Closed circuit cameras could be used. Such systems are now offered on Range Rovers, giving the driver views all around the vehicle on a split screen display in the cabin to see where rocks and potholes are, and to see over crests when negotiating rough and hilly terrain. There's no reason why similar systems should not be adopted on HGVs and the costs need not be huge. Of course, those responsible for crashes with HGVs are usually unthinking, inconsiderate car drivers.