What is Soft Robotics?
Can you imagine robots that are able to stretch, bend, and withstand up to 200 atmospheres of pressure, but are not even made from metals? These robots, known as Soft Robots, are the next big thing in robotics. Join me as I dive into the extraordinary realm of these groundbreaking robots, positioned to revolutionize the current robotics industry as we know it.
Soft robotics is a subfield of regular robotics that specifically uses soft and flexible materials. Traditional robotics use materials such as hard metals and plastics while soft robotics typically use rubber, elastomers, silicone, and other flexible polymers.
These materials are an important asset because they allow the robot to be identical to nature by imitating the characteristics of living organisms. For example, many soft robots that have been made include a soft robotic gripper, allowing it to pick up items similar to a claw.
Another one is a soft robotic fish, meant to imitate the movement and characteristics of a fish swimming in water.
Comparisons between both Soft Robotic and Regular Robotics
Navigation Through Unstructured Environments
- Soft robotics: Soft robots demonstrate up to 50% improvement in traversing unstructured environments such as rubble or rough terrain compared to traditional robots.
- Regular robotics: Traditional robots may experience a higher failure rate (up to 30%) in navigating through similar unstructured environments.
Gentle Manipulation:
- Soft robotics: Soft robotic grippers have been shown to reduce damage to delicate objects by up to 80% compared to traditional rigid grippers.
- Regular robotics: Traditional robotic grippers may cause damage to delicate objects in up to 30% of cases.
These unique characteristics of soft robotics distinguish itself from regular robotics, through its usage of adapting to complex environments, adaptability, collaborative work with humans, and other applications where traditional robots would face limitations.
Materials used in Soft Robotics
Elastomers: Stretchy materials like rubber or silicone.
Hydrogels: Soft, gel-like materials that can hold water.
Shape-memory alloys: Materials that can change shape when heated or cooled.
Soft textiles: Fabrics that can be pneumatically or hydraulically actuated.
Why are they different?
Safety: Their softness makes them safer for interactions with humans and delicate objects.
Adaptability: They can deform and conform to their environment, navigating tight spaces and uneven surfaces.
Versatility: They can mimic natural movements of many animals like a fish in water or an insect crawling
Energy efficiency: Their simpler designs often require less power compared to complex motors and gears.
What are they used for?
Healthcare
Surgical robots are being developed for minimally invasive procedures. These Soft robotic systems have contributed to 30% reduction post-operative complications compared to traditional rigid robotic systems due to their ability to conform to anatomical structures.
Exploration
Underwater soft robots are being developed for navigating reefs and shipwrecks. Soft underwater robots have shown up to 60% better maneuverability in complex underwater environments compared to traditional rigid underwater vehicles.
Manufacturing
Soft robotic grippers are able to handle fragile objects in assembly lines. These grippers have demonstrated up to 80% reduction in product damage compared to traditional rigid grippers.
Personal Assistance
Soft robots are being developed for wearable applications in rehabilitation. Soft wearable robots have shown up to 70% improvement in patient compliance and comfort during rehabilitation exercises compared to rigid exoskeletons.
Transforming Industries and Enhancing Lives
Soft robotics can be used in a variety of fields to help contribute to many problems occurring today. The cohesiveness and attributes that soft robotics have compared to regular robotics provide lots of advantages for specific applications that traditional robotics cannot accomplish.
By seamlessly integrating into various fields, soft robotics not only revolutionize manufacturing processes but also enhance healthcare, exploration, and personal assistance. Through their cohesive design and distinctive attributes, soft robots emerge as a transformative force, poised to reshape industries and improve quality of life.
Making a Soft Robotic Gripper
There are many projects that can be created within soft robotics. Whether it’s a beginner project to a very advanced soft robot that is created within labs, I needed to start with something that was suited best for me, a soft robotic gripper. The soft robotic gripper holds many unique and interesting attributes that I found when researching a project to replicate.
Attributes
Versatility: Soft robotic grippers offer enhanced versatility compared to traditional rigid grippers. They can handle a wider range of materials, including fragile or soft objects, without causing damage. For example:
- Soft grippers have been shown to reduce damage to delicate objects by up to 80% compared to rigid grippers.
- They can grasp a variety of objects with different shapes, sizes, and textures, making them suitable for diverse applications in industries such as manufacturing, logistics, and healthcare.
