▁control ▁unit ▁as ▁a ▁real ▁plant ▁can ▁create ▁the ▁following ▁dangerous ▁conditions ▁for ▁the ▁test ▁engineer : ▁ ▁Test ing ▁at ▁or ▁beyond ▁the ▁range ▁of ▁the ▁certain ▁EC U ▁parameters ▁( e . g . ▁Engine ▁parameters ▁etc .) ▁ ▁Test ing ▁and ▁ver ification ▁of ▁the ▁system ▁at ▁failure ▁conditions ▁In ▁the ▁above - ment ioned ▁test ▁scenarios , ▁H IL ▁provides ▁the ▁efficient ▁control ▁and ▁safe ▁environment ▁where ▁test ▁or ▁application ▁engineer ▁can ▁focus ▁on ▁the ▁functionality ▁of ▁the ▁controller . ▁ ▁T ight ▁development ▁sched ules ▁ ▁The ▁tight ▁development ▁sched ules ▁associated ▁with ▁most ▁new ▁autom ot ive , ▁a eros pace ▁and ▁defense ▁programs ▁do ▁not ▁allow ▁embedded ▁system ▁testing ▁to ▁wait ▁for ▁a ▁prototype ▁to ▁be ▁available . ▁In ▁fact , ▁most ▁new ▁development ▁sched ules ▁assume ▁that ▁H IL ▁simulation ▁will ▁be ▁used ▁in ▁parallel ▁with ▁the ▁development ▁of ▁the ▁plant . ▁For ▁example , ▁by ▁the ▁time ▁a ▁new ▁autom obile ▁engine ▁prototype ▁is ▁made ▁available ▁for ▁control ▁system ▁testing , ▁ 9 5 % ▁of ▁the ▁engine ▁controller ▁testing ▁will ▁have ▁been ▁completed ▁using ▁H IL ▁simulation . ▁ ▁The ▁a eros pace ▁and ▁defense ▁indust ries ▁are ▁even ▁more ▁likely ▁to ▁imp ose ▁a ▁tight ▁development ▁schedule . ▁A ircraft ▁and ▁land ▁vehicle ▁development ▁programs ▁are ▁using ▁desktop ▁and ▁H IL ▁simulation ▁to ▁perform ▁design , ▁test , ▁and ▁integration ▁in ▁parallel . ▁ ▁High - bur den - rate ▁plant ▁ ▁In ▁many ▁cases , ▁the ▁plant ▁is ▁more ▁expensive ▁than