History of Robotic Legs and Arms: How Far We Have Come

You have seen Will Smith chase down bots in “I, Robot” and Arnold in his cyborg swagger in The Terminator.

Closer to home, perhaps you’ve visited a Tesla factory on a field trip and found numerous robotic arms relentlessly assembling the electric supercar.

Perhaps, you saw a little Roomba hovering over the floor at your friend’s place, and now you desire a friendly, household “pet.”

The nuances of automation and human motion simulation intrigued me so much as a child that I considered taking up mechanical and automation engineering as a career path.

I soon realized that robots are a complex amalgamation of human anatomy, electrical and mechanical engineering, nanotechnology, medicine, etc.

However, that did not stop them from becoming integral to our social fabric, the scientific community, and even pop culture.

Moreover, we find several instances of robots and full automation in modern times, but the concept’s origins go back to ancient Greek philosophers.

Robotic arms form the foundation of utility in a robot as they are programmable and versatile.

So, while tracing the history of robotic arms, we can go back to Leonardo Da Vinci’s first automated version, to advancement during the World War, finally leading up to George Devol’s invention of the first fully automated arm.

Soon, the sophistication of robotic arms led to the development and integration into cinematography, animation, production, and most importantly, prosthetics.

I couldn’t find a concise article or blog that could tell the entire story, and sate my curiosity.

So, I compiled the article as a documented journey that you can read along to find out how far we have come in science and technology.

Leonardo Da Vinci’s Robot Arm

Da Vinci’s creative prowess was not confined to paintings and sculpting, as he dared to walk the fine line between art and engineering.

While he famously conceptualized the Ornithopter as his vision of a flying machine, he wasn’t too far off from building the first humanoid robot.

Da Vinci started by designing a programmable front-wheel-drive automobile that could control its direction and motion.

The design never saw the light of production, but it featured technology that was centuries ahead of its time.

Da Vinci’s focus drifted towards a deeper understanding of human anatomy paired with metal works, drafting, armor design, etc., while dedicating his time to painting and sculpting.

Research undertaken by the Institute and Museum of the History of Science in Florence indicates that his first robot imitated basic human motion using two independent systems –

  • The lower body, including the legs, ankles, knees, and hips, which possessed three degrees of freedom
  • The upper body with the arms had four degrees of motion

So, we’re talking about a programmable robot that could grasp items, sit up, and move its jaw in the late 15th Century.

Da Vinci also dabbled in designing mechanical birds and a lion, which were still a long stretch from prototyping, but set the tone of full automation for the future.

However, Da Vinci was not a pioneer of stimulated mechanical motion.

He derived inspiration and knowledge from ancient Greek scholars long before him, who pursued the idea of mechanical engineering and human attributes.

Detailed descriptions and drawings from the 1,119 pages of Da Vinci’s notebook, called the Codex Atlanticus, have become a cornerstone of modern-day robotics.

Automata in the Early Industrial Revolution

Do images from Chaplin’s Modern Times and men in top hats in carriages pop in your head when you think about the Industrial Revolution?

Indeed, despite all its perils, the era showed the world what a modern-day factory and human labor could appear. Standardization and mass production were the primary objectives. 

However, what often gets lost in translation is the innovation and advancements made in technology during the time.

Also, a mere mechanical engineer may have sparked the Industrial Revolution and made substantial progress in clockwork automata.

Jacques de Vaucanson, like Da Vinci, pursued his interest in anatomy and medicine as he designed a pipe-and-drum player and a mechanical duck.

His contrivances came to significance in 1738, as he put together a mechanical flutist called the “Androde” (interestingly).

The sight of wires and steel chains working together to imitate the motion of fingers similar to any living man opened up endless possibilities in automata. 

Soon after Vaucanson’s conquest into stimulated mechanical movement, a Swiss-clock-making family undertook three life-sized automata projects that simulated human anatomy.

For instance, their robotic musician could play the clavichord using their fingertips.Similarly, Wolfgang von Kempelen constructed his mechanical chess player, called the Turk, in 1769.

Before you assume that the Turk used AI to play chess, you should know the idea was more of a gimmick –

  • The chess players had an automated left arm in its wood-carved figure, draped in Turkish garb.
  • It could move its neck and eyes tucked inside sockets.
  • A pantograph (or “director”) drove the left arm movements while residing in its chest.
  • It could pick the desired chess piece and move it to the desired square.
  • Each finger had a distinct wired connection to the pantograph.

Kempelen’s prototype chess players possessed limited degrees of freedom, but it envisioned the possibility of emulating human reason and animation.

World’s Fair Robots

It is hard to talk about Robots without talking about the war. But history fails to credit the impact of expositions during a time without the World Wide Web or even television.

Expositions showcased advancements made in science and technology worldwide, and they invoked the idea to transform human lives.

