IELTS Reading Breakdown: Insects and Inspired Artificial Robots

For over 2,000 years, humankind has been fascinated by the creation of artificial devices that mimic living organisms. The reading passage Insects and Inspired Artificial Robots guides learners through the evolutionary journey of biorobotics—from the mechanical machines of Ancient Greece and the electromechanical “tortoises” of the 20th century to modern generations of RiSE wall-climbing robots and robotic fruit flies. Analyzing the structure of this passage helps you master the skills of underlining keywords, cross-checking synonyms, and conquering three core question types: Matching Headings, Matching Features (People), and Short-answer Questions.

Reading Passage

Paragraph A

The creation of artificial devices with life-like characteristics has been pursued for over 2,000 years, beginning, as did so many things in our modern world, in Ancient Greece. For example, among the inventions of Hero of Alexandria were a windmill-operated pipe organ and a mechanical theatrical play.

Paragraph B

With the rise of cybernetic approaches in the late 1940s and early 1950s, a wide variety of electromechanical machines designed to mimic biological processes and systems were constructed. Perhaps the best-known and most directly relevant to biorobotics is W. Gray Walters’ robotic “tortoises” Elsie and Elmer. Walters was a physiologist who made important early contributions to electroencephalography and clinical neurophysiology. His tortoises were small mobile robots covered by a hard shell. The robots were driven by steerable motorized wheels and possessed a headlight, a light sensor, and a touch sensor that responded when the shell was hit. Their behavior was controlled by electronic circuit analogues of neural circuits. The behavioral repertoire of the tortoises included exploration, phototropism (both positive and negative), and obstacle avoidance. The activation of these different behaviors in interaction with the robots’ environment could produce a variety of behavioral sequences. Although originally designed to explore Walters’ theories of brain function, the tortoises became objects of popular fascination, much like ancient automata.

Paragraph C

The seeds of the modern renaissance of biorobotics were sown from the mid-1980s to mid-1990s. A key event in this resurgence was Rodney Brooks’ work on behavior-based robots. Although not as directly based on biology as later work, Brooks argued that nontrivial and flexible behavior in a robot could be generated by the interaction between simple control machinery and its environment, demonstrating his point with robots accomplishing tasks such as insect-like walking. Another milestone was Raibert’s work on hopping and legged robots, which emphasized the central role of energetics in the dynamic balance and locomotion of animals. Based on studies of serpentine motion, Hirose developed a number of snake-like locomotors and manipulators. In the early 1990s, Beer, Quinn, Chiel & Ritzmann developed a series of hexapod robots based directly on cockroach and stick insect body morphology and neural control. Early biorobotic work on the sensory side includes Franceshini’s robotic compound eye, Webb’s robotic model of cricket phonotaxis, and Grasso et al.’s robotic model of lobster chemical orientation strategies. An early example of robots whose control was based on theories of human brain function is given by the work of Edelman et al.

Paragraph D

There has been an explosion of work in biorobotics in recent years, with robotic vocal tracts, jaws, retinas, expressive faces, hands, arms, legs, etc. deployed on robotic worms, snakes, ants, flies, crickets, cockroaches, walking stick insects, dinosaurs, bats, lobsters, tuna, pickerel, turkeys, apes, and humanoids. Thus, no brief survey could possibly do justice to the range of work being undertaken.

Paragraph E

A recent example of biologically-inspired robotics is Spenko et al.’s work on a hexapedal robotic climber called RiSE. To grip a vertical surface, this robot combines both bonding mechanisms inspired by the structure of gecko feet and interlocking mechanisms inspired by the structure of insect spines and claws. Additionally, its design follows principles common to many climbing animals:

• A sprawled posture keeps the body close to the surface to reduce the pitch-back moment.

• Front limbs pull inward, and rear limbs push outward to counteract the pitch-back moment.

• A long body reduces the pull-in force required of the front limbs.

• Lateral forces act inward toward the central axis of the body.

• Compliant legs, ankles, and toes help distribute contact forces.

Each of RiSE’s six legs has two degrees of freedom, and the robot also possesses a static tail that presses against the surface to reduce the pull-in forces required of the front legs. The robot uses a wave gait, where only one leg at a time is lifted from the surface. In addition to an open-loop gait generator, RiSE uses a variety of feedback controllers, including: Traction force control, Normal force control, and Gait regulation. RiSE also has a pawing behavior, allowing a foot that fails to grasp on initial contact to reestablish a grip on the climbing surface. Spenko et al. have demonstrated that RiSE can traverse a variety of horizontal and vertical surfaces, including climbing trees and brick or cinder block walls.