Lightweight: Soft robotic grippers are often lighter than their rigid counterparts, resulting in several benefits:
- Reduction in energy consumption: Lightweight grippers require less energy to operate, contributing to overall energy efficiency in robotic systems. They can lead to up to 30% reduction in energy consumption compared to rigid grippers.
- Wear reduction on robots: The lighter weight of soft grippers results in less wear and tear on robotic arms and actuators, extending their lifespan by 40% and reduce maintenance costs.
Durability: Soft robotic grippers exhibit remarkable durability due to their construction from flexible and resilient materials such as polymers. Specific points to consider:
- Resistance to impact: Soft grippers have shown the ability to withstand forces up to 3 times greater than rigid grippers when subjected to impact or pressure.
- For example, while a rigid gripper might fail when subjected to 100 pounds of force, a soft gripper could withstand up to 300 pounds of force under similar conditions. This substantial increase in force tolerance highlights the durability and robustness of soft grippers in various industrial and robotic applications.
- Longevity: Soft grippers can maintain their functionality over an extended period, even under challenging operating conditions. They have demonstrated up to 50% longer lifespan compared to traditional rigid grippers in certain industrial applications.
This is just a brief overview of the attributes of what a soft robotic gripper can do, and this is where my replication piece comes in.
There are two ways to make a soft robotic gripper, either you make the mold yourself or you use a 3D mold to make it, and they both use the most important material that allows for the creation of the robot, EcoFlex. Ecoflex is a liquid polymer and when cured over time, makes a rubbery, and flexible item.
The Creation Process
Regarding the 3d mold, I had a problem. When ordering the 3D mold for my soft robotic gripper, it would take 2 weeks until it would come, which was very bad since I couldn’t wait that long. That was when I stumbled upon this DIY (79) DIY Soft Robotic Gripper — YouTube tutorial to make my soft robotic gripper at home! Since this is a DIY project, I would need to make my own “3d Mold” using cardboard as a way to pour my liquid in.
After you pour the Ecoflex into the mold, it is required to wait about an estimate 4 hours for the liquid to cure, or you can put it in an oven for about 15 minutes, which gets the job done faster, however I just let it sit over time.
This part of the mold, is referred to as the “Top Layer” of the robot, and the bottom layer composed of something similar. The bottom layer is made with a paper cutout that is the same shape of the Top Layer in order to match the 3 arms of the robot. Then it is placed in a mold surrounded with hot glue, so that is placed inside of it, to be covered with EcoFlex.
After both the top layer and bottom layer were cured, I removed them from the molds and was left with rubber and flexible materials. I was on the right track; however, I wasn’t done yet. I needed to connect both layers together and this is where Ecoflex comes into play again.
I would lay the bottom layer on the floor, put some Ecoflex on it and then put the top layer above it, connecting both layers together. The Ecoflex would act as a glue binding both pieces together. Once both pieces were combined fully, and I wrapped it with ribbon, the next step was to inflate it, and this is the start where I experienced lots of problems.
Results
Here are the challenges that I experienced:
When I inserted the tube, connected a pump with it, and squeezed it, the soft robot was not really inflating. It was curling a bit but it was not curling all the way to make it grab things.
Here’s what I learned from those challenges:
After many days of constant research and confusion, something struck my eye when looking at the soft robot. One of the arms had a very small opening, and during the moment I wondered if this was the source of the problem, an air leakage.
My thought process during this moment was that if I squeeze my pump, air will go inside the soft gripper but would lose its air due to that small opening, making air being released from it. Once I tested this theory out, I was correct!
After sealing up the small opening in one of the arms, I squeezed the pump to see if it would work and the results that came through, shocked me…. The soft robotic gripper still didn’t inflate.
I even tried to use a giant water bottle as a pump to see if it would work but no, not even. Both the pump and water bottle didn’t even inflate it all the way, but I did get more promising results with the pump so I sticked with that method of inflating.Overall, I learned that, I must make every part of the mold is solidified and closed off completely because if there is even a small little opening, air will seep out of the soft robot.
Here is what I learned after completing the creation
This first trial was a great experience in making my first soft robot. I learned how to use Ecoflex when making soft robotics and understandng the aspect of it. I also learned a great amount from the challenges I faced. Making a soft robot is simple yet takes a lot of precision and work to make sure it is perfect for it to do its desired functions. This trial was a failure, but the project wasn’t over just yet. When I declared this trial a failure, my 3d mold came in, and this is where the fun begins!
