter, we present cooperative control strategies for multi-robots to deliver drugs in tumor environments. We first discuss a nanorobot architecture, including chemical sensors, actuators, power supply, and data transmission, which is supported by the state of the art of nanotechnology. We then review tumor microenvironment modeling and pH measurement, where a tumor pH diffusion model is introduced and the pH value profile is established in the tumor environment. Based on the mathematical modeling, we propose a cooperative control strategy for pH sensitive nanorobots to deliver drugs in such environments. The control law is composed of gradient estimation and cooperative control, where the robots cooperatively estimate the gradient of the center of the group based on individual pH measurement, and then move towards the tumor center in a formation. We conduct rigorous convergence analysis and prove that the designed control steers the group of the robots reaching the cancer cells with the lowest pH value in the presence of estimation errors. Numerical simulations have shown effectiveness of the algorithm.