8. Soft robotics¶
Introduction¶
Soft robotics focuses on designing robots with materials that are flexible and adaptive, such as silicone, rubber, or fabrics. Unlike traditional rigid robots, soft robots are inspired by living organisms and offer a higher degree of adaptability. This makes them particularly effective for applications in healthcare, wearable technology, and rescue operations where conventional robots might face challenges.
How They Work¶
Soft robots often imitate biological structures by using specialized actuators like pneumatic or hydraulic systems, shape-memory alloys, or electroactive polymers. These mechanisms enable movement and flexibility, allowing soft robots to handle delicate objects, navigate tight spaces, or safely interact with humans.
Design, fabrication and control of soft robots¶
Daniela Rus and Michael T. Tolley Source
Key Components of Soft Robotics¶
1. Flexible Materials¶
Elastomers, Silicone, and Rubber: Known for their stretchability and durability, these materials form the core of many soft robotic designs. Textiles: Stretchable or responsive fabrics are essential for wearable or fabric-based robots.
2. Actuators¶
Actuators enable movement by reacting to external inputs: -Pneumatic and Hydraulic Actuators: Rely on air or fluid pressure for motion, ideal for precise or powerful applications.
-Shape Memory Alloys (SMA): Metals that reshape themselves when heated.
-Electroactive Polymers (EAP): Polymers that flex or contract under electrical currents.
3. Molds and Tools¶
Creating parts for soft robots involves molding. Silicone and other materials are often shaped using molds, which can be 3D printed or manually crafted.
4. Sensors¶
Soft robots often include sensors to detect touch, pressure, or proximity. Conductive or stretchable materials are frequently used to develop these.
5. Control Systems and Power Sources¶
-Microcontrollers: Devices like Arduino or Raspberry Pi manage actuators and sensors.
-Programming: Languages such as Python or Arduino IDE are used to code their operations.
-Power Supply: Batteries or external sources provide the necessary energy for actuators and sensors.
6. Pumps and Compressors¶
For pneumatic or hydraulic systems, pumps are required to control airflow or liquid movement within the robot.
Inspiration from Soft Robotics Applications¶
Exploring soft robotics reveals how inflatables and other dynamic materials can transform structures.
Notable inspirations include:
Pola Demaniuk:¶
This work explores the kinetic potential of pneumatic actuators applied to garments. Based on soft-robotic principles, the clothing embedded with the wearable structures acquires a property of self-assembly on the body, without or with its minimal intervention. The design development investigates how to relate body and fabric form to the movement performed by the robotic actuators made of laminated woven fabrics.
Saskia Helinska:¶
Known for her Unflatables project, she demonstrates how inflatables redefine design boundaries.
Additionally, advancements like sensor-equipped textiles developed at MIT showcase the potential of integrating robotics with wearables for medical and athletic training.
Soft-Actuated Can Gripper Robot¶
Introduction¶
This project showcases a compact robotic gripper designed to interact with small cylindrical objects, such as cans or bottles. The gripper is driven by a micro servo motor and uses 3D-printed gears and soft components to mimic a pinching motion, allowing it to gently yet securely hold objects.
Purpose and Motivation¶
- To explore how soft robotics and actuation mechanisms can be applied in assistive devices or automated systems.
- To create a low-cost, customizable gripper that can be used in vending robots, automated drink dispensers, or even prosthetic tools.
- To experiment with combining rigid and soft structures for better adaptability and functionality.
Materials and Components¶
- Tower Pro SG90 Micro Servo Motor
- 3D-printed gear system and frame PLA
- Arduino Uno
- Jumper wires and breadboard
- Power source, USB
- Hot glue or fasteners
- Bottle
Procedure¶
- Design the Gears and Frame o Create or download 3D models of two interlocking gears and a housing unit to hold the can. o Print the components using a 3D printer.
- Assemble the Gears o Mount the gears into the base structure. o Attach them to the servo horn and opposite axle.
- Mount the Servo Motor o Fix the servo motor inside the housing beneath the gears. o Connect it securely so that the rotation of the servo moves one gear and rotates the other.
- Connect to Arduino o Wire the servo signal pin to a digital PWM pin on the Arduino. o Provide power (5V) and ground connections.
- Upload the Code o Use basic Arduino servo code to control the gear rotation based on angle inputs.
Arduino Code Example¶
#include <Servo.h>
Servo h;
void setup() {
// put your setup code here, to run once:
h.attach(4);
}
void loop() {
// put your main code here, to run repeatedly:
for(int i=100;i<=180;i++){
h.write(i);
delay(5);
}
delay(20000);
for(int i=180;i>=100;i--){
h.write(i);
delay(5);
}
delay(20000);
}
Potential Applications¶
• Automated vending or packaging systems • Prosthetic tools that grip objects with adaptive pressure • Educational demos for gear systems and actuation • Smart kitchen appliances (e.g., auto-serving robots)
Reflections and Next Steps¶
This prototype demonstrates how mechanical movements can be controlled in a soft robotic way, using simple electronics and fabrication. In the future, sensors can be added for feedback, or the gear system can be replaced with more flexible, biomimetic mechanisms.
Results¶