Paragraph F

A powerful example of biorobotic modeling is provided by the aerodynamics of insect flight. Traditional aerodynamic analyses, like those used for aircraft, work well for larger animals but fail to explain lift generation in small flying insects due to their tiny wingspans, slow flight speeds, and extremely fast wing movements. However, a recent biorobotic model by Dickinson and colleagues has shed light on insect flight aerodynamics. Due to the delicate size and high speed of insect wings, directly measuring forces is extremely difficult. To overcome this, a robotic model with a 60 cm wingspan was used, submerged in mineral oil to replicate the Reynolds number relevant to small insects. This model identified three major mechanisms for lift generation:

• Leading-edge vortices produce lift during most of the power stroke.

• Rapid wing rotation at the beginning and end of each stroke generates additional lift.

• Wake capture occurs when the wings collide with swirling air left by the previous stroke, producing further lift.

Due to the sensitivity of these mechanisms to wing rotation timing, the model suggests that precise wing motion control is key to steering flight.

Questions 1-6

Choose the most suitable headings for paragraphs A-F from the list below. Write the appropriate number (i-x) in boxes 1-6 on your answer sheet.

List of Headings:

i. A biorobotic model exploring insect flight
ii. Modern practices of artificial device usage
iii. Robotic climber better than gecko
iv. Insect flight inspires the applications of steering operation
v. Prosperity of biorobot family
vi. The revival of modern biorobotics
vii. Combine machines and environment
viii. The advent of robots and their effects on modern society
ix. The most famous biorobot in early days
x. Bionics device is not a modern conception

1. Paragraph A → _____

2. Paragraph B → _____

3. Paragraph C → _____

4. Paragraph D → _____

5. Paragraph E → _____

6. Paragraph F → _____

Questions 7-13

Match the people (A-E) with opinions or deeds (7-11)

7. _________ made contributions to neurophysiology.

8. _________ endowed robots with agility from machinery-environment fit.

9. _________ generated mechanical intelligence inspired by human brain function.

10. _________ modified mechanical models based on insect structure.

11. _________ found the mechanism of insect flight.

Choose words from the passage to answer questions 12-13 (NO MORE THAN THREE WORDS).

12. What plays the most critical role in Raibert’s hopping and legged robots?

13. What allowed direct measurement of the lifting forces of the biorobotic model?

Complete Translation of the Reading Passage

[Paragraph A] The creation of artificial devices with life-like characteristics has been pursued for over 2,000 years, beginning, much like many things in our modern world, in Ancient Greece. For example, among the inventions of Hero of Alexandria were a windmill-operated pipe organ and a mechanical theatrical play.

[Paragraph B] With the rise of cybernetic approaches in the late 1940s and early 1950s, a wide variety of electromechanical machines designed to mimic biological processes and systems were constructed. Perhaps the best-known and most directly relevant to biorobotics are W. Gray Walter’s robotic “tortoises,” Elsie and Elmer. Walters was a physiologist who made important early contributions to electroencephalography and clinical neurophysiology. His tortoises were small mobile robots covered by a hard shell. These robots were driven by steerable motorized wheels and featured a headlight, a light sensor, and a touch sensor that responded when the shell was struck. Their behavior was controlled by electronic circuit analogues of neural circuits. The behavioral repertoire of the tortoises included exploration, phototropism (both positive and negative), and obstacle avoidance. The activation of these different behaviors in interaction with the robots’ environment could produce a variety of behavioral sequences. Although originally designed to test Walters’ theories of brain function, the tortoises became objects of popular fascination, much like ancient automata.

