A 2013 study showed that small cantilevers made from azobenzene-functionalized liquid-crystalline polymer networks could twist and coil when exposed to light. The result suggested a possible route toward biologically inspired robotic movement, but it was a materials demonstration—not a working robot or a practical muscle replacement. The Royal Society of Chemistry’s 2013 account explicitly described real-world robotic applications as far off.
What the researchers demonstrated
The team made small cantilever structures from azobenzene-functionalized liquid-crystalline polymer networks. In the RSC account, external light drove the structures to twist and coil; changes in the light’s polarity and intensity affected their response, while the material’s internal ordering helped determine the direction of torsion. The aim was to broaden the kinds of movement possible in responsive materials, including out-of-plane motion that could matter for more dexterous movement.
As an Amazon Associate I earn from qualifying purchases.
The work was reported by Jeong Jae Wie, Kyung Min Lee, Matthew L. Smith, Richard A. Vaia and Timothy J. White in “Torsional mechanical responses in azobenzene functionalized liquid crystalline polymer networks,” published in Soft Matter in 2013 (DOI: 10.1039/C3SM51574E). The RSC summary describes the result and its context.
Recommended Free Tools
Why a twisting film matters to robotics
Robots need actuators: components that turn an input into movement. A light-responsive material could, in principle, provide motion without relying on a conventional motor at every joint. The researchers’ result was therefore relevant to soft robotics, where flexible materials and varied movement are of interest, and to the longer-term idea of actuators that mimic some aspects of biological muscle.
#1 Best Overall
- BUILD, CODE & DRIVE YOUR OWN ROBOT CAR: Turn coding, electronics and engineering into a working programmable robot car you can assemble, program and drive; ideal for weekend family projects, STEM classrooms, coding clubs, robotics lessons and maker challenges
- EXPLORE FPV, LINE TRACKING & OBSTACLE AVOIDANCE: Control the robot with the ELEGOO app or IR remote, view live FPV video through the onboard camera, follow black lines, avoid obstacles with the ultrasonic sensor and explore multiple interactive driving modes
- BEGINNER-FRIENDLY BUILD WITH GUIDED WIRING: Keyed XH2.54 connectors help reduce wiring mistakes, while the illustrated tutorial and example programs guide beginners step by step from chassis assembly and module connection to programming and the first successful run
- GO BEYOND ASSEMBLY WITH CREATIVE CODING: Program with Arduino IDE to explore movement, sensors and control logic, then modify example code to create custom routes, reactions and robotics experiments that develop coding, problem-solving and engineering skills
- COMPLETE RECHARGEABLE STEM ROBOTICS KIT: Includes an ELEGOO UNO R3 controller board, ESP32-WROVER-based camera and Wi-Fi module, line-tracking and ultrasonic sensors, motors, IR remote and a 2000 mAh rechargeable lithium-ion battery; recommended for ages 8+ with adult guidance for first-time builders
That connection was a possibility, not a demonstrated capability. The experiment showed light-driven motion in small material structures. It did not show an autonomous robot, a complete robotic muscle system, or a device with the control, force and durability needed for practical use. Robotics expert Gursel Alici described the work as one that “makes a significant contribution towards the realisation of biologically inspired robotic systems,” while also raising the engineering challenge of scaling the structures and producing output comparable to skeletal muscle.
What remained unresolved
The 2013 account said the material was limited to small scales and thin films. It identified several hurdles between that result and a practical robot:
Rank #2
- 35+ Guided Electronics Projects: Progress from LEDs and buttons to RFID access, real-time clocks, motion and distance sensing, environmental monitoring, motor control and interactive displays for STEM learning, coding clubs and maker projects
- More I/O and Memory for Larger Builds: The MEGA 2560 R3 provides 54 digital I/O pins, including 15 PWM outputs, 16 analog inputs, 4 hardware serial ports and 256 KB flash for projects that combine more sensors, controls and displays
- 200+ Components for Prototyping: Includes LCD1602, RC522 RFID, RTC, DHT11, HC-SR501 PIR, ultrasonic and water-level sensors, GY-521, MAX7219, keypad, joystick, rotary encoder, relay, SG90 servo, stepper motor, DC motor, breadboard and more
- Learn, Modify and Create: Follow 35+ guided lessons with example code, then adjust sensor thresholds, timing, display text, motor behavior and control logic to turn structured exercises into access systems, monitors, alarms and interactive projects
- Organized for Repeatable Learning: Pre-soldered modules, a solderless breadboard, storage case and small-parts box reduce setup time and keep sensors, LEDs, ICs, wires and other components easy to find between projects
- Scale: structures demonstrated at small dimensions would need to be made useful at larger scales.