The Second Creation Process
Once I got the 3d mold, I immediately conducted my next trials underneath it. Like the same procedure in the DIY version, I poured the Ecoflex into the mold and waited for the top layer to solidify. After it solidified, I made the second layer by pouring some Ecoflex onto a tray and put the top player on top of it, and after waiting an additional 4 hours, the new soft robot was made!
This is what the soft robot looked like after being made. Now, it was the moment of truth, would it work how I wanted it to be, or will it not..?
Results
Here are the challenges that I experienced
I inserted the tube inside the soft robot, connected it to a pump, and the results were shocking… It worked! It was inflating and the arms were curling and could grip some things.. but there was still a problem, only two of the arms were inflating, and there was an uneven distribution of air going inside my soft robot.
Here is what I learned from those challenges
When I inflated the soft robotic gripper, one arm was getting a majority amount of air and after it would inflate, arm opposite to it would also inflate. Since there was unevenness in the robot, I pressed down on the arm that was getting the most air, and the air was being distributed evenly to the other arms. I realized that the reason why one arm was taking up most of the air was due to the internal structure of the arm compared to the other arms, let me explain.
When I made the 2nd soft robot with the arm, each arms internal structure was slightly different from each other's. Some were pretty thick on the inside while the arm that took the most air was slightly hollower on the inside compared to the other arms. When inflating the soft robot, the arm that was inflating first, was getting the most air due to its hollow internal structure. It was more accessible to take in the most pressure when all the air was going inside the soft robot compared to the other arms.
This was a good thing to know in mind while facing this challenge with my new robot. In order to make the air divided evenly into my soft robot, I found out that I would need to apply pressure to the arm that was intaking the most air. In order to do this, I would need to apply an extra layer of Ecoflex onto the arm.
When doing so, the extra layer to Ecoflex applies more weight on that specific arm. The added weight on this arm would tone down the amount of air pressure it would take in when I would pump the air tube, so this is where I tried this out.
After applying another layer of Ecoflex onto the arm and waited for it to solidify, I pumped the soft robot once again and the arm wasn’t taking in that much air from before!
When I pumped the soft robot again, the two arms opposite from each other would inflate and a 3rd arm would start inflating as well but there was still an imbalance. Even though the arm with the most accessibility for air was reduced, it still was taking in air a little bit more compared to the arm opposite with it.
Here is what I learned after completing the creation process
I decided to just end it here with any further troubleshooting with the gripper. Even though I faced a challenge with this soft robotic gripper, it still was great, especially its attributes.
A soft robot has 10x the durability compared to a normal robot so I decided to test this out with mine. I would throw it on a while, try smashing it with my fist, stretching it out, and not even a good dent or scratch on this robot.
I also tested out its gripping capabilities with me holding the gripper and making the arms curl while it holds an object, since the air pressure testing didn’t work out all the way. While gripping many objects, the grip strength on this robot was outstanding. It wouldn’t slip or let go of the object. There was a strong and firm grip on my robot when I picked up things like a Rubix Cube or something heavier like a weight.
Final Results
I have learned a lot during this replication phase of making my own soft robotic gripper at home. Even though my soft robotic grippers didn’t work the way it was intended to, it still came out as a fantastic end result due to the capabilities it has! The soft gripper that worked the best was the second trial with the mold.
I was able to test out it’s durability, stretchiness, and inflation capabilities. I have grown a lot with this experience on making a soft robot for the first time and will make sure not to make the same mistakes I made first. This knowledge and process I went through will help me with future soft robotic projects I intend to make as well.
The Soft Robotic industry is a fascinating area to learn about. Soft robots have a vast majority of applications, ranging from deep sea research, environmental disasters, the medical field, deep space, and so many more applications!
The industry is estimated to hit 3 Billion dollars by 2027! Soft Robotic are still expanding and growing in the world and will eventually make a drastic change in the world's current inventions.
Sources:
What is soft robotics? (oculussj.com)
https://softroboticstoolkit.com/resources-for-educators/soft-gripper
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Some things about me:
I am a 15-year-old student at TKS | The World’s Top Innovation Program for Youth. I’m really passionate about computer science and robotics and the many implementations it can have in the world!
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