This is a concept drawing for a kind of minion. They have half human-level sentience. They can do everything and more an elite soldier needs to do but it can't hold a conversation other than the most basic pragmatic discussion of events and facts.
It wears a rubbery skin that has a basic painted on camouflage pattern that is similar to Multicam. It can also wear an exterior suit that has two reversible patterns. It's skin is bullet resistant to all small arms super sonic ballistics. It can also wear an exterior set of armor plates each of which has removable camouflage skins.
The index finger (fore finger) has a chemical scent sensor on the tip to allow the robot to smell. It it specifically tuned to detect human body odors and can distinguish between individual humans. It is also tuned to detect blood, urine, other excretory fluids, tobacco, rubber, shoe polish, gun powders, various explosives, poisons and other toxic substances.
There are several versions of this model, some are ruggedized for operation in specific environments. For example, the Tundra version specializes in cold, snowy, arctic environments with lots of precipitation and below-freezing temperatures. It's systems are internally heated to prevent cracking and stiffening. It's skin is insulated and infrared reflecting internally but not externally. It's skin is also specially tuned to remain supple and quiet even in -40 F temperatures. The Arrid version specializes in hot, sandy, desert environments. The Marine version specializes in over and under water operations, its skin is resistant to the ingress of salts and salt water. The Bog version specializes in swampy, wet, humid environments.
Each version has slightly different anatomical differences specifically designed to make the unit as best adapted for operation in their theater of specialty.
It runs on hydrogen fuel cells, the fuel is stored in carbon fullerene making it safe from explosion at any temperature. It has enough fuel to march on a perfectly flat track for 6 days with a full pack. It's full pack also includes a set of reserve fuel cells enough for 6 more days of operation. Its pack also contains a roll-out flexible solar panel that is 73 percent efficient and can replenish 100% of the on-bot fuel supply over a course of 2 sunny days.
During down time or other periods where physical movement is not required it can enter into an energy saving mode. It has a spectrum of energy-saving methods programmed into it.
The actuators are supple and flexible and mechanically similar to living muscle tissue. It is similar to air-muscle technology except these actuators use a kind of low density fluid to pressurize the actuators. These actuators can "lock" their pressure and do not consume any power at any position when the bot is still.
The parts that wear down due to abrasion and collision the most are the hands, elbows, outside of shoulders, the seat of the buttocks, knees, and the bottoms of the feet. These parts of the robot's exterior skin (and even some of their internal mechanical components) are designed to be easily and regularly replaced/maintained/repaired. The hands and feet in particular. The robot comes with "gloves" and "boots" that it perpetually wears. They are padded with especially tough but still supple material that absorbs more energy from collision, is more resistant to damage from abrasion, fire, heat, cold, salt water, vegetation, sand, and grit. These gloves and boots can be completely removed and replaced. And if replacements are not readily available, there is an extra base layer of protection built onto the robot's skin.