Description of the problem
Velocity Total is different than Velocity on the vehicle. The question is on how to validate either DS-IMU or the velocity meter in the vehicle have a problem?
Description of the solution
Related to the ticket: https://support.dewesoft.com/a/tickets/125866
You can calculate velocity out of GPS position data. You can use the C++ script. In the attached DXD you will see that the C++ script calculates very compliant velocity as GPS module. So we can conclude that the velocity meter in the vehicle is malfunctioned.
C++ script