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fuzzy output ponents. It was then necessary to take the maximum of these values as the fuzzy value for each ponent. Finally, these fuzzy output values were defuzzified using the maxproduct technique and the result was used to update each of the motor speeds. (a) (b) (c) Fig. 2. The membership functions used for (a) distance, (b) translation speed, and (c) rotational speed. These functions were adapted from similar work done in reference 3. 4. RESULTS The fuzzy control scheme allowed for the robot to quickly respond to obstacles it could detect in its environment. This allowed it to follow walls and bend around corners decently without hitting any obstacles. However, since the IR sensors39。 measurements depended on the geometry of surrounding objects, there were times when the robot could not detect obstacles. For example, when the IR beam hit a surface with oblique incidence, it would reflect away from the sensor and not register as an object. In addition, the limited number of rules used may have limited the dynamics of the robot39。s responses. Some articles suggest as many as forty rules6 should be used, while others tend to present between ten and twenty. Since this project did not explore plex kinematics or putational simulations of the robot, it is difficult to determine exactly how many rules should be used. However, for the purposes of testing fuzzy logic as a navigational aide, the eight rules were sufficient. Despite the many problems that IR and similar ultrasonic sensors have with reliably obtaining distances, the robustness of fuzzy logic was frequently able to prevent the robot from running into obstacles. 5. CONCLUSION There are several easy improvements that could be made to future iterations of this project in order to improve the robot39。s performance. The most dramatic would be to implement the IR or ultrasonic sensors on a servo so that they could each scan a full 180 degrees. However, this type of overhaul may undermine some of fuzzy logic39。s helpful simplicity. Another helpful tactic would be to use a few types of sensors so that data could be taken at multiple ranges. The IR sensors used in this experiment had a minimum distance of 10 cm, so anything in front of this could not be reliably detected. Similarly, the sensors had a maximum distance of 80 cm so it was difficult to react to objects far away. Ultrasonic sensors do offer significantly increased ranges at a slightly increased cost and response time. Lastly, defining more membership functions