For the realization of this project with electric rear doors, we took as a basis the most suitable mechanisms. Namely mechanisms from Mercedes Maybach. There is a similar system in Rolls-Royce, but it is from Maybe it was easily built in place of the standard door stroke limiter. With the help of this mechanism it became possible to realize both opening and closing of doors.
However, it seemed to us not quite interesting to implement the project only for the function of door closing, as it is realized in Maybach and Rolls-Royce, so it was decided to realize automatic closing and opening of doors.
The first step was to determine the logic of operation of the standard locks on Cadillac. They turned out to be electronically controlled, which made our task easier. The second stage was to determine the logic of the drive mechanism itself. The third stage was to develop a theoretical control model.
Having collected all these 3 points in a single whole, we came to the conclusion that it can be realized only programmatically with the use of an intermediate ECU, which will implement control algorithms and the combination of two separate structures – the car and a third-party drive system on the basis of a programmable process and hardware external strapping. Taking into account the operating logic of the car and the drive mechanism, a test ECU was manufactured, which we taught to connect with the car and the door actuator.
Further modernization of this bundle revealed both problems and logical blocks that required software and hardware solutions. Some elements of the control system turned out to be superfluous and were realizable by software. And protection systems, on the contrary, required hardware solutions, this led to the exclusion of many elements from the test system and the addition of more compact solutions.
As a result, the final intermediate ECU turned out to be simpler than expected. The final version implements such things as:
– Protection against door opening when the car is moving
– Protection against moisture ingress into the control keys.
– Possibility to stop the mechanism at any moment of the system operation.
– The mechanism has sufficient torque to operate the doors, but at the same time it will not cause significant damage during its operation both to the body elements and to the accidentally caught objects on the way.
Based on feedback from the customer, we will edit the software!