90-year-old David Resnick ran an outfit called United Inventors and Scientists which loved to help inventors. In fact, he helped the inventor of this spring-mounted cradle right out of the photo, and right out of the 1974 LA Times feature article it ran with.
But I do know that that 2yo kid they stuck in the cradle, Jose Crespo, is too big for it, and that as soon as he stood up, that whole thing'd topple over and faceplant him on the workshop's concrete floor.
And now that I bought this old photo, I do know that that car battery underneath it is, in fact, NOT connected to the cradle, but to the dismantled pedal car behind it.
And if I had to guess who invented this rig, I'd go with Frank Grosse, of Glendale, who got a patent for a very similar design, a design that also, amazingly, had casters. Because, why not, right? How else you gonna move that thing around? People so crazy.
Except, Grosse filed his patent in 1960, and it was granted in 1963. And it was a spinoff of an earlier patent for a spring-mounted hobby horse that Grosse filed in 1959 with Charles Barnes.
So what kind of help Resnick was providing 14 years later, either to the original inventor or to a guy who thought he'd just invented it, I have no idea.