Tham khảo tài liệu 'advances in haptics part 6', kỹ thuật - công nghệ, cơ khí - chế tạo máy phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả | A Haptically Enhanced Operational Concept for a Hydraulic Excavator 217 Intuitive Operational Concept The test operators started with performing a typical working task using the standard joysticks. After this run they performed the same tasks using the new concept. The time to complete a working cycle and the operating errors were compared. An operating error is a motion of the excavator s TCP into the wrong direction due to a wrong operator input. These errors were easily seen due to the predefined task. Reasons for errors are confusions of operating elements or joystick axes. The typical working cycle consisted of loading the bucket with soil rotating the cabin about 90o and lifting the bucket over an obstacle unloading the soil moving back to the initial position and starting the next cycle. Before starting the test operators got a brief instruction to the hydraulic excavator and the operational concepts. Since some learning effects can be observed already after a short time only the first two cycles of each operator were analyzed. It was assumed that short cycle times and less operating errors are indicators for an intuitive operational concept. A paired t-test was calculated for the cycle times t 11 p and for the operating errors t 11 p . The results in Fig. 19 show significant differences between both operational concepts. The cycle time and especially the number of errors are significantly lower. These results coincide with related studies by Wallersteiner et al. 1993 and Lawrence et al. 1990 . The survey showed that the inexperienced operators subjectively benchmark the coordinated control concept better than the standard control concept regarding usability and training time. operational concept operational concept a Cycle time Fig. 19. Evaluation of the proposed operational concept operational concept operational concept b Operating errors Haptically Enhanced Driver Assistance Systems Fig. 20 illustrates the implemented .
