This dataset is a collection of measurements performed with smartphone inertial sensors. An Android application was created to record triaxial acceleration, speed, and rotational speed (when gyroscopes were available in the device) while a vehicle was driven and a pothole, speed bump, or line of metal speed bumps were passed. Several smartphones, placed in different locations inside the vehicle, were sensing at the same time.
Data was collected in Chihuahua, Mexico, during June 2018 in eight collection sessions using eight different vehicles:
| Date | Vehicle |
|---|---|
| 2018-06-12 | Honda Accord 2007 |
| 2018-06-14 | Chevrolet Express van 2013 |
| 2018-06-18 | Chevrolet Spark 2013 |
| 2018-06-20 | Peugeot Partner 2013 |
| 2018-06-22 | Chevrolet Cruze 2010 |
| 2018-06-25 | VW Derby 2001 |
| 2018-06-27 | Kia RIO 2018 |
| 2018-06-29 | VW Pointer 2004 |
All samples were collected under good weather conditions over dry streets paved with asphalt. The sampling rates for both the accelerometer and gyroscope were set to 50 Hz.
Data is presented in the HDF5 hierarchical format, for which viewers and APIs are readily available.
Individual samples are found under the /samples branch, each identified by a UUID, and raw readings are presented in the X, Y, Z axes with respect to the smartphone frame of reference (i.e. no reorientation or preprocessing was performed). Samples contain the following attributes:
| Attribute name | Meaning |
|---|---|
| Type | The type of road anomaly that was sampled (pothole, speed bump (asphalt), metal bumps, and a few instances of other types |
| Vehicle | The vehicle driven when the sample was captured |
| Placement | The location of the smartphone inside the vehicle for that data collection session |
| Speed | The average speed for that sample, as registered by the smartphone, in km/h (some times being zero) |
| Event | Since several devices were collecting data simultaneously, this ID is used to group samples that were registered at the same time |
| Depth | The depth of a pothole (in cm) |
| Dim1 | Potholes were modeled as having an elliptical shape, and this attribute indicates the major axis of the ellipse (in cm) |
| Dim2 | The minor axis of the ellipse |
| Condition | Speed reducers have this attribute, indicating if the speed reducer was considered to be in “good” or “bad” condition (“good” being considered as being capable of performing its intended purpose and “bad” being considered as an example of an ineffective speed reducer) |
For convenience, the /idx branch presents groups of links that can be used as indices to access some specific subsets:
| Index name | Referenced samples |
|---|---|
| Type | The available samples for each type of road anomaly |
| Placement | Samples grouped by the location of the smartphone inside the car |
| Gyroscope | The samples that contain rotational speed data |
| Event | The groups of samples that were registered simultaneously |
| Vehicle | Samples grouped by the vehicle that was driven when data was recorded |