Independent development of domestic automatic transmission

The Chinese auto market has achieved world-renowned achievements in just a few years, but the key technologies that affect the competitiveness of automobiles have not been able to break through, especially the automatic transmission technology.

In 2012, China's passenger car production and sales exceeded 15 million, passenger car automatic transmission accounted for about 39%, close to 6 million units, but the independent brand automatic transmission total output of about 35,000 units. It is estimated that in 2017, the passenger car automatic transmission capacity will be 7 million units, of which the self-owned brand automatic transmission will have an annual output of about 500,000 units, accounting for 7% of the total automatic transmission. Obviously, the development of the autonomous automatic transmission and the automotive industry is extremely inconsistent, which has seriously hindered the healthy development of the automotive industry. Since 2005, domestic OEMs have been struggling to find automatic transmission resources. However, in addition to the fact that some powerful OEMs can obtain imported automatic transmission resources, the general OEMs cannot obtain the required resources.

In order to change the status quo of automatic transmissions without cars, a variety of automatic transmission development booms have emerged across the country, and all manufacturers are striving to acquire their own automatic transmission technology and products in this boom, thus emerging in China. The automatic transmission market has a place. However, this road is not smooth, and the difficulty and investment are much higher than their own imagination. In the past ten years, there is still no obvious effect.

Domestic involvement in automatic transmissions began around the 1980s, but the real emphasis and high investment began in 2003. There seems to be no main engine factory that does not involve the development of automatic transmissions. Suppliers with certain strengths are also developing automatic transmissions. Therefore, there are many development projects, but few have progressed smoothly. This cannot but cause us to reflect. After a summary analysis of the development status of some domestic main automatic transmission projects, the author predicts that DCT (Dual Clutch Transmission) will be the mainstream of future automatic transmissions.

1. Independent development of CVT

The project was launched in 2004 and is expected to be completed in three years. It was actually completed in 2012 and took eight years. The development budget is 50 million yuan, and the actual development investment is 200 million yuan.

The main reasons for the significant increase in costs are: the project takes much longer than planned; a lot of work is not planned; the lack of key component development is expected; the quality of parts is not up to standard, long-term rectification and replacement of a large number of suppliers; development difficulty and test verification beyond imagination; TCU (Automatic Transmission Control Unit) control development has not been valued.

The main reason is that the project is not long-term: the lack of understanding of the automatic transmission, including management and project personnel, such as vehicle, engine, supplier, developer and project decision-makers; underestimation of TCU control difficulty and development cycle; neglect reliability, Process and quality development, as well as the corresponding test verification workload; system interface coordination and project management are not smooth.

The products developed by the project are applied to the whole vehicle, and the results of the test drive evaluation are not satisfactory. For the CVT, this result is somewhat disappointing, especially the performance of the medium and high throttle.

2. Commissioned to develop DCT

The project was launched in 2007 and is expected to be completed in four years. It was actually completed in 2013 and took six years. The development budget is 200 million yuan and the actual development cost is 300 million yuan.

The main reasons for the significant increase in costs are: too many changes in the transmission design caused by changes in the entire vehicle and engine; the quality of the parts is not up to standard, and the long-term rectification; the test development and verification workload is twice as much as the original plan; the project takes much longer than expected. The main reasons for the long time-consuming projects are: insufficient understanding of automatic transmissions, including management and project personnel, such as complete vehicles, engines, suppliers, developers and project decision makers; parts quality takes a year and a half to rectify, correspondingly The test verification period is extended; the influence of TCU control on the consistency of shift quality.

3. Joint venture development DCT

The joint venture project was launched in 2011 and is expected to take three years to complete with a budget of 1.3 billion yuan. The advantages of the project: the source of technology is guaranteed, the risk is small; the manufacturing process is mature, the quality is guaranteed; the product planning is good, which helps the project start. Disadvantages: Although the equity of the joint venture parties is equal, the status is not equal, the joint venture relationship is stable; the foreign technology monopoly, the Chinese side has difficulty in having a voice; the investment is large and the cost is high.

4. Independent + commissioned development DCT

The project is in the form of autonomous + commissioned, and the commission is mainly in TCU control and verification consulting. Launched in 2009, it is expected to be completed in four years. The actual cost is five years, the development budget is 100 million yuan, and the actual development cost is 120 million yuan. Advantages of the project: relatively low cost; establishment of development capabilities; easy to coordinate and control. Disadvantages: The definition of interface between software and hardware (ontology) is not clear; software is greatly affected by hardware changes; responsibility is difficult to define.

Through the analysis of the above four cases, the author believes that the form of autonomy + entrustment is the most favorable.

1. Insufficient understanding of the automatic transmission, insufficient attention

In particular, decision-making management often uses engine development logic to consider the development of automatic transmissions. There is nothing wrong with this, but unfortunately the automatic transmission does not yet have the environment and conditions for engine development. For example, engine technology is very mature and widespread. Even if there is continuous technological innovation, its technology has a good inheritance foundation, low risk and difficulty. Therefore, in general, technology maturity and channels are abundant. Moreover, many key technologies of the engine are guaranteed by professional suppliers, such as heat engine design, control system EMS, EFI system, etc.; the engine can be developed relatively independently, and the dependence on the whole vehicle is not high.

Relative to the engine, the automatic transmission technology is highly concentrated in a few OEMs or suppliers, such as AT (Hydraulic Automatic Transmission) with Aisin, ZF, etc., CVT with Giteco, Bonzi, etc.; suppliers do not have automatic transmission Key technologies, especially electronic control technologies, such as TCU control strategies; automatic transmissions cannot be developed independently, closely related to engines, complete vehicles, etc., highly integrated, such as interface and communication management between TCU and EMS, automatic transmission and chassis, suspension Between (affecting shift quality, NVH and drivability, etc.).

