INNALABS designs, produces and manufactures: single- and two-axis Coriolis Vibratory Gyroscopes (CVG) for stabilization applications.

Technology Review. INNALABS presents new development: Coriolis Vibratory Gyroscopes (CVG) which are based on the control of two standing waves in a physical body. This body is a resonator which can be designed as an axisymmetrical shape or not, but only axisymmetrical shapes lead to top of the range performances. This breakthrough technology allowed substantially increase product life of the gyroscopes (MTBF > 500,000 hours) and their shock resistance (300g, 2 to 5ms). Along with these, INL-CVG gyroscopes achieved the highest Bias stability and the lowest noise among competitors in the market sector. Picture on the right shows INNALABS’ INL-CVG sensitive element which contains a resonator. This sensitive element is used whatever INNALABS’ products.

The resonator is operated on its second order resonant modes. Standing waves are therefore elliptical shape oscillations with four antinodes and four nodes located circumferentially along the rim, angle between two adjacent antinode – node being 45 deg. One of the elliptical resonant modes is excited to a prescribed amplitude. When the device rotates about its sensitive axis (along its inner stem), the resulting Coriolis forces acting on the resonator’s vibrating mass elements excite the second resonant mode. Angle between major axis of the two modes is 45 deg. A closed-loop drives the second resonant mode to zero and the force required to null this mode is proportional to the input rotation rate. Corresponding control loop system is called force-rebalanced mode. In order to provide forces and to sense induced motions, piezo-electric elements placed on the resonator are used. This electromechanical system is particularly effective and leads to low output noise and large dynamic range as required in case of demanding applications.

Applications. INNALABS’ INL-CVG gyroscopes will be found for example in the following very demanding applications, such as Platforms stabilization, Positioning and Stabilized Pointing, Gyro-stabilized balls, EO/FLIR stabilization, Railways tilt systems, Sonar stabilization, APS and DIRCM stabilization, Autopilot sensing and control, Midcourse guidance, Motion compensation, Inertial measurement units (IMU), Inertial Navigation Systems (INS & INS/GPS), Automated Guided Vehicles (AGV), Unmanned Underwater Vehicles (UUV), Unmanned Aerial Vehicles (UAV), Remotely Operated underwater Vehicles (ROV).

Click to enlarge the CVG Damper Drawing