Vehicle dynamics

Sherpa Engineering was created in 1997 and ever since we have been involved in vehicle dynamics and suspension system activities with customers like PSA and Renault. We have spread this experience to other transport industries like trucks and submarine engines.

Our success is driven by our deep experience and our specialized libraries and models gathered in our PhiSim tool.

Our offer

We offer relevant models based on the PhiSimVehicleDynamics library that was applied to a large variety of vehicle systems. In addition we propose expert services, training and we can also advice and accompany our customers in their modeling activities.

PhiSimVehicleDynamics library

We have capitalized our experience on this topic on the PhiSim library called PhiSimVehicleDynamics. This library contains vehicle models on 2D and 3D where in addition to the system the driver and the environment (roads, etc) are represented.

PhiSimVehicleDynamics is intended for modeling and simulation of vehicle systems during all development phases:

  • Circuit architecture validation and selection of the most appropriate components
  • Design and validation though simulation with the control system
  • Definition of the functional test plan

PhiSimVehicleDynamics is composed of basic elements related to mechanics and automation domains. By assembling these elements, models are configured in order to reproduce the dynamic behavior of the vehicle. Models exist in 1, 2 or 3 dimensions:

  • 1D : only longitudinal behavior in one direction is considered (X direction)
  • 2D : longitudinal and side behavior are considered (X, Y directions and yaw angle)
  • 3D : 3 degrees of freedom are considered (X, Y, Z, roll, pitch, yaw angle)



Some of our typical studies are:

Organs and subset dimensioning

  • Functional specifications for hydraulic and mechanical organs
  • Tools for dimensioning
  • Organic function dimensioning: braking, power steering, differential…

Modeling and simulation

  • Definition of the most adapted model level
  • Construction of the simulator in different environments (Simulink, AMESim)
  • Functional tests via simulation

Control system design

We have designed control systems at different levels:

  • High level control acting over the global vehicle function. For instance, ABS/ESP braking system: longitudinal and side behavior regulation by calculation of pressure target in each brake caliper.
  • Low level control acting over a given organ. For instance, ABS/ESP braking system: regulation of brake caliper pressure by control of 12 valves and hydraulic pump.
  • System integration and validation activities thanks to tests via simulation or on real vehicle.