Modern diesel engines tend to employ up to 50-70% exhaust gas recirculation (EGR) together with high intake pressure and injection strategies to enable low temperature combustion (LTC) cycles for reducing NOx and soot emissions simultaneously. Obviously, the combustion conditions and exhaust emissions are sensitive at such high EGR rate. And any slight fluctuation in the EGR quantity will bring unintended deviations from the desired engine performance, thus LTC mode is only limited at partial engine operation points. So the engine has to switch combustion mode frequently between compression ignition (CI) and LTC region within a few engine cycles in real application, which may result in combustion cyclic variations and even misfire, especially during transient operation. In order to investigate effect of heavy EGR transient process on engine combustion cycles, the experimental work was carried out on a four-cylinder VM common-rail turbocharged diesel engine. The results show that the oxygen concentration in the intake charge almost maintains at steady level at EGR steady conditions, while the exhaust oxygen concentration is affected by exhaust values opening/exhaust values closing (EVO/EVC), and result in intra-cycle fluctuation, which will approximately bring 2% calculation error bandwidth for EGR ratio. From 37% to 55% EGR ratio, the EGR gas is mainly driven by the pressure ratio of intake and exhaust duct, and it will experience a long accumulating process to reach a new equilibrium. And the inordinate delayed injection timing will promote in-cylinder cycle-to-cycle variation and even misfire, especially during transition from CI to LTC region.

The main structure of the multifunctional loading and unloading machine is analyzed and designed, including feeding conveyor, intermediate conveyor and unloading conveyor. According to the action of each part of the hydraulic system and electrical system design, in order to meet the needs of more working conditions, the working mechanism realized the overall slip, telescopic conveyor lifting, rotating, telescopic; Combined with the convenience of worker operation, three control modes of remote control, workbench control and terminal control are designed.

People’s daily life activities, such as eating, washing and dressing, are very important to the quality of life. However, for many people with disabilities, including those with upper limbs, these tasks prove to be challenging without the help of human caregivers. However, the shortage of medical workers and rising medical costs have created an urgent need for innovation, making aid more affordable and effective. A typical auxiliary task is dietary assistance, which is the basic daily necessities for maintaining health. People with upper limbs and limbs often have difficulty supporting themselves. Technical intervention can solve the problem by bridging the gap between physical ability and necessary functional ability. This design is based on a single-chip microcomputer control system-assisted feeding manipulator design, which can assist in completing the feeding function, and can also add voice or facial recognition modules to enhance the human-computer interaction experience. The design is mainly composed of editing controller-control and detection-power element. That is, the food is fed through a control program, transmitted to a target position through a power element, and whether feeding is completed is judged through a control and detection device. And we will try to add some functional modules to enhance the human-computer interaction experience.