With two new inertial sensor families, Bosch addresses the needs of modern car design in various areas of the vehicle. The SMA6xy sensor family facilitates the integration of airbag systems, while the SMI7xy family aims at driver assistance systems and vehicle dynamics applications.
The sensors that control the airbag systems are typically distributed across the vehicle. Some are in or near the airbag control system; others are located in the front or rear section or in the doors for early crash detection. The SMA6xy family takes this into account. There are versions available that are designed for peripheral deployment and for the airbag control unit. They are also designed for forces of up to 120g or 480g, depending on the type.
In addition to the normal x and y channels, these sensors are also available with a z channel for measuring acceleration in the vertical axis. So, whatever the desired orientation of the sensor's installation, there is a version to match. This gives airbag system developers greater design freedom. Compared to previous versions, the new sensors are better protected against microcuts -- extremely brief interruptions in power supply to the sensor as a consequence of an impact. The sensors now tolerate interruptions of up to 10 microseconds.
The implementation for integration in the airbag control unit senses forces of up to 120g in all three axes. To facilitate the requirements of individual car designs, the sensors are available in implementations with one or two axes.
The other series of MEMS sensors Bosch released today are designed for utilization in a broad range of body and ADAS applications -- from ESP to hill-hold systems or rollover detection.
This series measures forces of up to 35g and bears the type designation SMI7xy. The series is also optimized for robust operation in environments with limited space conditions.
Again, this family embraces two categories. The SMI720 and SMI740 are designed for basic applications, while the SMI700 and SMI710 meet higher requirements. Depending on the application, the devices meet safety levels up to ASIL D (the highest).
The SMI700 and SMI710 each contain a yaw rate sensor and a 2-axis acceleration sensor; the axis configuration varies by type. The SMI720 is optimized for rollover detection and contains a yaw rate and an acceleration sensor, each with one axis. The SMI740 features similar characteristics but is optimized for vehicle dynamics control.
— Christoph Hammerschmidt
This story originally appeared on EE Times Europe.