Automatic battery chargers only?

I’m reading rule R47 and it seems as if we are restricted to only automatic battery chargers. Does this mean that those teams with a lineup of manual ones now need to toss those and go buy new (expensive) auto ones? Why is there this rule?

My personal feeling is that teams should be able to pump juice into their batteries however they please (even if it be by hand crank generator) as long as it is safe. Well, maybe not that far but a manual battery charger is a commercial product designed by engineers for charging batteries, just like an automatic one. Why can’t we use it?

This has been answered before but I will try again. The rules specify the 4 amp or 6 amp smart chargers for several reasons. First and foremost, the battery manufacturer specifies that charging be no more that 6 amps. By using a smart charger you get maximum charge in the minimum time. All of the battery chargers supplied by FiRST over the years have been smart chargers so they know what to expect in terms of safety, speed, damage to batteries and humans, etc. when these devices are used at competition venues.
You might hear of teams that fast charge batteries at high currents but that is strictly illegal and must not be done at competition.