Available for passive and active marker systems, this is an inexpensive and vital tool for any lab that performs 3D and force measurements.
The MDT-2 (Mechanical Testing Device) is a precision-machined tool that can be assembled in less than a minute to create a force plate test object suitable for a number of 3D biomechanics laboratory tests. It allows the user to apply a pure force vector to a force plate within the Motion Capture environment and determine the alignment of the force plate within the calibrated 3D measurement space.
The MTD-2 is comprised of the following items supplied in a plastic storage case:
- Five wands
- Five retro reflective markers (for passive systems).
- Five mounting disks (for active marker systems).
- Calibration testing rod with two (3/8-16 NC) threaded conical tips.
- Test plate with dual bearing points.
- Handle with recessed bearing surface
Laboratory calibration tests are conducted in order to ensure the accuracy and reliability of kinematic and kinetic data which are essential to the appropriate application of movement analysis data and research purposes. Thorough laboratory calibration includes the accurate determination of the positions of the force platform(s) and cameras in the laboratory coordinate system, as well as correct setting of force platform parameters such as analog scale factors and origin offsets.
Any errors in the parameter settings or calibration measurements can lead to incorrect values of kinematic and/or kinetic variables calculated during a movement analysis.
The calibration test incorporates data derived from the force platform and data generated from the camera measurement system. The degree of spatial and temporal agreement between these two sets of data provides an assessment of the joint working status of the kinetic and kinematic systems.
A small number of variables are calculated and presented for inspection – these enable the user to detect the presence of errors from a large number of potential sources.
A simple test using the MTD-2 in any gait analysis lab can document relationship of any force plate within any 3D data collection volume. The device is simple to use - just assemble and use it to apply a force to the plate that you wish to test and then analyze the data using the CalTester software package available from C-Motion.
Load cell Support
The MTD-2LC option provides Load Cell support for existing MTD-2 users. This option includes a new central rod and tip for the MTD-2 modified to accept a Futek LCM200 Load Cell. This option does not include the load cell or load cell amplifier and other manufacturers load cells may be substituted if they use a standard US 3/8-24 thread at both ends.
The MTD-2LC option is designed so that the load cell attaches to the bottom of the MTD-2 between the new rod and the new tip. The overall length of the MTD-2 is unchanged with the new rod when used with a Futek LCM200 Load Cell. The modified MTD-2 would be virtually identical in all respects to a standard MTD-2 with virtually the same mass and identical dimensions allowing the standard MTD-2 and the load cell adapted MTD-2 to be used interchangably within the lab.
Although the MTD-2LC is designed specifically for the Futek LCM200 Load Cell, any other load cell with similar dimension that uses a standard US 3/8-24 thread at both ends of the load cell should work.