Are advances in medical robotics making surgeries more precise and safer, and can high-degree-of-freedom robotic arms surpass human limitations?

Advanced robotics technology is revolutionizing the medical field beyond its efficiency in the industrial workplace. Robotic arms with high degrees of freedom are enabling more precise and safer surgeries that go beyond human limitations. These technological advances are expanding the possibilities for medical robots and providing a safer surgical environment.

 

The development of advanced computers and advances in mechanical engineering have led to the introduction and expansion of robots in various industries to improve efficiency and reduce costs. In particular, the use of industrial robots is expanding beyond just manufacturing. Robotic technology has evolved to perform increasingly complex tasks, and these advances have revolutionized the healthcare industry as well. In fact, robots that were initially only used in large-scale manufacturing processes are now entering the medical field and playing an important role in precise tasks such as surgery. This is just one example of how fast technology is advancing.
The use of robots in healthcare became highly researched and practical in the 1990s. At that time, many doctors and engineers worked together to develop robots that could perform more sophisticated surgeries. After several generations of medical robots, we’ve now reached the fourth generation of the da Vinci robot, which is beneficial for surgery for prostate, rectal, esophageal, and bladder cancers, which can have severe side effects and complications if the surrounding nerves and blood vessels are damaged during surgery. This is because the da Vinci robot’s arm has a higher degree of freedom than a human arm. But what is a degree of freedom, and why is it an advantage in surgery?
In robotics, degrees of freedom (DOF or Mobility) is the number of independent variables that can minimally represent the state of an object. This concept is essential to understanding the complex issues involved in robot movement. To simplify things a bit, you can think of degrees of freedom as representing the flexibility of movement. If we introduce a Cartesian coordinate system into this space, the only ways the object can move are translational motion along the x, y, and z axes, and rotational motion around the x, y, and z axes. Any combination of these six motions can be used to describe the motion of an object, and each motion (e.g., rotation about the x-axis) is called one degree of freedom. In other words, an unconstrained object in space has six degrees of freedom. This concept is very important and is considered essential in the design and use of real-world robotic arms.
So, how many degrees of freedom do two objects connected by pins have? We’ve discussed degrees of freedom above, but the answer isn’t immediately obvious. The problem becomes even more dizzying when you add dozens more objects and pins to the mix. To calculate the number of degrees of freedom in such a complex structure, anyone who has studied robotics will recognize Grübler’s formula. This formula is an important tool for understanding complex structures and is often utilized in the process of designing and evaluating robots.
In robotics, an object is called a link, and the pin that connects two links is called a joint. Joints constrain the two links, reducing the object’s degrees of freedom. Different types of joints have different degrees of constraint, and therefore different degrees of freedom. In any case, the general idea is that links increase the number of degrees of freedom and joints decrease them, and the Gribbler’s formula is based on this idea. For any structure, no matter how complex, you can find the degrees of freedom of an object by substituting the appropriate number of links, the number of joints, and the number of degrees of freedom reduced by the type of joints in the structure into Grubler’s formula. These calculations are not just a theoretical exercise, but are essential for the design and operation of robots in real-world industrial and medical applications.
These degrees of freedom give us an idea of how flexible an object can be, and how much power it needs to move in order to achieve that degree of freedom. If an object has one degree of freedom, it can only move in one direction, but if it has two, it can move in two directions. In general, one degree of freedom requires one motor. This is because one motor is responsible for rotation or translational motion in one direction. The relationship between the number of degrees of freedom and the number of power units is very important in the design of a robot, and only the right combination of these elements will allow the robot to operate efficiently in the real world.
The human arm typically has seven degrees of freedom. This is because the calculation assumes that the wrist or shoulder can rotate in all directions, although not a full 360 degrees. However, a robotic arm can have more than 7 degrees of freedom by adjusting the number of links and joints, and the wrist of a robotic arm can rotate 360 degrees unlike a human. This allows for more flexible movement than humans, which is where robotic arms shine in fields such as medical surgery, where precise work is required. This increase in degrees of freedom also allows the robot to operate in more complex environments. However, as mentioned above, one degree of freedom requires one power unit, so it is important to properly design a robot arm that balances the number of degrees of freedom required in the field with other practical constraints such as weight, manufacturing cost, and power. This is not just a theoretical issue, but a major challenge in developing robotic systems that can be implemented in practice.