Autonomous vehicle control requires estimating vehicle states from on-board sensor readings. In the case that some of the sensors are compromised, the state of the vehicle may not be accurately estimated. The goal of this Clinic project is to implement a secure state estimator (SSE) in simulation and then validate it in hardware on a low-cost quadrotor. The team will demonstrate that the addition of the SSE to the control loop reduces the real-time tracking error of a quadrotor when using measurements from compromised onboard sensors.