The U.S. government and a group of global automakers are set to unveil a voluntary agreement at the Detroit auto show on Friday aimed at improving auto industry safety and spurring culture changes, according to company and government officials. The accord could set the framework for further discussions on safety reforms and mark a new era of cooperation between automakers and regulators after a record-setting year of safety fines, recalls and investigations into malfunctioning vehicles made by General Motors Co (GM.N), Fiat Chrysler Automobiles NV (FCAU.N), Honda Motor Co and others.