Investigating The Use Of Stereolithography To Build Adaptive Robots

In nature, species have evolved to best suit their niches. Monkeys have evolved to have long arms and dextrous hands that enable them to climb trees and pick fruit. Lions, on the other hand, have evolved to be strong and fast so as to most effectively catch prey in the open savannah. Each species has therefore evolved in order to best cope with typical tasks that are encountered. This can be thought of as optimising to a narrow range of tasks. Human beings have the ability to live almost anywhere. Even early man was found in nearly all climates and surroundings. He is not the strongest, nor fastest, and he is not especially good at climbing trees either. What he has is the ability to think. Moreover, the ability to use tools to transform his body into what is needed for the environment. Weapons for hunting allow him to exceed the lion’s power, and clothing can keep him warm in otherwise inhospitable climates. Therefore he has a very wide range of skills, though none are of great magnitude.

When designing a robot, it is the task of the designer to optimise the robot for the tasks it is likely to encounter, thus maximising the likelihood of success. This however is only good when you are sure of what the robot is going to encounter and the nature of its environment. In the movie ‘Terminator’, the robot played by Schwarzenegger was both strong and tough, thus optimised to kill! In ‘Terminator 2’ however, the new robot on the scene was not as strong but instead had the ability to transform its shape to best suit its environment and thus escape from unpredicted circumstances.

The ability of current robots to modify their behaviour is currently limited by their predetermined structure. In this paper, a robot structure is proposed that has not been optimised to any one task, but that can potentially fulfil a whole range of tasks. It is hypothesized that a more flexible structure allows the robot to better adapt in two ways:

• Increasing degrees of freedom.
• Spreading the risk of failure when the robot is damaged or situated in new environments, by allowing each part of the structure to function in different ways.