The first industrial one took place in Paris in 1798. Still, it was not until 100 years later that the world witnessed the unveiling of remote-controlled robotic devices at the Madison Square Garden exposition.

Nikola Tesla piqued an unsuspecting audience with a demo of the first fully automated, remote-controlled submerged boat.

It caused quite the stir in the scientific community, but soon the world was distracted by war.

So, 37 years after Madison Square Garden, the San Diego Exposition brought to light a 2,000-pound mechanical man called Alpha as a marvel of automation and human motion simulation.

The robot could sit, roll its eyes, stand, and even fire a gun! While it did not garner enough popularity, the one at New York World’s Fair two years later certainly made some noise.

Named Elektro, it could respond to English commands (Alexa?) and undertake more complex tasks than any robot before.

It could move on the stage and used a 78-rpm record player to engage in conversation, powered by a 700-word strong vocabulary.

Elektro quite literally rose to stardom following the World’s Fair as he went on to feature in a B-movie.

Robots Post World War II

Now, robots were certainly a reality, and the masses started taking notice.

But they still lacked refinement as they consisted of loud electrical motors and vacuum tube relays in the early to mid-20th Century.

Soon after the Second World War, tech innovation accelerated as we started exploring microcircuits and solid-state transistors. 

Eventually, the robotics scene blew up entering the 21st Century, and the 2005 World’s Expo held in Aichi, Japan, made it evident.

Visitors caught a glimpse of working robots that hovered over the ground and performed routine activities such as child-care duties or garbage collection.

The world witnessed multiple prototypes of different robots over the 11-day expo, with an entire station dedicated to it.

Big corporations such as Toyota, Mitsubishi, and Brother Industries took center stage to present their vision of robotics in the future, validating the immense potential in the field.

George Devol and the first Modern Robotic Arm

If I had to single out a game-changer in consumer electronics market growth, I would say it’s the transition from vacuum tubes to transistors.

We had already conceptualized automation and robots. Now, it was possible to sophisticate it with microelectronics.

Willard Pollard patented the first position controlling mechanism with five degrees of freedom and an electrical control system, but he could not manufacture it.

However, he inspired Harold A. Roselund to refine mechanical movement by mobilizing each joint in unique ways.

Yet, the technology was not marketable as the electrical control system lacked fidelity.

Thus, George Devol and Joseph Engelberger entered the scene with Unimate – the first industrial arm installed at General Motors, Ternstedt, New Jersey.

Unimate used nautical terms such as pitch, roll, and yaw to describe degrees of movement in the arm.

Engelberger went on to start a company, Unimation, to market and sell the Unimate. He successfully sold 8,500 units until Kawasaki acquired the manufacturing rights.

Robot Arms Today and How they are Designed

So far, you may have noticed how the history of robotics focuses on getting a robotic arm to work.

Among all the parts going into building a functional robot, the arm stands out as the critical one.

It is the manipulator that performs a specific task.

You still need a motor for motion and sensors for detection, but you cannot have an industrial robot without a robotic arm.

Similar to human anatomy, we can break down the robotic arm into five components –

  • Shoulder – links the arm to the main skeleton of the industrial robot and possesses the highest load-bearing capacity
  • Elbow – Joint that allows flexible motion, including extension, reaching, angular movement, or retraction
  • Wrist – end portion of an arm that performs the actual task with the help of different end-effectors
  • End-effector (hand) – similar to fingers and meant for fine adjustments in handling tasks

The number of joints determines the axes of a robotic arm. Hence, the productivity and flexibility of a robotic arm improve with the number of joints.

Modern-day robots take the robotic arm and enhance its automation with controllers and sensors.

Hence, the main components that go into building a robot are –

  • Robotic arm – The main functional unit of a robot, which performs the actual task
  • End-effectors – Part of the robotic arm which are attachments based on the task at hand. For instance, it is fingers meant for gripping or a drill bit.
  • Motors – The driving force behind robotic motion, consisting of actuators powered by electrical, pneumatic, or hydraulic energy.
  • Sensors – Electronic devices that detect and measure parameters and trigger a reaction based on them. For instance, sensors can detect obstacles and change the course of a robotic arm’s motion.
  • Controller – A closed-loop system that includes programming and computing to read and execute commands and retain instructions in the memory.

Animatronics for Entertainment

Taking a break from robots in industries, they have also found in a home in entertainment and recreation.

We have extensively discussed the utility of robots, but what purpose would a life-sized animated mechanical T-Rex serve? Nothing but a good time in a theme park.

Animatronics revolutionized puppetry with the introduction of mechatronic puppets.

You can find one at Disneyworld or Futuroscope, imitating natural muscle movements using computer logic or manual control, including remote control.

The robot has a skeletal frame, usually made of steel for support, and a foam rubber or silicone skin. Latex is a popular option for masks and facial prosthetics.