[Paragraph C] The seeds for the modern renaissance of biorobotics were sown from the mid-1980s to the mid-1990s. A key event in this resurgence was Rodney Brooks’ work on behavior-based robots. Although not as directly based on biology as later work, Brooks argued that nontrivial and flexible behavior in a robot could be generated by the interaction between simple control machinery and its environment, demonstrating his point with robots accomplishing tasks such as insect-like walking. Another milestone was Raibert’s work on hopping and legged robots, which emphasized the central role of energetics in the dynamic balance and locomotion of animals. Based on studies of serpentine motion, Hirose developed a number of snake-like locomotors and manipulators. In the early 1990s, Beer, Quinn, Chiel & Ritzmann developed a series of hexapod robots based directly on the body morphology and neural control of cockroaches and stick insects. Early biorobotic work on the sensory side includes Franceshini’s robotic compound eye, Webb’s robotic model of cricket phonotaxis, and Grasso et al.’s robotic model of lobster chemical orientation strategies. An early example of robots whose control was based on theories of human brain function is found in the work of Edelman et al.

[Paragraph D] There has been an explosion of work in biorobotics in recent years, with robotic vocal tracts, jaws, retinas, expressive faces, hands, arms, legs, and so on, deployed on robotic worms, snakes, ants, flies, crickets, cockroaches, walking stick insects, dinosaurs, bats, lobsters, tuna, pickerel, turkeys, apes, and humanoids. Consequently, no brief survey could possibly do justice to the sheer range of work being undertaken.

[Paragraph E] A recent example of biologically-inspired robotics is Spenko et al.’s work on a hexapedal robotic climber called RiSE. To grip a vertical surface, this robot combines both bonding mechanisms inspired by the structure of gecko feet and interlocking mechanisms inspired by the structure of insect spines and claws. Additionally, its design follows principles common to many climbing animals: a sprawled posture keeps the body close to the surface to reduce the pitch-back moment; front limbs pull inward and rear limbs push outward to counteract the pitch-back moment; a long body reduces the pull-in force required of the front limbs; lateral forces act inward toward the central axis of the body; and compliant legs, ankles, and toes help distribute contact forces. Each of RiSE’s six legs has two degrees of freedom, and the robot also features a static tail that presses against the surface to reduce the pull-in forces required of the front legs. The robot uses a wave gait, meaning only one leg at a time is lifted from the surface. In addition to an open-loop gait generator, RiSE uses a variety of feedback controllers, including traction force control, normal force control, and gait regulation. RiSE also has a pawing behavior, allowing a foot that fails to grasp on initial contact to reestablish a grip on the climbing surface. Spenko et al. have demonstrated that RiSE can traverse a variety of horizontal and vertical surfaces, including climbing trees and brick or cinder block walls.

[Paragraph F] A powerful example of biorobotic modeling is provided by the aerodynamics of insect flight. Traditional aerodynamic analyses, like those used for aircraft, work well for larger animals but fail to explain lift generation in small flying insects due to their tiny wingspans, slow flight speeds, and extremely fast wing movements. However, a recent biorobotic model by Dickinson and colleagues has shed light on insect flight aerodynamics. Due to the delicate size and high speed of insect wings, directly measuring forces is extremely difficult. To overcome this, a robotic model with a 60 cm wingspan was used, submerged in mineral oil to replicate the Reynolds number relevant to small insects. This model identified three major mechanisms for lift generation: leading-edge vortices produce lift during most of the power stroke; rapid wing rotation at the beginning and end of each stroke generates additional lift; and wake capture occurs when the wings collide with swirling air left by the previous stroke, producing further lift. Due to the sensitivity of these mechanisms to wing rotation timing, the model suggests that precise wing motion control is the key to steering flight.

Academic Vocabulary Summary

• Artificial devices (n): Artificial equipment or apparatus.

• Mimic / Emulate (v): To imitate or copy.

• Biorobotics (n): The branch of robotics inspired by biological systems.

• Renaissance / Resurgence (n): A revival or renewed vigorous activity.

• Locomotion (n): Movement or the ability to move from one place to another.

• Morphology (n): The form and structure of organisms.

• Interlocking mechanisms (phrase): Mechanisms that fit or lock together.

• Aerodynamics (n): The study of the properties of moving air and the interaction with solid bodies moving through it.

• Vortices (n – plural of Vortex): Whirling masses of air or fluid.

• Steering flight (phrase): Directing or guiding airborne movement.

Detailed Reading Answer Key

Questions 1-6: Matching Headings

1. Paragraph A: x – Bionics device is not a modern conception

Detailed Explanation: The opening sentence of Paragraph A states: “The creation of artificial devices with life-like characteristics has been pursued for over 2,000 years, beginning… in Ancient Greece.” This directly proves that bionics devices are not a modern concept (not a modern conception).

