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In order to reduce the movement energy consumption of the hydraulic excavator and realize the reasonable and effective operation of each joint, a joint interpolation method based on a T-type velocity curve is proposed to realize the optimal energy consumption trajectory planning of the hydraulic excavator. In this method, the speed of each joint is set as uniform acceleration, constant velocity, and uniform deceleration to ensure the stability of the hydraulic excavator in the operation process. Under the constraint conditions of the joint angle, angular velocity, and angular acceleration, the improved adaptive genetic algorithm is used to optimize the uniform acceleration (deceleration) and constant velocity motion time of each joint, obtain the optimal motion curve of each joint, and realize the optimal energy consumption trajectory planning of the hydraulic excavator. The interpolation programming method based on the T-type velocity curve is simulated and compared with the interpolation results of the quartic polynomial under the same conditions. The experimental results show that the trajectory planned by this method has low energy consumption, avoids unnecessary movement of each joint, effectively reduces friction loss, and makes the excavator complete the operation smoothly and with low energy consumption.

To satisfy the requirement of the polarized light celestial positioning for the high precise information of solar spatial position, a new detecting method for the position of the sun by a new three channel polarization imaging system is proposed based on atmospheric polarization mode. The method is used to calculate the position of the sun by using the polarization information of the atmospheric polarization mode. Compared with the traditional method based on spot detection, the current one is an indirect calculation method to calculate the sun position by using the polarized light characters. This method has advantages such as wide field of view and high precision. The system consists of industrial CMOS lens, polarizer and fish-eye lens. We build up an experimental platform to verify the method based on theory. The experiment shows that the measurement accuracy is 0.02°. Therefore, this method not only meets the requirement of detection, but also provides a new solution for the field of the sun position detection. [ABSTRACT FROM AUTHOR]

Objective: To investigate the effectiveness of tibial transverse transport (TTT) combined with nose ring drain (NRD) in the treatment of severe diabetic foot ulcer., Methods: The clinical data of 60 patients with severe diabetic foot (Wagner grade 3 or 4) ulcer who were admitted between April 2017 and August 2020 and met the selection criteria were retrospectively analyzed. Among them, 30 cases were treated with TTT combined with NRD (TTT+NRD group), and 30 cases were treated with TTT (TTT group). There was no significant difference in gender, age, diabetes duration, preoperative glycated hemoglobin, comorbidities, wound area, and duration, side, and grade of diabetic foot ( P >0.05). The wound healing time, wound healing rate, amputation rate, recurrence rate, duration of antibiotic therapy, hospital stay, number of hospitalizations, and number of operations were recoreded and compared between the two groups., Results: No obvious surgical complications occurred in the two groups. Patients in both groups were followed up 3-13 months, with an average of 5.7 months. The duration of antibiotic therapy and hospital stay in the TTT+NRD group were significantly shorter than those in the TTT group ( P <0.05). There was no significant difference in wound healing time, wound healing rate, number of hospitalizations, and number of operations between the two groups ( P >0.05). During follow-up, there was no recurrence of ulcer in the TTT+NRD group while 2 recurrent cases (6.7%) in the TTT group. The difference in recurrence rate was not significant ( P =0.492). One case (3.3%) in the TTT+NRD group underwent amputation due to acute lower extremity vascular embolism, and 1 case (3.3%) in the TTT group underwent amputation due to secondary necrosis. The difference in amputation rate was not significant between the two groups ( P =1.000)., Conclusion: TTT combined with NRD is an effective method for the treatment of severe diabetic foot ulcers with deep infections or relatively closed cavities or sinuses. It can shorten the time of antibiotic use and the length of hospitalization; and the NRD has a good drainage effect without obvious comorbidities, procedure and the postoperative care are simple and easy to obtain materials.