Motion Capturing

Ergonomics in commercial vehicles

The target of the application is to combine available tools for the motion/movement representation of human models to form an integrated generic solution. This solution will be used to carry out ergonomic validations in a virtual environment as early as the concept development stage.

Premises

  • Recording of various scenes
  • Separation into individual sequences
  • Parametrisation
  • Creation of a library
  • Composition of the individual sequences to form one flow scene
  • Implementation in the VR world to create one integrated flow scene
  • Reliable statements as early as during the concept stage
Life in commercial vehicles:
©Daimler 2013
Stechow/Daimler

In an initial step, motion sequences are recorded using a conventional tracking system.

MoCap systems in ergonomics applications

These sequences are prepared for subsequent processing and segmented into logical and manageable sub-units. In a pool of basic movements, the sub-units are archived using Capture Data Management (CDM).  

A motion configurator is used to put these sequences together to create new synthetic motion flows and to adapt them (simulation). This involves consideration of the intended scenario, the anthropometric characteristic values of the percentiles and the function-relevant geometry of the examination environment. A flow scene created in this way is played into a VR vehicle environment and linked with its environment so that the movements are shown in a congruent manner that is close to reality. The possible movement space is restricted by a specified movement path and by a collision detection feature.

Target of the sub-project “Truck ergonomics simulation”: Creating and assessing realistic motion sequences in VR oneself

During the final stage, a pool contains a sufficient number of motion sequences. This ensures that sufficiently realistic human motion sequences can be created from the memory for certain ergonomics examinations, without the need to re-track any motion sequences.

Example of a scene of climbing into a truck cab

The mere succession of motion sequences appears disjointed and implausible. The differences in posture between the successive takes must be aligned to each other. This is done either by

  • creating defined transition points (posture at the end of taken = posture at the beginning of taken+1) or
  • creating a fade-over effect between the takes, which will make sure that the posture differences are plausible (e.g. a morphing effect of the posture at the end of taken and the posture at the beginning of taken+1) or
  • additionally inserted standard intermediate postures

MoCap acts as an “interpreter” between reality and VR

Cost-effective tracking systems

The focus of the application “Cost-effective tracking systems for validating manual work processes” is on researching and implementing an integrated solution for manufacturability and assembly validation in virtual-only as well as mixed-reality environments.

Mobile system set-up for interactive assembly validation with a fluent passage between the virtual world and reality

Premises:

  • Area of application: manufacturability and assembly validation workshops
  • Interaction of participants with a virtual scene in real time
  • Existing physical components or mock-ups must be usable in the mixed-reality environment. The increasing maturity level during the development stage is linked to the increasing availability of physical mock-ups or parts:

  1. Early manufacturability examinations: exclusively virtual scene
  2. Subsequent process confirmations: mixed-reality set-up with integration of physical components

  • Easy configuration for users
  • Service-based implementation on the basis of the ARVIDA reference architecture
Representation of the three application cases via the process stages of the production planning

The above graphic shows three examples of application cases with typical interaction and visualisation configurations. The workshop leader is free to combine the available technologies in accordance with the examination requirements. Therefore, the interoperability of the services and resources is an essential part of the developed solution and the reference architecture. Based on the reference architecture, information from different sensor sources is recorded, processed and merged so that a complete coordinates graph can be created.

Representation of the employed tracking technologies, software modules and visualisation components

As a result, different and sometimes conflicting manufacturability and assembly targets can be validated simultaneously. For example, the user has the option of validating several manufacturability criteria, such as the accessibility of the screwdrivers and the worker's body posture, at the same time. Furthermore, a higher level of virtualisation ensures that real prototypes are only required during a later stage of the development process. In this way, a high level of potential savings can be achieved and the validation targets can be achieved earlier.