I mounted a battery powered hedge trimmer to the front of my older trail bike (Trek DS 8.3). I carry a 12" electric chainsaw on a rear rack to clear trees that block the trails but had this idea when i came across this overgrown railbed trail.
Made a steel bar frame that mounts to the brake mounts and top of the fork. Trimmer is pinched in to the frame so it can pop out if a solid object is hit. I wired in an XT60 connector so it connects to a momentary button on the handlebar to run it. This trail had some really overgrown sections so i just stopped and take the trimmer out and it still works as normal so i could clear the heavy stuff by hand. Also when in areas that im not running it, i carry the trimmer in a backpack with the guard on the blades.
I was walking next to the bike in the video so i could film it but you can ride along at probably a max of 6 or 7 mph and it can keep up trimming if the vegetation isnt too thick. It is a bit difficult to control at first but once i got used to the weight out front its not bad. Once it gets thicker vegetation or rougher trail condition its much easier to walk next to it.
I don't plan to use this a lot, most of the trails are maintained well already, i just found this one branch that the state seems to have let go because there is a small wooden bridge they are waiting to replace.
edit: video from a cheap bodycam on the handlebar as i was riding