Download FESTA Handbook Version 5 - FOT-Net

FESTA Handbook
Guidelines for FOT Databases and Analysis Tools
7.4.1 Size and weight
The system should preferably have negligible effect on the driver’s use of the vehicle –
including limitations in trunk space.
7.4.2 Connectors and interfaces
State-of-the-art FOTs state that from experience as much as 80 % of the DAS hardware
problems can be deduced to physical connector issues (to the DAS and to peripherals). It is
recommended that connectors with some locking between connector genders are used.
Cable pull-relief should be used when possible.
7.4.3 DAS mechanical cover and ease of access
It is recommended that a layman without tools is able to find and have visual access to any
indicator LEDs on the DAS. Also, having the possibility to connect interface devices without
having to remove covers is preferable.
7.4.4 Crashworthiness and vibration resistance
For all FOTs the minimum requirement for ruggedness is that the entire system should
operate under the normal driving conditions for the specific FOT. including the harsher
situations of normal driving.
7.4.5 DAS environmental requirements
Environmental requirements for the DAS mainly concerns temperature. If the DAS is placed
in a shielded location, the need for water resistance may be negligible, although the DAS
internal parts should be able to withstand reasonable levels of condensation. If applicable, it
is recommended that a simple dust/particle filter is placed by the main air intake of the DAS.
Important considerations include sufficient cooling of the system due to internal heat
generation and for ambient temperature. The cooling needed depends on the processor
used and the workload. If the FOT is using video compression done in software, the need for
processing power may be drastically higher than if only simple signals are recorded. High
processor load generates significant levels of heat. The need for forced ventilation is
depending on the DAS mounting position.
Too high and too low temperatures (both static and transient) do affect the DAS.
Components with moving parts need special attention. Hard drives are some of the most
sensitive components. Automotive grade hard drives are available, although somewhat
more expensive than normal consumer hard drives, and with limited storage capacity. Flash
memory cards or solid state drives (SSD) are available in increasing capacities and are clear
alternatives for operating system hard drives and for storage in lower data volume FOTs.
7.5 Electrical requirements
7.5.1 Power management
The main requirement for the DAS setup is that the installation should never affect or impair
normal vehicle function. This requirement should be enforced in all environmental conditions
and is one of the most critical issues for drivers to accept equipment to be installed in the
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