Personal Inertial Navigation System (PINS)
Project Goals
Accomplishments
- Create an integrated inertial measurement unit (IMU) and three-axis magnetometer that can be mounted at the level of the boot.
- Create software for processing the IMU data such that the pauses between each step and the next are identifiable (identifying zero velocity).
- Create software that regards each step as a separate mini-trip with its own mini-initialization. Combine these mini-trips into a single trip. (Using zero velocity observations to update the navigation calculations is known as Zero velocity UPdaTing, or ZUPTing.)
- Demonstrate that the achievable overall accuracy is useful for some military purposes. The initial accuracy goal is an error growth rate not greater than about one foot per minute.
- Integrate the PINS IMU with the Battelle Advanced Binocular System using BBN BodyLAN.
Milestones
- Zero velocity has been reliably detected by an algorithm operating on the IMU data stream.
- ZUPTing has been shown to work as expected, thereby enabling major reductions in the error growth rate.
- Computational accuracies using a COTS IMU, without using any magnetometer data, are approaching the near-term accuracy goal (within a factor of 2). (The COTS IMU is too big and too heavy for fielding.)
- A small, light, low-powered IMU/magnetometer ("PINSPak") has been designed and is in PCB layout (5/12/97).
- A third iteration of a boot mounting for the IMU/magnetometer has been designed and is now being fabricated.
Near Term
Within the term of the contract
Long Term
- Demonstrate the validity of the ZUPTing idea as an enabling technology for on-foot personal inertial navigation.
- Demonstrate a means for mounting the IMU at boot level that is operationally feasible for the wearer while still accurate enough for useful navigation.
- Create an IMU using COTS sensors that is acceptably small, light-weight, low powered, and accurate.
- Demonstrate the user's navigation via a display carried by the user.
Beyond the term of the contract
- Integrate the PINS system with a GPS system.
- Integrate the PINS system with a communication link so that the movements of the wearer are known immediately by others remote from the wearer.
- Include site-specific geographic/geometric information as part of the data processing steps so that the user's calculated movements are consistent with known physical constraints.