Yes, It's a cobbled together rear Bendix Red Band hub with the fork spread, the fork axle slots enlarged, a brake arm attachment welded onto the fork, a spring to bring the hub back and the ball inside the hub welded shut so it wouldn't rotate so the brake would grab right away. Didn't work very well as you could not get enough leverage with a hand brake. I tried different brakes levers, long pull and short pull. The long pull pulled further but then the force is reduced. It barley scrubbed off any speed. It was a head scratcher for people who saw it. The frame was made from a girls bike and an old cheap mountain bike rear triangle. Homemade seat post too. I finally broke the frame riding single track, but it lasted all summer.
So as I was thinking before - rear hubs used as front roller brakes - not a great idea And yet I thought I was onto something...