Motion modeling involves the use of pneumatic actuators for small movements and hydraulics for larger designs.

Animatronics has found a way to celluloid, the most famous being the recreation of dinosaurs from Jurassic Park without the use of entirely CGI.

Robotic Arms in Manufacturing

Robotic arms have found limitless potential in manufacturing. Industrial production relies heavily on scalability and standardization within the least possible time.

Hence, it involves performing highly labor-intensive and repetitive work without compromising on precision or quality.

Designing the appropriate robotic arm for the right purpose forms the first step of automation in manufacturing.

It can be a mundane pick-and-place job such as on a conveyor belt; or, it may involve manufacturing intricate circuit boards, such as chipsets.

Here are the different facets to consider while designing a robotic arm for manufacturing –

  • Load – Robotic arms can do the heavy lifting up to a fixed load capacity, which should exceed the weight of the payload involved in production. 
  • Speed – The automated task improves throughput significantly, but getting the speed and acceleration right becomes crucial when traversing long distances.
  • Precision – It is essential for several sophisticated processes, but given its expense, bulk jobs may see it as overkill.

Apart from deciding the technical aspects, robotic arms in manufacturing are also subjected to rough environments and potential hazards.

They endure more wear and tear than an average general-purpose robot.

Hence, it is necessary to premeditate the duration between resting the robotic arm and servicing it to extract optimum efficiency from it.

Robotic Arms in the Cinematography

Robotic Arms are used to film complex scenes that involve precise camera movement. From rigs to autonomous robotic arms.

The advent of robotic arms meant the expansion of the cinematic canvas. 12 Angry Men may have been a classic shot in a single room, but we can’t imagine the same for the Lord of the Rings trilogy.

Travel and precision over long ranges meant cinematographers could play with unique angles, including more aerial shots or pan the camera seamlessly for a car chase.

Modern cinematographers swear by motion-controlled camera setups, which use multiple robotics arms to translate and rotate the camera as freely as possible.

We can equip a camera-wielding robotic arm to sync with the speed of fast-moving objects or capture a high-speed macro.

Moreover, cinematography and robotics have intertwined to give us rigs and cinema robots (such as KIRA) that do not restrict a scene to steady or shaky cam.

Software controls the arm to snap back and forth between positions while capturing perfectly stable frames.

Robotic Arms Used in Space to Conduct Repairs

Again, robots and automation allow us to perform tasks that would otherwise seem impossible (even potentially kill us). Space exploration would be one such domain.

How else would we know about the terrain on Mars if it wasn’t for NASA’s PathFinder?

Robotic arms find extensive use in space technology –

  • It can transfer payloads in and out of the ISS
  • Transfer cargo
  • Release satellites
  • Repair damages
  • Automate repetitive tasks

So, when it comes to refueling, fixing, or upgrading space tech, robotic arms bring speed and precision to the table.

Researchers and engineers are looking at the prospect of satellite servicing using a robotic arm to reduce redundancy in building new equipment each time.

It also brings down the carbon footprint, and satellites can stay afloat for longer durations.

Prosthetic Limbs: Robotic Legs and Arms

I feel the best way to understand the complexity behind prosthetic limbs is to break down a mundane everyday human motion – taking a sip from a cup of coffee.

Think about the neural and muscular interactions that go into it –

  • You put your arm down to position it with the cup handle
  • You curl your finger around the handle in the correct orientation, with the thumb on top
  • You need to get the pressure right to ensure you can lift the cup and avoid spilling any coffee
  • With the cup in your grasp, you move it towards your mouth for a sip
  • All the while, you need to maintain the pressure on the cup handle

Hence, if you begin breaking down simple activities, they are more than muscle memory.

A prosthetic leg or arm does not possess that memory, so it needs to follow an algorithm.

It poses a challenge to recreate that seamless motion of grabbing a cup of coffee or itching your nose, which comes naturally to an able human being.

However, advancements in material science have unlocked a superpower potential to create bionic prosthetic limbs that mimic physical ones.

The concepts of bionic limbs may seem similar to creating a Cyborg, but we are closer to that reality than ever.

While research and development will not cease, we have come a long way in creating lighter, efficient, and affordable options using electronics, hydraulics, nanotechnology, and medicine.

Myoelectric limbs

Traditionally, upper-body prosthetics relied on body movement to manipulate cables connected to the limb.

It proved to be a full-blown workout to move your arm than natural motion.

Myoelectric limbs harness power from batteries instead of physical movement and use an electronic system to direct motion.

Here’s how it works –

  • On attachment, sensors on the prosthetic limb detect nerve endings, synapses, and muscles from the remaining portion of the body part.
  • The muscle activity from the body is sent to the skin at the point of attachment.
  • The data gets forwarded to microprocessors which process it to control the limb.