Automatic transmission projects rely on human management rather than process; vehicle support for automatic transmissions is not in place, causing projects to be shelved or postponed. Suppliers lack experience in automatic transmission parts and do not understand the application characteristics and operating environment of automatic transmissions. The parts of the automatic transmission still remain at the level of photo processing, and do not understand the application conditions and characteristics of the parts (refer to the manual transmission); lack of development concepts, and no relevant development tools and capabilities, it is difficult to support simultaneous development.

2. Lack of pragmatic cooperation development

(1) Fully self-developed The technical conditions for the development of automatic transmissions in China are still immature, especially in key technologies and system integration. If it is completely autonomous, there may be cases of low development quality, long project cycle and uncontrolled cost; if it is developed independently, some technical barriers are difficult to break through, and the result will sacrifice the performance and quality of the automatic transmission, such as comfort, safety and fuel consumption. At present, there is still no objective data in China that can say "YES" or "NO".

(2) Complete commissioning - turnkey mode Automatic transmission development involves target development, definition, design, system integration, prototype manufacturing, test development, verification, process development, production support, TCU control development and TCU calibration. Most technology companies are only good at designing one, and very few may involve more and deeper, but the process, production and verification are absolutely weak. All in all, it is not wise to develop an automatic transmission by “complete commissioning”.

(3) Buying off-the-shelf technology The off-the-shelf technology that can be purchased is often not the latest (such as AT, CVT, etc.), or even eliminated, so the purchase of technology is not conducive to the product market. The purchase technology involves technical digestion, conversion development (process, verification, etc.) and TCU control redevelopment, calibration, etc., so there is no obvious time advantage, and the cost is high. The introduction of 4AT and 5AT projects in China in the past few years is evidence.

(4) Joint venture An open joint venture will help the development of the enterprise, but a conditional joint venture will soon be a stumbling block to the development of the enterprise. At present, the status of domestic automatic transmissions, joint ventures can only be conditional, so the overall trend is not optimistic, unless individual exceptions, such as the joint venture itself is the relationship between customers and suppliers; the OEM has the ability to digest most of the capacity. Joint ventures are one of the ways to solve the current difficulties of automatic transmissions, but they cannot be completely relied on.

3. Technical threshold is high

(1) Technology patented automatic transmissions are mainly AT, CVT, DCT and AMT (Electronic Control Mechanical Automatic Transmission), with a single structure, easy to be protected by patents, to circumvent patents, only to innovate or purchase, but may be sued or in performance, life There are risks in terms of indicators.

(2) Technical channels AT and CVT are basically monopolized, the channels of acquisition are single, and the manufacturing system is not easy to be compatible. The source of DCT technology is relatively large, and it has certain inheritance with the domestic manual transmission manufacturing base.

(3) Special technology Lack of hydraulic control technology (TCU + hydraulic valve body) or electronic control technology (TCU + electronic control actuator), including the corresponding design, verification and production supply system.

(4) Supplier “zero” basis The supplier is still in its infancy, no technology, no experience, large investment, uncertain returns, and there are no basic conditions for mass production in China, such as quality consistency and cleanliness. Lack of key component suppliers such as starters (clutches, torque converters, etc.), hydraulic valve bodies, etc.

(5) System integrated automatic transmission as the connecting hub of engine, vehicle and driver, the four can only realize automatic shifting by integrating one; to achieve the whole vehicle function or target, the automatic transmission must master the engine's torque and speed. The engine's suspension must be optimized based on the automatic transmission;

In short, automatic transmissions must be developed based on vehicle conditions.

4. Lack of development processes and means

(1) There is a general lack of a design-based database such as the automatic transmission load spectrum based on the same vehicle life; the requirements and specifications of the automatic transmission for the engine and the entire vehicle, including torque, speed fluctuation rate, response time, etc.; Product benchmarking database, shifting comfort, efficiency, fuel consumption, weight, process and cost; automatic transmission subjective and objective evaluation specifications.

(2) Basis and means of verification The essence of the test is to find out in advance the problems that may occur in the actual use of the automatic transmission in the future, so it is not a bad thing to encounter problems in the test. Conversely, if the test item passes, the problem may be masked or over-designed. At present, most enterprises' test specifications are not rigorous, or they are borrowed or referenced, lacking practical research, so they may cover up the problem; the test lacks planning, such as DVP (design verification plan), the actual development process, the test resources are insufficient, and the development cannot be completed as scheduled. The method of test verification is insufficient, such as insufficient bench resources for testing, or insufficient vehicle verification for reliability.

5. Lack of an effective supply chain system

There is a lack of domestic suppliers of key components, and domestic suppliers are unable to participate in simultaneous development, and there are no key parts manufacturing processes and verification specifications.

Objective positioning cooperation mode

International technology development companies are not all-powerful but have expertise. They should foster strengths and avoid weaknesses and cooperate with them. Electronic control is the key to the development of automatic transmissions, directly affecting the performance, compatibility and safety of automatic transmissions. It is recommended to cooperate with technical companies with practical product experience. Test verification is critical to the success of the project. If there is no experience, the experienced partners should select the design verification plan and develop the test specifications.

2. Avoid cost of retreat

A suitable cooperation model can help improve the quality of development, shorten the cycle, and reduce costs. As shown in the figure, in general, test verification is the main cost of development, followed by design and control. According to personal opinion, if the method is reasonable, the cost of new development projects can be saved by more than 30%.

Correct understanding of the current situation of automatic transmission is the necessary process for its development. It is necessary to concentrate on developing an automatic transmission to improve resource utilization. At the same time, establish horizontal alliances and purchase products to reduce investment; joint development, production alone, and sharing of property rights.