- Mechanical output: the actuators would need to generate output comparable to skeletal muscle for the envisioned applications.
- Motion complexity: a useful robotic system would require more than a basic twisting or coiling response.
- Robustness: the material would need to withstand use at larger scales and in more demanding mechanical conditions.
Matthew L. Smith, identified in the RSC account as an assistant professor at Hope College, described the then-current constraint this way: “limitation of these materials, right now, is [that] they are confined to small scales”. The article discussed future research plans; it does not establish that these particular challenges were subsequently solved.
How to read the “flexible future” claim
The title points to a research direction, not a current product category. The study is an example of a material that responds to light with a mechanically useful change in shape. Its significance lies in demonstrating a type of motion that might inform future biomimetic actuators; its limitations lie in the gap between a small responsive cantilever and a robust, controllable robotic system.
Rank #3
- 🎁Ideal Gift for Kids & Teens: Celebrate child’s growing skills and important milestones with this 5-in-1 Programmable robot set. Whether for birthdays, holidays, or achievements, it’s the perfect gift that encourages learning and hands-on fun—a gift that grows with them
- ✨STEM Educational Toys: The robot set for kids ages 8+ combines the fun of STEM learning. It encourages hands-on learning and early programming as they build, which can spark creativity and imagination and provide hours of screen-free play
- 📱Flexible Dual Control Modes: Control the Robotic kit with the intuitive app (Bluetooth) or remote. Enjoy fun features like basic programming, path, and precise movement, exploring endless interactive play
- 🔄 5-in-1 Buildable with Varying Difficulty: The Robot Kit with Progressive Difficulty! From simple robots to complex models, kids can build a robot, dinosaur, car, tank, and more. Adjustable head, arms, and tail allow for fun, playful poses. Perfect for kids 8-12 to develop skills step by step and ignite creativity
- 🛠️Clear & Detailed Build Instructions: This robot kit includes 488 pieces, with clear, colorful step-by-step instructions to make assembly easy. Kids can build their own robots independently or with family, enjoying quality time together and a confidence-boosting building experience
The RSC summary supplies no comparative measurements for force, scale, durability or readiness against other actuator technologies, and it reports no quantitative performance figure. It therefore supports a cautious conclusion: light-responsive polymer networks offered an intriguing way to produce twisting motion, but the 2013 work did not show that they were ready to power practical robots.
Quick Recap
Best Value
- Build your own awesome, wearable mechanical hand that you operate with your own fingers.
- No motors, no batteries — just the power of air pressure, water, and your own hands!
- Hydraulic pistons enable the mechanical fingers to open and close and grip objects with enough force to lift them. Every finger joint can be adjusted to different angles for precision movement.
- Three configurations: right hand, left hand, and claw-like; adjustable to fit virtually any human hand.
- Learn how pneumatic and hydraulic systems are used in industrial robots such as automobile components..2021 The Toy Association's STEAM Toy Of The Year Winner
Rank #4
- 🎁 Ideal Gift for Kids & Teens: This STEM solar robot kit celebrates child’s growing skills and important milestones. Whether for birthdays, holidays, it’s the perfect gift that grows with them and offers screen-free fun
- 📚 STEM Educational Toy: This solar educational toy brings science to life! The fun DIY building experience sparks children's curiosity in engineering and renewable energy, while nurturing their problem-solving skills
- ☀️ Powered by the Sun: Enjoy outdoor play with solar power or switch to a strong artificial light source indoors, such as a flashlight, ensuring uninterrupted play for children. This solar build bot toy encourages kids to have fun while exploring renewable energy
- ⚡ Upgraded Larger Solar Panel: Features a large sun-catching surface to harvest more sunlight and deliver stronger power output. Kids discover renewable energy principles through play - a fun educational toy for ages 8+
- 🤖 12-in-1 Buildable with Increasing Challenge: With 190 parts, kids can build 12 models like robots, cars, and more. From simple beginners to advanced builds, the varying difficulty levels allow it to grow with your child’s skills. Each robot sparks children’s creativity
Product prices and availability are accurate as of the date/time indicated and are subject to change. Any price and availability information displayed on Amazon at the time of purchase will apply.
