This project discusses and implements the estimation of Residual Link Lifetime (RLL) in Mobile ad-hoc Networks (MANETs) using the distances between various link nodes within the network. In this report, a Mobile-Projected Trajectory (MPT) algorithm is proposed, which employs periodic measurements of the distances between the nodes to estimate the relative trajectory between them. The RLL of the link between the two nodes is then predicted using this relative trajectory. A Velocity-Change Detection (VCD) test is used to further enhance the MPT prediction to counter changes in relative velocities of the nodes. The accuracy in the RLL prediction for multiple velocity variations is shown through performance evaluations. Simulation results show the effectiveness with which the proposed algorithm operates and also demonstrates a significant improvement in performance over prevailing algorithms.