I personally don't know if it did - I've never seen any information on operator safety of this machine, though I have read a lot about it and Ralph Mosher over the years.

He's also the guy behind the GE Hardiman exoskeleton:

https://en.wikipedia.org/wiki/Hardiman

...which was another system much like this truck. For that one - and I don't know how true it was - it was said that it could get into a feedback loop that could cause injuries to the user, but it wasn't clear if that was for the entire "suit" or for the mounted arm test assembly (they had built a single arm up to the shoulder and mounted it on a stand to test it separately from the "suit").

GE was heavily into this field of what they called "man amplifiers" - several of the later ones spearheaded by Mosher:

http://cyberneticzoo.com/man-amplifiers/1953-g-e-o-man-manip...

http://cyberneticzoo.com/man-amplifiers/1958-9-ge-handyman-r...

http://cyberneticzoo.com/walking-machines/1962-64-ge-pedipul...

http://cyberneticzoo.com/man-amplifiers/1965-g-e-lifting-boo...

http://cyberneticzoo.com/teleoperators/1969-g-e-man-mate-ind...

This was also the same time period as Hughes Aircraft's MOBOT systems - which were meant as remote manipulators for working in nuclear research, underwater repaid, and similar harsh environments:

http://cyberneticzoo.com/teleoperators/1959-mobot-1-hughes-a...

http://cyberneticzoo.com/teleoperators/1962-underwater-mobot...

http://cyberneticzoo.com/teleoperators/1963c-mobot-hughes-ai...

http://cyberneticzoo.com/teleoperators/1964-%e2%80%93-mobot-...

What we now know as "ROVs" (and UAVs, UGVs, and other names) all stem from a lot of this research back then (and earlier). Hughes' system was actually kind of innovative; there is a paper you can dig up (in fact, I think it's linked on one of the above articles) that detail how these systems were controlled:

They needed to control a lot of various servo and other actuators, but they couldn't use a long cable with tons of wires - they needed the cable to be flexible and not weigh a ton (which is still an issue today). But they didn't have the modern electronics we have today to accomplish it. What they ended up doing was using a synchronized motor-switching system that had two rotary switches driven by synchronous motors on both ends. There was a mechanism in place to keep them "in sync" so that the switch connected on one end would be the same as on the other end. The controller at the transmitter would thus be connected to the proper motor or actuator at the other end, many times a second, and the umbilical only needed a few wires (plus wires for power - which IIRC was AC and served as part of the sync system - plus wires for video feeds). In a way, it was an early form of electro-mechanical multiplexing.

It quickly gave way to more electronic methods (likely things more closely resembling serial PPM, used in hobby radio control systems - once reliable transistors became common; while such a thing could have been done with vacuum tubes, it wouldn't have been reliable on such machines and environments) - but reading that paper was an interesting insight on how to do things differently! In fact, it's similar in scope to how Westinghouse did something similar for telemetry monitoring and control back in the 1920s and 30s - and showcased in their "robot" Electro - by using sounds and tuning forks, in a similar was to electrical coherer systems - they could control relays remotely using tones sent down telephone lines. Why Hughes didn't use a similar approach is a mystery - could have been patent reasons, or reliability issues or something of that nature.

It's a fascinating period of history in robotics, control theory, computation, and more in my opinion (also at this time, you have a large interest going on in artificial intelligence - such as it was in those years - and deep behind the scenes, there was certain interest in so-called "artificial neurons" - hardware implementations of the McCulloch-Pitts neuron model. At one time, around 1956 IIRC, RCA even made a "frog's retina" model using similar models - when you look at it and how it was wired and works - it really looks like a CNN made of hardware for image recognition...