The panels in transit will and must remain flat, none of the tilting crap is going to be worth anything unless the trailer is still. Any added wind resistance will render them useless or even impractical while the trailer is motion, The trailer is needed for cargo food and stuff so the even with the added weight of the panels is still a win win situation. They are very light for the power they actually produce so it is a viable pursuit.
Preliminary test have indicated on a sunny bright day with max exposure they can double your range of a 12ah 36v pack in a 4 to 5 hour charging period in winter Queensland Australia.
Battery voltage did drop after a long run in my day but would soon enough bump back up to around 12.8v in 20 mins or so per 12v SLA. The panels are always assiting when the bike is in use.
In series my panels provide 66v and at battery terminal voltage of 39v produce 1.4 amps of current up to 51v. A regulator is needed but I havent run into this situation where panels will over charge the pack yet.