Utility arm

A utility arm comprising

• a first arm, terminating in first universal joint, locked by a first piston
• a second arm, terminating in second universal joint, locked by a second piston
• an intermediate joint positioned between the first universal joint and second universal joint
• a locking means on the intermediate joint
• the intermediate joint including
• the intermediate join acting on the first piston to lock the first universal joint
• the intermediate join acting on the second piston to lock the second universal joint;
• wherein at least one of the pistons includes a resilient compression member.

A utility arm comprising

• a first arm, terminating in first universal joint, locked by a first piston
• a second arm, terminating in second universal joint, locked by a second piston
• an intermediate joint positioned between the first universal joint and second universal joint
• a locking means on intermediate joint
• the intermediate joint including
• a first housing, with first pressure piece having an inclined surface which abuts the first piston
• a second housing, with second pressure piece having an inclined surface which abuts the second piston
• wherein the first housing and the second housing are spaced apart when the intermediate joint is unlocked, and come together when the intermediate joint is locked to give a visual indication of the state of the intermediate joint.

A utility arm comprising

• a first arm, terminating in first universal joint, locked by a first piston
• a second arm, terminating in second universal joint, locked by a second piston
• an intermediate joint positioned between the first universal joint and second universal joint
• a locking means on intermediate joint
• the intermediate joint including
• a first housing, with first pressure piece having an inclined surface which abuts the first piston
• a second housing, with second pressure piece having an inclined surface which abuts the second piston
• the first pressure piece and second pressure piece interfering with the application of pressure by the action of the locking means, such that the inclined surface of the first pressure piece acts on the first piston to lock the first universal joint, the inclined surface of the second pressure piece acts on the second piston to lock the second universal joint, the first pressure piece having a rotationally asymmetric shape and sliding within a substantially corresponding channel in the first housing so as to be constrained the first pressure piece from relative rotation

A utility arm comprising

• a first arm, terminating in first universal joint, carrying a payload
• a second arm, terminating in second universal joint
• an intermediate joint positioned between the first universal joint and second universal joint
• wherein the first universal joint has a first torque resistance, the intermediate joint has a second torque resistance, and the second universal joint has a third torque resistance, the ratio of the first, second and third torque resistances being substantially in proportional to the ratio of the distances from the payload.