So Myoelectric limbs operate on the physical and mental stimulus triggered by the user.

Instead of the user actively controlling the prosthetic, it acts more naturally with control over strength, grip, and speed.

Alternatively, touchpads or rockers can also control myoelectric limbs.

We can achieve more dexterity to perform finer activities with an increased number of sensors in the limb attachment.

Osseointegration

While Myoelectric limbs utilize sensors and signals, Osseointegration makes direct contact between a bone and an implant.

The procedure is more surgical as the titanium-based implant is physically connected to the remaining part of the limb through an opening in two stages –

  1. Insertion of the implant into the bone with some soft-tissue revision
  2. Refinement of the stoma (opening) after six to eight weeks and fixing the implant to the external prosthetic leg.

Eventually, bone and muscle cover the implant, forming a fully functioning bionic leg.

It offers an array of benefits in terms of stability and control over the prosthetic.

Moreover, since it’s direct contact, it eliminates the suction suspension needed in Myoelectric limbs and improves the overall comfort of the prosthetic.

Companies today that work on Prosthetic Limbs

The idea behind prosthetic research is to restore the quality of life for an individual following disease or trauma.

Hence, companies are moving towards blurring the lines between mechanical and natural bodily motion.

For instance, a team of engineers and scientists at John Hopkins’ Applied Physics Laboratory produced the Modular Prosthetic Limb, replicating human strength and appearance with an anthropomorphic form factor.

It can precisely sense position and packs a neural interface for closed-loop control.

Similarly, the BiOM T2 developed at MIT is an ankle-foot prosthetic that emulates muscle movement with programmable microprocessors and sensors.

It runs on battery power, which can operate for close to five million steps, and users can recharge it after.

Ottobock has been a market leader in supplying prosthetics and wheelchairs for Paralympians, and they hold about 1,886 patents for technical innovations in the field.

They aim to optimize an athlete’s performance by designing specific prosthetics to fit their needs while complying with competitive fair play.

So, a significant challenge for the prosthetics industry was the fit. Limbs are not worth it if they don’t fit the user’s body type and shape.

That is where 3D printing and CAD have opened up the possibility for custom-fit prosthetic limbs which can be affordable and anatomically accurate.

The prostheses can be personalized to mirror the user’s complexion, complete with freckles, birthmarks, veins, hair, etc. So, you won’t be able to tell a prosthetic arm or a leg from a real one.

While the limb is made of PVC or silicone, it is draped in adhesive, form-fitting, or stretchable skins to appear more realistic. 

Prosthetics in the Paralympics

Prosthetics in sports enhance our perception and understanding of bionic limbs and their future.

For instance, Johannes Floors sprints for up to six hours for training and holds the world record in the 200m sprint. He is a double amputee.

Prosthetics in Paralympics require a specific design suited for a particular sport to bring the most out of an athlete.

Here are some of the prosthetic legs that you will come across in the games –

  1. 1E91
  2. Pro Carve Sport Prothesis
  3. 3S80 Sports Joint
  4. Flex-Foot Cheetah

Moreover, prosthetics do not qualify as doping in any form. The games disallow the use of electronics in prosthetics.

The International Paralympic Committee (IPC) documents how each disability affects performance and, subsequently, how to create a level-playing field for everyone.

Armed with Knowledge

Robotic arms are now integrated into a multitude of fields.

It is not limited to manufacturing and production, as it finds extensive use in medical science, labs, testing, and sampling, or purely for entertainment.

We have successfully mass-manufactured fully automated robotic arms.

So, the next step is to build smart mechanical arms and develop intelligent machines that automatically control engineering and manufacturing.

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Frequently Asked Questions

How much does the robot arm cost?

Industrial robot arms can cost anywhere between $25,000 to $400,000. You can find a basic one with seven degrees of freedom for $5,000.

In addition to the cost of the arm, users will also need to account for the controller, end of arm tooling (EOAT), and any particular software.

What are the typical 5 components that make up the robotic arm?

The five components that make up a robotic arm are –

  • Controller
  • Sensors
  • Robotic arm
  • End effector
  • Driver (Motor)

What is a robotic arm made of?

The structural framework for a robotic arm is made of durable materials, such as cast iron or steel. Prosthetic arms or animatronics may add a PVC or silicone layer over the skeleton.

Who invented robotic arms?

George Devol invented a working model of the first robotic arm, called Unimate. Joseph Engelberger marketed the product, and it was first installed at the General Motors plant in Ternstedt, New Jersey.

How good are robotic arms?

  • Robotic arms are fast and can traverse long distances repeatedly to perform repetitive tasks without tiring 
  • They are accurate and precise, with the more refined ones up to 1-micron
  • Robotic arms are reliable as they eliminate the large error margin involved in human error
  • The arms have a load capacity within which they can operate and handle heavy payloads