Systems and methods according to present principles provide for three axis force sensing in a convenient and manufacturable way. In one implementation, a vibrating motor is attached at the fixed end of an anisotropic structure, such as a rod, which then vibrates in a circular motion. A monitor such as a 3-axis accelerometer is also attached to the anisotropic structure. The resulting motion is then mapped electronically for analysis. With no force applied, a circular motion is achieved. When a net force is applied to the free, vibrating end of the rod, the circular pattern which is traced out becomes distorted, e.g., progressively flattened into an ellipse, in a repeatable way which is directly proportional to the applied force. The axis of the applied force can be ascertained according to the direction in which the ellipse forms. Systems and methods according to present principles may be used in any application in which force sensing is needed, e.g., robotics, including robotic surgery.

Systems and methods according to present principles provide for three axis force sensing in a convenient and manufacturable way. In one implementation, a vibrating motor is attached at the fixed end of an anisotropic structure, such as a rod, which then vibrates in a circular motion. A monitor such as a 3-axis accelerometer is also attached to the anisotropic structure. The resulting motion is then mapped electronically for analysis. With no force applied, a circular motion is achieved. When a net force is applied to the free, vibrating end of the rod, the circular pattern which is traced out becomes distorted, e.g., progressively flattened into an ellipse, in a repeatable way which is directly proportional to the applied force. The axis of the applied force can be ascertained according to the direction in which the ellipse forms. Systems and methods according to present principles may be used in any application in which force sensing is needed, e.g., robotics, including robotic surgery.

An axle assembly for a bicycle includes an axle having an inner wall extending along a length of the axle between a first end and a second end of the axle. The inner wall at least partially defines a first volume and a second volume within the axle. The first volume has a first diameter, and the second volume has a second diameter that is greater than the first diameter. The first volume is closer than the second volume to the first end of the axle. The axle assembly also includes a sensor attached to the inner wall of the axle within the second volume of the axle.

Sensor system comprising a frame supporting a force-sensing tip arranged to generate a signal based upon a force applied by said force-sensing tip to a material to be tested, the system further comprising: an input drum mounted in said frame such that it can rotate about an input axis of rotation; an output lever supported by said frame by means of an output revolute joint defining an output axis of rotation;
wherein said force-sensing tip is mounted on said output lever such that said force-sensing tip is arranged to be brought into contact with a material to be tested;
and wherein said sensor system comprises a mechanical transmission arranged to kinematically link said input drum to said output lever such that a rotation of said input drum about said input axis of rotation causes said output lever to pivot in an oscillatory manner about said output axis of rotation.

A highly accurate torque sensor is provided by reducing the size of the shape. A torque sensor comprises a fourth structure and a fifth structure provided between a first structure and a second structure, a first strain sensor provided on the fourth structure, and a second strain sensor provided on the fifth structure. Each of the fourth structure and the fifth structure comprises a first connection section connected to one end of the first strain sensor or the second strain sensor, a second connection section connected to the other end of the first strain sensor or the second strain sensor, and a third connection section and a fourth connection section provided between the first connection section and the second connection section and possessing stiffness lower than the first connection section and the second connection section.

A highly accurate torque sensor is provided by reducing the size of the shape. A torque sensor comprises a fourth structure and a fifth structure provided between a first structure and a second structure, a first strain sensor provided on the fourth structure, and a second strain sensor provided on the fifth structure. Each of the fourth structure and the fifth structure comprises a first connection section connected to one end of the first strain sensor or the second strain sensor, a second connection section connected to the other end of the first strain sensor or the second strain sensor, and a third connection section and a fourth connection section provided between the first connection section and the second connection section and possessing stiffness lower than the first connection section and the second connection section.

A method and robot controller configured to obtain an inertia-vibration model of the robot arm. The inertia-vibration model defines a relationship between the inertia of the robot arm and the vibrational properties of said robot arm and have been by setting the robot arm in a plurality of different physical configurations and for each of said physical configurations of said robot arm obtaining the vibrational properties and the inertia the robot arm. The inertia-vibration model makes it possible to in a simple and efficient way to obtain the vibrational properties of different physical configurations of the robot arm whereby the robot arm can be controlled according to the vibrational properties of the robot arm. This makes it possible to reduce the vibrations of the robot arm during movement of the robot arm.

A method and robot controller configured to obtain an inertia-vibration model of the robot arm. The inertia-vibration model defines a relationship between the inertia of the robot arm and the vibrational properties of said robot arm and have been by setting the robot arm in a plurality of different physical configurations and for each of said physical configurations of said robot arm obtaining the vibrational properties and the inertia the robot arm. The inertia-vibration model makes it possible to in a simple and efficient way to obtain the vibrational properties of different physical configurations of the robot arm whereby the robot arm can be controlled according to the vibrational properties of the robot arm. This makes it possible to reduce the vibrations of the robot arm during movement of the robot arm.

A load calculator includes a coefficient storage, a replacement deriver, and an internal-load deriver. The storage stores a first coefficient, an internal load acting on a target point in a target member when a unit load acts on a concentrated load point in the target member along one of three orthogonal axes, and as a second coefficient, an internal load acting on the target point when a unit moment acts on the concentrated load point around one of the axes. The replacement deriver derives a replacement load and moment by replacing an external load acting on the target member with six force components acting on the concentrated load point. The internal load deriver derives an internal load acting on any target point with the first coefficient, the replacement load, the second coefficient, and the replacement moment when the external load acts on the target member.

A load calculator includes a coefficient storage, a replacement deriver, and an internal-load deriver. The storage stores a first coefficient, an internal load acting on a target point in a target member when a unit load acts on a concentrated load point in the target member along one of three orthogonal axes, and as a second coefficient, an internal load acting on the target point when a unit moment acts on the concentrated load point around one of the axes. The replacement deriver derives a replacement load and moment by replacing an external load acting on the target member with six force components acting on the concentrated load point. The internal load deriver derives an internal load acting on any target point with the first coefficient, the replacement load, the second coefficient, and the replacement moment when the external load acts on the target member.