Andrew S. Klane and Mario Gosalvez
Purpose-built rugged tablets designed with specific capabilities for certain tasks can save both time and money while driving superior outcomes.
With the recent advent of GNSS (Global Navigation Satellite System) RTK (Real-Time Kinematic) rugged tablets, forensic mapping is being revolutionized. These new tablets enable something previously not possible: scientific-grade accurate measurements for those engaged in non land surveying work. These rugged tablets can deliver centimeter level measurement accuracy faster and easier than using conventional land surveying equipment and at a fraction of the cost – which, in turn, improves safety for first responders during collision reconstruction, natural disasters and crime scenes.
For example, by utilizing this new technology, law enforcement personnel can obtain the necessary measurements to recreate crime scenes in legal settings with precise accuracy to meet the requirements of the rules of evidence. They can capture and process three-dimensional data more quickly to reinforce public safety in situations where it might otherwise be compromised. By deploying GNSS-RTK rugged tablets with drones for increased speed and portability, users get the added benefits of protecting the environment and leveraging user-friendly equipment to obtain the necessary data to support contemporary law enforcement.
The centimeter level measurement accuracies of forensic mapping with rugged tablets are possible through GNSS with RTK functionality which includes multiple constellations – GPS (USA), GLONASS (Russian) and Beidou (China). These technologies are useful for either primary mapping or ground control when deploying drones. The latter method is particularly effective due to its incorporation of aerial photogrammetry which enables users to rapidly take multiple photos of crime scenes supported by software.
These devices then process those pictures with software which reconstructs the scene in a 3-D environment or “point cloud.” The RTK GPS is able to refine the accuracy of the aircraft – which is approximately three meters –to centimeters by reliably positioning the coordinates of the data points in the real world. The tablets contain the storage, computing power and software to quickly complete these procedures.
Survey-grade accuracy is beneficial in documenting crime scenes (including motor vehicle crashes) because it increases their influence in court. Images must be considered scientifically valid for jurors to use them during deliberations; consistent centimeter level accuracy increases the likelihood of including forensic models in this process. This approach allows users to document anything from static crime scenes to the speed of a car in a crash. Comparable methods relying on laser scanners may cost five times as much.
Rapid Data Collection
The expedience of deploying these rugged tablets and drones for forensic mapping far exceeds that of using other equipment – especially for reconstructing motor vehicle crashes which may close highways or roads for long periods of time. In these instances, it is vital to rapidly collect accurate data, clear the scene and relieve traffic congestion. Most US states are involved in Traffic Incident Management initiatives overseen by the Federal Highway Administration (FHA) which assists in purchasing equipment and technology to facilitate the quick clearance of these traffic-related incidents. States may also be eligible for grants if they demonstrate the need for equipment which improves incident management and traffic safety.
Significantly, the same forensic mapping work which would take three hours using conventional total station equipment would take two hours relying on GPS systems. One can complete the same task in 20-30 minutes by combining GNSS-RTK rugged tablets with drones, hastening the way to clearing the road so transit resumes.
Improved Public Safety
Perhaps the most notable advantage of pairing these rugged tablets with drones to expedite accurate forensic mapping is increasing public safety. Oftentimes, there is a direct correlation between conserving time for roadway incidents and saving lives.
Data supported by the FHA indicates the chance of a secondary collision increases approximately three percent every minute the initial one has yet to be cleared. Secondary crashes total about 20 percent of motor vehicle crashes across the nation, resulting in roughly 18 percent of interstate highway fatalities. Victims of secondary crashes not only include additional motorists, pedestrians and travelers, but also first responders like law enforcement personnel, EMTs and rescue personnel.
By decreasing the time for the forensic mapping of collision scenes by a half or even a third – yielding similar gains for the time it takes to clear these incidents altogether – law enforcement could create a tremendous impact on saving the lives of workers attempting to clear those scenes, as well as on travelers who happen to be in the wrong place at the wrong time.
Conducting forensic mapping with GNSS-RTK rugged tablets and drones grants users many more benefits than the three identified in this article. This equipment is exceedingly user-friendly, significantly decreasing the time and financial resources necessary to train operators. The speed at which crime scene data is collected also translates into environmental boons, since this process is often the first step in actually clearing the scene and reducing the smog and pollution caused by crashes – or numerous motorists idling their vehicles in the wake of collisions.
By implementing accurate forensic mapping in rapid time frames, this technology is able to improve all these downstream effects and the primary one – obtaining accurate data at crime scenes.
Andrew S. Klane is a former Massachusetts State Police Lieutenant who teaches Forensic Mapping and is COO at Forensic Mapping Solutions Inc.
Mario Gosalvez is Business Development Manager at DT Research, a market leading designer and manufacturer of purpose-built computing solutions for vertical markets.