The performance of the zero-effort-miss/zero-effort-velocity feedback guidance algorithm is evaluated through practical space application examples. The zero-effort-miss/zero-effort-velocity feedback guidance algorithm is, in general, not an optimal solution; however, it is an optimal solution in a uniform gravitational environment. It is also conceptually simple and easy to implement and, thus, has great potential for autonomous onboard implementation. It is shown that, for some classic ballistic missile intercept and asteroid intercept scenarios, the zero-effort-miss/zeroeffort-velocity algorithm can even compete with corresponding open-loop optimal solutions, while its feedback characteristics make it more suitable to deal with uncertainties and perturbations. By employing the zero-effort-miss/ zero-effort-velocity algorithm in the highly nonlinear orbital transfer and raising problems and comparing with corresponding open-loop optimal solutions, its simplicity and near-optimality are further verified
