A transmission control unit able to be directly mounted on the transmission has been developed for applications ranging from small to medium-sized vehicles.Direct mounting of the unit has reduced the distance between the transmission and the control device, making it possible to reduce the length of the harnesses. In addition, hierarchical design of the control software and sharing of the solenoid driver have made it possible to apply the unit to the control of a variety of transmissions.Vehicle tests and simulations were conducted in order to obtain a detailed understanding of the temperature of the electronic components inside the unit under the conditions it would be exposed to when direct-mounted and implement appropriate responses. As a result, the maximum operating temperature of the unit was increased against conventional body-mounting conditions. The rigidity of the mounting bracket and the connector terminals was also increased, increasing the maximum allowable vibration frequency to 2000 Hz. These measures made it possible to apply the unit to a wide variety of vehicle types, from small to medium-sized.
Article of Honda R&D Technical Review Vol.27 No.2 (37 - 42)