Methods and apparatus for calculating routing arrangements for control cables

A method for calculating a routing arrangement for a control cable from a given cable length and a given condition for connecting the cable, the method comprising the steps of:

• obtaining a characteristic of a control cable;
• obtaining a characteristic of an outer terminal;
• and
• performing a numerical analysis by using the obtained characteristic of the control cable, the obtained characteristic of the outer terminal, the given cable length, and the given condition for connecting the cable,
• wherein at least a torsion characteristic of the outer terminal is obtained in the terminal characteristic obtaining step, and the method further comprises the steps of:
• (1) calculating the routing arrangement by conducting the performing step assuming that torque does not act on the outer terminal from the control cable;
• (2) calculating the torque, which acts on the outer terminal from the control cable, based upon the calculated routing arrangement;
• and
• (3) re-calculating the routing arrangement by conducting the performing step assuming that the calculated torque acts on the outer terminal.

A method for calculating a routing arrangement for a control cable from a given cable length and a given condition for connecting the cable, the method comprising the steps of:

• obtaining a characteristic of a control cable;
• obtaining a characteristic of an outer terminal;
• performing a numerical analysis by using the obtained characteristic of the control cable, the obtained characteristic of the outer terminal, the given cable length, and the given condition for connecting the cable;
• calculating the routing arrangement by conducting the performing step assuming that a force does not act on the outer terminal from the control cable;
• calculating the force, which acts on the outer terminal from the control cable, based upon the calculated routing arrangement;
• correcting the characteristic of the outer terminal to a characteristic that is obtained when the calculated force acts on the outer terminal;
• and
• re-calculating the routing arrangement by conducting the performing step using the corrected characteristic of the outer terminal.

A method for estimating durability of a control cable from a method for calculating a routing arrangement for a control cable from a given cable length and a given condition for connecting the cable, the method for calculating a routing arrangement for a control cable from a given cable length and a given condition for connecting the cable comprising the steps of:

• obtaining a characteristic of the control cable;
• and
• performing a numerical analysis by using the obtained characteristic of the control cable, the given cable length, and the given condition for connecting the cable;
• and
• the method for estimating durability of a control cable comprising the steps of:
• calculating bending stress, which acts on each part of the inner cable, based upon the calculated routing arrangement;
• calculating tensile stress or compressive stress that acts in the axial direction of the inner cable from a manipulating load;
• calculating composite stress on each point of the inner cable by using the calculated bending stress and the calculated tensile stress or compressive stress;
• calculating a stress amplitude of each point of the inner cable by using a manipulation movement and the calculated composite stress on each point of the inner cable;
• and
• evaluating the durability of the inner cable by comparing the calculated stress amplitude and a fatigue limit of the inner cable.

An apparatus for calculating a cable route for a control cable, comprising:

• means for entering a characteristic of the control cable;
• means for entering a length of the control cable;
• means for entering a condition for connecting the control cable, the entering condition means entering connecting positions for both ends of the control cable and a direction of a cable axis in each of the connecting positions;
• and
• means for calculating the cable route by performing a numerical analysis using the entered control cable characteristic, the entered control cable length, and the entered control cable connection condition, the calculating means calculating the cable route of the control cable in a case where the each ends of the control cable are fixed in the determined connecting positions and the determined directions of the cable axis, wherein the cable characteristic entering means enters a characteristic of an outer cable and a characteristic of an inner cable separately, and the cable route calculating means determines the characteristic of the control cable from the entered characteristics of the outer cable and inner cable and performs the numerical analysis by using the determined characteristic of the control cable.

A method for estimating durability of a control cable from a method for calculating a routing arrangement for a control cable from a given cable length and a given condition for connecting the cable, the method for calculating a routing arrangement for a control cable from a given cable length and a given condition for connecting the cable comprising the steps of:

• obtaining a characteristic of the control cable;
• and
• performing a numerical analysis by using the obtained characteristic of the control cable, the given cable length, and the given condition for connecting the cable,
• wherein the obtaining step comprises the steps of obtaining a characteristic of an outer cable and a characteristic of an inner cable separately, and determining the characteristic of the control cable from the obtained characteristics of the outer cable and inner cable;
• and
• the method for estimating durability of a control cable comprising the steps of:
• calculating bending stress, which acts on each part of the inner cable, based upon the calculated routing arrangement;
• calculating tensile stress or compressive stress that acts in the axial direction of the inner cable from a manipulating load;
• calculating composite stress on each point of the inner cable by using the calculated bending stress and the calculated tensile stress or compressive stress;
• calculating a stress amplitude of each point of the inner cable by using an manipulation movement and the calculated composite stress on each point of the inner cable;
• and
• evaluating the durability of the inner cable by comparing the calculated stress amplitude and a fatigue limit of the inner cable.

A method for estimating durability of a control cable from a method for calculating a routing arrangement for a control cable from a given cable length and a given condition for connecting the cable, the method for calculating a routing arrangement for a control cable from a given cable length and a given condition for connecting the cable comprising the steps of:

• obtaining a characteristic of a control cable;
• obtaining a characteristic of an outer terminal;
• and
• performing a numerical analysis by using the obtained characteristic of the control cable, the obtained characteristic of the outer terminal, the given cable length, and the given condition for connecting the cable;
• and
• the method for estimating durability of a control cable comprising the steps of:
• calculating bending stress, which acts on each part of the inner cable, based upon the calculated routing arrangement;
• calculating tensile stress or compressive stress that acts in the axial direction of the inner cable from a manipulating load;
• calculating composite stress on each point of the inner cable by using the calculated bending stress and the calculated tensile stress or compressive stress;
• calculating a stress amplitude of each point of the inner cable by using a manipulation movement and the calculated composite stress on each point of the inner cable;
• and
• evaluating the durability of the inner cable by comparing the calculated stress amplitude and a fatigue limit of the inner cable.

A method for calculating a cable route for a control cable, the method comprising the steps of:

• determining a cable length of the control cable;
• determining cable connecting conditions of the control cable, wherein the cable connecting conditions include connecting positions for both ends of the control cable and a direction of a cable axis in each of the connecting positions;
• obtaining a characteristic of the control cable;
• and
• performing a numerical analysis by using the obtained characteristic of the control cable, the determined cable length, and the determined cable connecting conditions, thereby calculating the cable route of the control cable in a case where each of the ends of the control cable are fixed in the determined connecting positions and the determined directions of the cable axis, wherein the cable connecting conditions further include a position of a clamping point, at which the control cable is clamped, and clamping conditions for the clamping point.

A method for calculating a cable route for a control cable, the method comprising the steps of:

• determining a cable length of the control cable;
• determining cable connecting conditions of the control cable, wherein the cable connecting conditions include connecting positions for both ends of the control cable and a direction of a cable axis in each of the connecting positions;
• obtaining a characteristic of the control cable;
• and
• performing a numerical analysis by using the obtained characteristic of the control cable, the determined cable length, and the determined cable connecting conditions, thereby calculating the cable route of the control cable in a case where each of the ends of the control cable are fixed in the determined connecting positions and the determined directions of the cable axis, the method further comprising the steps of calculating a total bending angle from the calculated cable route and calculating a load efficiency of the control cable.