Figure4

Figure 4. The observer-based PID team formation control of NCS of N satellites, where $$ u_{pid, i}(t) $$ denotes the PID control in (6), $$ u_i(t) $$ denotes the feedforward linearization reference control in (4) and $$ U_i(t) $$ is the actual control on the $$ i $$th satellite system from the actuator. $$ a_i(t) $$ and $$ s_i(t) $$ denote the actuator and sensor attack signals via a wireless communication network, respectively.