Even with the many recent advances in robotics technology, the vision that many people have in their heads of lifelike, humanoid robots is still far from becoming a reality. While engineers are able to design robots to perform a variety of increasingly complex tasks, the challenge posed by the design and creation of human-like robots is yet to be tackled. If robot technology is advancing at such a rapid pace, why is the creation of humanoid robots such a challenge?

On a design level, there are many issues with humanoid robots that prove very difficult to solve. For one, the human body is an incredibly complex system, and things that come without thinking to people require detailed programming and research to approximate with robots. Humans actually use many more than the five most well-known senses to navigate the world; chief among these is something called “proprioception”. This sense is probably something you’ve never thought of before, but that is actually very important to human movement; this is what allows you to move parts of your body without observing them directly. For example, even if you can’t see your feet as you read this, you still know where they are in relation to the rest of your body.

Even if roboticists could figure out how to perfectly replicate all of the senses people use to move around, the physical technology required to create a functional humanoid robot still doesn’t exist. To simulate human motion, robots rely on hundreds or even thousands of “actuators” - machine parts that move parts of the robot back and forth. In addition to the fact that robots would need a very large number of actuators to achieve the same range of motion as people, there are two key issues with actuators themselves that make this difficult. First, actuators can either be very powerful, or very precise, but rarely both. While humans can lift heavy objects and also perform careful operations with the same muscles, robot actuators cannot. Second, actuators require quite a lot of power to function, and the larger the battery, the stronger (and heavier) the actuators need to be to support it.

Despite the many challenges, companies are working hard to create humanoid robots, like Honda’s ASIMO or Toyota’s THR-3. While they may seem unattainable now, with the pace that robotics technology is developing at, we may only be one breakthrough away from the robots of the future.