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In order to achieve the accurate trajectory tracking for a high-speed tracked vehicle in off-road conditions in the case where it is known that the desired trajectory is a large curvature curve, new research directions are being developed. In the framework of the Model Predictive Control (MPC) algorithm, the simplified ideal kinematics model of the tracked vehicle that ignores the sliding steering characteristics is applied to reduce the iterative solution time under high-speed driving conditions. By adjusting the weight coefficients of the objective function, the trajectory tracking accuracy is improved. This research is based on an unmanned electric drive tracked vehicle and carries out simulation experiments. Through real vehicle experiment, the control sequence of the experienced driver under the certain scene is collected, and then the vehicle control experience of human is obtained. Through simulation experiment, the vehicle tracking errors under different MPC weight coefficients of different curvature curves are obtained. In addition, the tracking control sequence is compared with the driver's control data. By the data analysis, the sensitivity of each weight coefficient to the tracking accuracy and how to create a driving mode that is closer to human by adjusting the weighting coefficients are determined.

Objective To establish a metabolic syndrome model of C57BL/6 mice by high-salt and high-fat diet, and investigate the effects of angiotensin converting enzyme 2 (ACE 2) and angiotensin (1-7) on renal damage in mice. Methods Fifty-six male C57BL/6 mice were randomly divided into 7 groups (8 each), and fed with normal diet (0.3% NaCl, 10% fat), high-salt diet (8% NaCl, 10% fat), high-fat diet (0.3% NaCl, 60% fat), high-salt and high-fat diet (8% NaCl, 60% fat), high-salt and high-fat diet with enalapril 20mg/(kg•d), with valsartan 50mg/(kg•d), and with valsartan 50mg/(kg•d) plus Mas receptor antagonist (A-779) 150ng/(kg•d), respectively for 16 weeks. Basal metabolic index including blood pressure, body weight, blood glucose and urinary albumin excretion rate (UAER) were tested. After intraperitoneal anesthesia with chloral hydrate, the blood was collected from the carotid artery. Serum angiotensin Ⅱ and angiotensin (1-7) levels were detected by ELISA; Western blotting was performed to evaluate the expression of ACE 2 protein and collagen Ⅲ in renal tissue; renal pathological changes were observed by HE and Masson staining. Results The blood pressure, ratio of visceral fat weight/body weight, blood lipid, blood glucose and UAER increased significantly in the C57BL/6 mice fed with high-salt and high-fat diet for 16 weeks, and the renal fibrosis change was obvious, serum angiotensin Ⅱ level increased, expressions of ACE 2 and angiotensin (1-7) decreased significantly in the renal tissue. In different intervention groups, valsartan obviously alleviated the abnormal metabolism, ameliorated renal injury, promoted the expression of ACE2 and angiotensin (1-7) in the kidney and serum. However, no significant change was observed in the groups with intervention of enalapril or valsartan+A-779 compared with non-intervention group. Conclusions High-salt and high-fat diet can be used to successfully establish the model of metabolic syndrome in C57BL/6 mice. Valsartan, an angiotensin Ⅱ receptor blocker, can alleviate the metabolic abnormality caused by the high-salt and high-fat diet, and the protection mechanism may be related to up-regulation of angiotensin (1-7). DOI: 10.11855/j.issn.0577-7402.2013.10.001

Hull design of a tracked vehicle plays a critical role in the vehicle mobility, crew protection and combat performance. This work is intended to design a hull of 50 Ton tracked vehicle using conventional layout of suspension and running gear components. Driver compartment of hull is designed based upon driver height of 1.69m. Critical hull parameters such as angle of departure, location of 1st road wheel w.r.t idler wheel, location of last road wheel w.r.t sprocket and distribution of middle road wheels are calculated. Finally, designed hull is modeled in Pro/Engineer software and Recurdyn software is used to ascertain vehicle performance in various prototype tests. In the wake of scarcity of papers on this subject, this paper not only outlines the process of hull design for conventional tracked vehicles but also for unconventional ones such as autonomous tracked vehicles.

This paper presents a new modulation method and a half-bridge power driving of high speed on/off solenoid valve. The low-side driver of solenoid valve has slow dynamic response and cannot satisfy the clutch’s requirements of regulating pressure and reducing power loss. For the sake of solving these problems, a bi-state modulation scheme is proposed and the half-bridge power driving circuit is designed to improve the current step response. The comparison between the low-side driver and the bi-state modulation power driving was examined by experiments. The results indicate that bi-state modulation power driving is fit for modulating the pressure of shifting clutch; the current step response of the solenoid valve performs better. In addition, the over-heating problem of the regulator valve is improved noticeable.

Digital signature with message recovery is regard as a useful method to shorten signature. This paper presents an identity-based signature scheme with message recovery, which applies to the Combined Public Key System. The scheme is provable secure against existential forgery against adaptively chosen message and ID attacks in the random oracle model under the elliptic curve discrete logarithm assumption. The proposed scheme can recover message with arbitrary length and shorten the total length of the original message and the appended signature compared with others. The proposed scheme is especially suitable for the computation and communication source constrained, such as Ad-hoc network.

Based on BF6M1015CP electronic diesel engine (it is a supercharged, water-cooled engine. It has 6 cylinders and it is for heavy-duty vehicle) and HD4070PR electronic automatic transmission (it covers heavy-duty applications requiring high input horsepower and torque. It contains torque converter module, control module, planetary module and output module. It has 7 forward gears and a power-take -off (PTO) and a retarder), the paper analyzes the shift system of an electronic automatic transmission. To improve the shift quality, in the paper the different control methods in different phases are used and reviewed that include the open-loop control, fixed ramp rate, and closed-loop control. According to using CAN bus, itpsilas not only feasible to use CAN network following SAE J1939 standard, but also can meet the requirements of the communication control in the vehicular integrated power-train control system. At last, through a bench test, the control strategy and integrated power-train control system of shifting process of the engine and electronic automatic transmission were obtained. Finally, though a bench test, the control strategy of the electronic automatic transmission was obtained.