A comment on melee weapons. Swords have always been pretty much scrapping the bottom of the barrel for armor. Against chain mail, if properly designed, they can be made to but against plate mail it's pretty much a no go. What they're really good at is against lightly armored opponents and in close quarters, like that present within a Roman shield wall with a Gladius.
If you want to penetrated with edged you really want an axe, and otherwize you're looking more at momentum weapons like a mace or hammer. Needless to say crossbows would defeat chain mail and even primitive black powder rifles firing literal ball could defeat plate mail. They were dumped in favor of muskets for more reasons then just the heat stroke, and difference in ability to reach out an touch someone.
Nowadays we use computer targetting on vehicles, with stabilized guns, and have much, much, much better bullet design. Of course, I should point out that stabilized on a block basically on the ground with 2 degrees of freedom isn't remotely the same issue as forcing it to work with a inherently unstable hanging position with at least four degrees of freedom. (arm up-down, arm forward-back, rotate x, rotate y)
Addendum:
Other design concerns with a bipedal mech:
-Any mecha firing an arm mounted weapon will need to both resist the linear recoil, the moment from their height ie y axis, and the moment from their center ie x axis. A conventional vehicle need only resist the linear recoil, and a much smaller moment from how high it is mounted.
-The bigger you are, especially vertically, the bigger a target you are because of the more obvious you aren't part of the landscape and how far out you can be spotted in general.
-The human form is extremely unaerodynamic, and any weight of the mecha itself would be dead weight. So if you want to fly you're basically going to have to do it space shuttle launch style, and given the space shuttle has the most efficient chemical rocket you're eithering going to have serious external tanks or serious internal volume taken up by stuff that'll blow up in a very big way.
-Seems as how if it's flying they'll conveniently putting up the equivalent of a 50 foot tall, blinking, billboard pointing at them, by putting out that kind of reaction mass even the simplest heatseeker will be able to nail them easily.
-Most of the human form is cylindrical in nature. Cylinder have the highest surface area to volume of any shape. More surface volume means that for the same internal volume you have more area to armor, which means for the same armor thickness more weight invested in armor. That's before we take into account things like the volume and weight necessary for a frame to support and move the limbs.
-Due to the nature of the joints you will either be limited in thickness so as to not compromise the range of motion, or have to deal with thin armor around the joints. A vital linkage, that can effectively disable the entire mech if damaged.
-Unlike a boxy more conventional AFV volume is spread out which limits the ability to use big engines, systems, etc. which you can't just spread through the mecha like you could metallic hydrogen or liquid oxygen tanks.
-Do to the vertical and dynamic nature of the mecha, in addition to other form issues, effective sloping of armor is unlikely. Most systems seen in anime would redirect the hit from the chest to the head , shoulders, arms, or waist none of which as as able to deal with damage as the chest should be.
-Unlike a conventional vehicle you can't really drive the locomation system directly off a ICE, diesel, or turbine arrangment in that you aren't just using gearing to transform turing of one shaft into the turning of another shaft. You could make it work eventually, but it's just not going to be as simple or direct. Seems as how most system would require electrical power, and other could use it fuel cell technology with battery would seem to possibly be the optimum approach. Nuclear power plants are basically just using the fission reaction to generate heat, and the normal approach while efficient are very heavy and bulky. Plus there are certain ethics issues. Hence why they're basically only on certain large non-front line Navy vessels and used for civilian powerplants. A RTG like used in a space craft while capable of providing extended power isn't going to provide the level of power you need, and volume on a mech is going to be critical.
If you want to penetrated with edged you really want an axe, and otherwize you're looking more at momentum weapons like a mace or hammer. Needless to say crossbows would defeat chain mail and even primitive black powder rifles firing literal ball could defeat plate mail. They were dumped in favor of muskets for more reasons then just the heat stroke, and difference in ability to reach out an touch someone.
Nowadays we use computer targetting on vehicles, with stabilized guns, and have much, much, much better bullet design. Of course, I should point out that stabilized on a block basically on the ground with 2 degrees of freedom isn't remotely the same issue as forcing it to work with a inherently unstable hanging position with at least four degrees of freedom. (arm up-down, arm forward-back, rotate x, rotate y)
Addendum:
Other design concerns with a bipedal mech:
-Any mecha firing an arm mounted weapon will need to both resist the linear recoil, the moment from their height ie y axis, and the moment from their center ie x axis. A conventional vehicle need only resist the linear recoil, and a much smaller moment from how high it is mounted.
-The bigger you are, especially vertically, the bigger a target you are because of the more obvious you aren't part of the landscape and how far out you can be spotted in general.
-The human form is extremely unaerodynamic, and any weight of the mecha itself would be dead weight. So if you want to fly you're basically going to have to do it space shuttle launch style, and given the space shuttle has the most efficient chemical rocket you're eithering going to have serious external tanks or serious internal volume taken up by stuff that'll blow up in a very big way.
-Seems as how if it's flying they'll conveniently putting up the equivalent of a 50 foot tall, blinking, billboard pointing at them, by putting out that kind of reaction mass even the simplest heatseeker will be able to nail them easily.
-Most of the human form is cylindrical in nature. Cylinder have the highest surface area to volume of any shape. More surface volume means that for the same internal volume you have more area to armor, which means for the same armor thickness more weight invested in armor. That's before we take into account things like the volume and weight necessary for a frame to support and move the limbs.
-Due to the nature of the joints you will either be limited in thickness so as to not compromise the range of motion, or have to deal with thin armor around the joints. A vital linkage, that can effectively disable the entire mech if damaged.
-Unlike a boxy more conventional AFV volume is spread out which limits the ability to use big engines, systems, etc. which you can't just spread through the mecha like you could metallic hydrogen or liquid oxygen tanks.
-Do to the vertical and dynamic nature of the mecha, in addition to other form issues, effective sloping of armor is unlikely. Most systems seen in anime would redirect the hit from the chest to the head , shoulders, arms, or waist none of which as as able to deal with damage as the chest should be.
-Unlike a conventional vehicle you can't really drive the locomation system directly off a ICE, diesel, or turbine arrangment in that you aren't just using gearing to transform turing of one shaft into the turning of another shaft. You could make it work eventually, but it's just not going to be as simple or direct. Seems as how most system would require electrical power, and other could use it fuel cell technology with battery would seem to possibly be the optimum approach. Nuclear power plants are basically just using the fission reaction to generate heat, and the normal approach while efficient are very heavy and bulky. Plus there are certain ethics issues. Hence why they're basically only on certain large non-front line Navy vessels and used for civilian powerplants. A RTG like used in a space craft while capable of providing extended power isn't going to provide the level of power you need, and volume on a mech is going to be critical.