Downloading New Earthquakes - Quanser 6 DOF Hexapod Laboratory Manual

The default values used for the PID gains and cut-off filter are:
The cut-off frequency, ω , is for the second-order filter that is used to compute the desired joint velocity and accel-
eration.
Caution: These are the default PD control gains that are used in the 6 DOF Hexapod software controller
and should NOT be tuned by the user unless it is necessary for application-specific reasons.

3.3 DOWNLOADING NEW EARTHQUAKES

There are a variety of resources on the Internet where real earthquake data can be downloaded. This section
explains how to download and use the records from the Pacific Earthquake Engineering Research Center (PEER)
Ground Motion Database website at:
On the PEER website, each earthquake has various measurement stations and each station contains recorded
displacement, velocity, and acceleration data of the tremor at different directions. The default download setting is
acceleration, which is required when using the supplied make_quake_xyz.m file. To illustrate how to download and
run an earthquake, the procedure below shows how to find the Kobe tremor recorded at the HIK station:
1. Go to the PEER Ground Motion Database at:
2. Click on the Unscaled button.
3. In the Event Name field, enter Kobe, Japan as illustrated in Figure 3.2.
Figure 3.2: Searching for the Kobe earthquake on PEER Ground Motion Database
4. Click on Search.
5. As shown in Figure 3.3, the Results section displays all the stations that recorded the Kobe earthquake.
6. Select Result #2 to download the recorded Kobe acceleration that was measured at the HIK station.
N/m
k = 30000
N/(m-s)
k = 40000
N-s/m
k = 3000
rad/s
ω = 1000
HEXAPOD Laboratory Guide 24