Steerpike is correct. Titanium is not magnetic. And magnetic boots will not simulate any sense of gravity. It will be like running inb 1/3 gravity on a layer of fresh tar. Feet will stick in contact with the floor, but people will sail through the air when neither foot is anchored. In corridors, exxpect a lot of concussions. Also broken bones at corners. Inertia is unaffected by gravity.
How about your martians simply have a kind of "weight" in their feet that anchors them? Or some sort of natural hook that's part of their feet that helps them dig into the ground with every step (think football shoes!)? This could be a physical mutation to adapt to its natural environment where gravity is lacking. Or have your martians build a society with, as you say, gravity machines that ONLY run within the city - but once you venture outside you'll sail through the atmosphere for lack of gravity. Thus the machine only has limited power and was invented for the sole purpose of survival - this would make sense because the area within which it affects is very limited.
crap... youve found the hole. screw it. they have grav-boots now. and its a human colony. there are no martians. or native martians, if you want to be politically correct.
Again, I have to ask why. Grav boots, at best, will simulate earth gravity for the character's feet. The rest of his body will experience 1/3 gee, like a bottom-weighted punching balloon. Why not make the reduced gravity a challenge to deal with, instead of jumping through hoops to make it seem like Earth-normal? It isn't as if you have to shoot a TV series or a movie and save on your special effects budget. I see absolutely no benefit to creating a one gee environment, either to you as a writer, or to the humans building or bringing expensive or bulky equipment.
alright i see what you mean. It could be fun to write a chase seen in 1/3 earth gravity. CHALLENGE ACCEPTED. I dont know why i wanted Mars to have regular gravity, probably because we haven't tested the long term effects of low G's on the body. That way it saves the characvters from having to go to the gym daily. Gravity would make things seem easier on Mars. Most sci fi movies always have a grim look on colonist life. Take Outland for instance, that was a very depressing atmosphere to live on a mining vessel. I figured that with mars you would have to exercise, youd live in the side of a mountain, youd mine iron and silicon and your life would suck, and youd lose bone density. I'd say gravity would be there only connection to earth, that way it wasnt so depressing. low g would get old after a while. Therefore, i needed a semi logical solution that would take a two sentence explanation as to why there were close to normal Gs on Mars.