2. Paragraph B: ix – The most famous biorobot in early days

Detailed Explanation: Paragraph B discusses the late 1940s and early 1950s. The author writes: “Perhaps the best-known and most directly relevant to biorobotics is W. Gray Walters’ robotic “tortoises” Elsie and Elmer.” The phrase “the best-known” matches “the most famous” in heading ix.

3. Paragraph C: vi – The revival of modern biorobotics

Detailed Explanation: The first sentence of Paragraph C contains the core keyword: “The seeds of the modern renaissance of biorobotics were sown…” The word “renaissance” is synonymous with “revival.”

4. Paragraph D: v – Prosperity of biorobot family

Detailed Explanation: Paragraph D describes an “explosion of work in biorobotics” and lists a wide variety of robotic body parts deployed across an extensive list of animals, from worms and snakes to bats, apes, and humanoids. This diversity and scale represent the “prosperity” or thriving growth of the biorobotics family.

5. Paragraph E: vii – Combine machines and environment

Detailed Explanation: It is easy to fall into the trap of choosing heading iii (“Robotic climber better than gecko”) because “gecko” and “climber” appear early in Paragraph E. However, the text never claims this robot is “better than” a real gecko. Instead, the paragraph analyzes in detail how the RiSE robot’s design interacts with vertical environments: sprawled postures, limb forces, compliant legs distributing contact forces, and feedback controllers to grip and move across real-world surfaces (trees, brick walls). This illustrates the combination of machines and their environment.

6. Paragraph F: i – A biorobotic model exploring insect flight

Detailed Explanation: The opening sentence of Paragraph F clearly establishes the topic: “…provided by the aerodynamics of insect flight.” The paragraph then describes a specific biorobotic model (“a recent biorobotic model by Dickinson and colleagues”) with a 60 cm wingspan submerged in mineral oil to study and discover how lift is generated during flight. Heading i is a precise match.

Questions 7-11: Matching Features (People)

List of individuals to check against:

• W. Gray Walters (Paragraph B)

• Rodney Brooks (Paragraph C)

• Raibert (Paragraph C)

• Beer, Quinn, Chiel & Ritzmann (Paragraph C)

• Edelman et al. (Paragraph C)

• Dickinson and colleagues (Paragraph F)

7. [W. Gray Walters] made contributions to neurophysiology.

Detailed Explanation: In Paragraph B, when introducing the creator of the robotic tortoises, the text notes: “Walters was a physiologist who made important early contributions to electroencephalography and clinical neurophysiology.”

8. [Rodney Brooks] endowed robots with agility from machinery-environment fit.

Detailed Explanation: Paragraph C highlights Rodney Brooks’ work on behavior-based robots: “…Brooks argued that nontrivial and flexible behavior in a robot could be generated by the interaction between simple control machinery and its environment…” The phrase “machinery-environment fit” is a paraphrase of “interaction between… machinery and its environment.”

9. [Edelman et al.] generated mechanical intelligence inspired by human brain function.

Detailed Explanation: At the end of Paragraph C, the text states: “An early example of robots whose control was based on theories of human brain function is given by the work of Edelman et al.” “Mechanical intelligence” corresponds to the automated control systems of these robots (“robots whose control…”).

10. [Beer, Quinn, Chiel & Ritzmann] modified mechanical models based on insect structure.

Detailed Explanation: Paragraph C provides the evidence: “…Beer, Quinn, Chiel & Ritzmann developed a series of hexapod robots based directly on cockroach and stick insect body morphology…” “Body morphology” is synonymous with “structure” (the physical structure of insects).

11. [Dickinson and colleagues] found the mechanism of insect flight.

Detailed Explanation: Paragraph F asserts: “However, a recent biorobotic model by Dickinson and colleagues has shed light on insect flight aerodynamics. This model identified three major mechanisms for lift generation…”

Questions 12-13: Short-answer Questions

12. What plays the most critical role in Raibert’s hopping and legged robots?

Answer: energetics

Detailed Explanation: Locating the keyword “Raibert” in Paragraph C: “Another milestone was Raibert’s work on hopping and legged robots, which emphasized the central role of energetics in the dynamic balance and locomotion of animals.” The phrase “most critical role”