US: Juniper Systems, a US-based manufacturer of rugged handheld computers and rugged PDAs for mobile data collection in extreme environments, has developed an app that works with its rugged Mesa Geo notepad to analyse and reduce GPS errors.
The app allows the users to tell their devices about the activities they are performing. This prompts the GPS receiver to try and figure out the user’s actual position when a signal is corrupted by objects. In case the user is walking with the device, the system will assume a very low acceleration. Thus it won”t indicate that the person is farther away from the last known location than he could reasonably walk. Similarly, there is another setting for use in a vehicle which estimates positions that might be quite a distance horizontally from where the user started out, but probably about the same spot vertically. There is also an ‘At Sea’ mode which assumes no vertical change in position, but it allows a lot of horizontal movement. The ‘Static Hold’ mode is used when the user plans to stand still for a long period of time, or if the device itself is placed in one spot. The navigation algorithm”s velocity is set to zero along both the horizontal and vertical axis, and it will remain stable until evidence of movement is detected.