An apparatus comprising: a downhole tool operable to be coupled with a tool string and conveyed within a downhole passage, wherein the downhole passage is a wellbore or a tubular member disposed in the wellbore, and wherein the downhole tool comprises: a first support member (316, 318); a second support member (316, 318); and a plurality of arms each comprising: a first arm member (319, 320) pivotably connected with the first support member via a first pivot joint (321-324, 326-329); and a second arm member (319, 320) pivotably connected with the second support member via a second pivot joint (321-324, 326-329), wherein the first and second arm members are pivotably connected via a third pivot joint; characterized in that: for each of the arms: the first and second pivot joints are azimuthally misaligned around a central axis of the downhole tool; the first and second pivot joints are located on a first side of a plane (346, 348) coinciding with the central axis of the downhole tool; and the third pivot joint is located on a second side of the plane coinciding with the central axis of the downhole tool opposite the first side; and the downhole tool further comprises an actuator operable to cause the plurality of arms to: move against a sidewall of the downhole passage to centralize at least a portion of the tool string within the downhole passage; impart an intended force against the sidewall of the downhole passage; and maintain the intended force while the tool string is conveyed along the downhole passage and an inner diameter of the downhole passage changes. a downhole tool operable to be coupled with a tool string and conveyed within a downhole passage, wherein the downhole passage is a wellbore or a tubular member disposed in the wellbore, and wherein the downhole tool comprises: a first support member (316, 318); a second support member (316, 318); and a plurality of arms each comprising: a first arm member (319, 320) pivotably connected with the first support member via a first pivot joint (321-324, 326-329); and a second arm member (319, 320) pivotably connected with the second support member via a second pivot joint (321-324, 326-329), wherein the first and second arm members are pivotably connected via a third pivot joint; a first support member (316, 318); a second support member (316, 318); and a plurality of arms each comprising: a first arm member (319, 320) pivotably connected with the first support member via a first pivot joint (321-324, 326-329); and a second arm member (319, 320) pivotably connected with the second support member via a second pivot joint (321-324, 326-329), wherein the first and second arm members are pivotably connected via a third pivot joint; a first arm member (319, 320) pivotably connected with the first support member via a first pivot joint (321-324, 326-329); and a second arm member (319, 320) pivotably connected with the second support member via a second pivot joint (321-324, 326-329), wherein the first and second arm members are pivotably connected via a third pivot joint; characterized in that: for each of the arms: the first and second pivot joints are azimuthally misaligned around a central axis of the downhole tool; the first and second pivot joints are located on a first side of a plane (346, 348) coinciding with the central axis of the downhole tool; and the third pivot joint is located on a second side of the plane coinciding with the central axis of the downhole tool opposite the first side; and the downhole tool further comprises an actuator operable to cause the plurality of arms to: move against a sidewall of the downhole passage to centralize at least a portion of the tool string within the downhole passage; impart an intended force against the sidewall of the downhole passage; and maintain the intended force while the tool string is conveyed along the downhole passage and an inner diameter of the downhole passage changes. for each of the arms: the first and second pivot joints are azimuthally misaligned around a central axis of the downhole tool; the first and second pivot joints are located on a first side of a plane (346, 348) coinciding with the central axis of the downhole tool; and the third pivot joint is located on a second side of the plane coinciding with the central axis of the downhole tool opposite the first side; and the first and second pivot joints are azimuthally misaligned around a central axis of the downhole tool; the first and second pivot joints are located on a first side of a plane (346, 348) coinciding with the central axis of the downhole tool; and the third pivot joint is located on a second side of the plane coinciding with the central axis of the downhole tool opposite the first side; and the downhole tool further comprises an actuator operable to cause the plurality of arms to: move against a sidewall of the downhole passage to centralize at least a portion of the tool string within the downhole passage; impart an intended force against the sidewall of the downhole passage; and maintain the intended force while the tool string is conveyed along the downhole passage and an inner diameter of the downhole passage changes. move against a sidewall of the downhole passage to centralize at least a portion of the tool string within the downhole passage; impart an intended force against the sidewall of the downhole passage; and maintain the intended force while the tool string is conveyed along the downhole passage and an inner diameter of the downhole passage changes.