Rotorcraft autopilot system, components and methods

• US 10,464,662 B2
• Filed: 08/22/2018
• Issued: 11/05/2019
• Est. Priority Date: 02/10/2012
• Status: Active Grant

• Current Assignee: Merlin Technologies Incorporated
• Original Assignee: Merlin Technologies Incorporated
• Inventors: Mercer, John E., Feifel, Marc, Marvin, Mark, Albion, Nicholas
• Primary Examiner(s): Luo, David
• Application Number:
  US16/109,170
• Publication Number:
  US 20180346110A1
• Time in Patent Office: 440 Days
• Field of Search: 318 3, 318 34
• CPC Class Codes: B64C 13/04 actuated personally
• CPC Class Codes: B64C 13/0421 control sticks for primary flight controls
• CPC Class Codes: B64C 13/18 using automatic pilot
• CPC Class Codes: B64C 13/30 using cable, chain, or rod mechanisms
• CPC Class Codes: B64C 13/343 overriding of personal controls; with automatic return to inoperative position
• CPC Class Codes: B64C 27/57 automatic or condition responsive, e.g. responsive to rotor speed, torque or thrust
• CPC Class Codes: B64C 27/58 Transmitting means, e.g. interrelated with initiating means or means acting on blades means acting on blades B64C27/72
• CPC Class Codes: F16F 15/121 using springs as elastic members, e.g. metallic springs F16F15/133 takes precedence
• CPC Class Codes: Y02T 50/40 Weight reduction

Abstract

An autopilot actuator includes first and second motors each including a rotatable motor output shaft such that either one or both of the motors can drive an actuator output shaft. An autopilot main unit enclosure is removably mounted to the helicopter proximate to a cyclic control and commonly houses autopilot actuators as well as main autopilot electronics. A cyclic vibration isolator is removably supported by an actuator shaft for co-rotation and coupled to the cyclic control to attenuate a cyclic vibration frequency at the actuator shaft while output rotations of the actuator shaft below a resonant frequency are coupled to the cyclic control. A force limited link includes first and second ends and a variable length between. The force limited link having a relaxed length when less than an unseating force is applied and the variable length changes when an applied force exceeds the unseating force to permit pilot override.

Claims

1. An autopilot system for a helicopter, comprising:

an autopilot display unit configured for mounting in an instrument console of the helicopter at least for displaying autopilot flight data to a pilot of the helicopter;

an autopilot main unit enclosure for removable mounting to the helicopter proximate to a cyclic control of the helicopter and which defines a main unit interior;

a set of actuators supported within the main unit interior including a pitch actuator having a pitch actuator output shaft and a roll actuator having a roll actuator output shaft such that no more than the pitch actuator shaft and the roll actuator shaft of the set of actuators extend at least partially outward from said autopilot main unit enclosure for providing mechanical control forces to the cyclic control of the helicopter; and

a main unit electronics section supported within said main unit interior and in electrical communication with said autopilot display unit and with said set of actuators such that the main unit electronics section and the set of actuators are commonly housed within the main unit interior.

2. The autopilot system of claim 1 wherein the main unit enclosure is L-shaped in a plan view.

3. The autopilot system of claim 2 wherein the main unit enclosure is configured for removable attachment to a pair of existing bulkheads of the helicopter without supplemental reinforcement of the existing bulkheads.

4. The autopilot system of claim 2 wherein the pitch actuator and the roll actuator are supported at opposing ends of the L-shape within the main unit interior.

5. The autopilot system of claim 1 wherein each actuator includes an actuator housing having an upper housing wall and a lower housing wall and the main unit enclosure includes an upper cover and a lower cover such that the actuator housing is supported in the main unit interior with the upper housing wall received against the upper cover and the lower housing wall received against the lower cover.

6. The autopilot system of claim 5 wherein each actuator housing includes a front housing wall and the actuator housing is supported in the main unit interior with the front housing wall received against a sidewall of the main unit enclosure which sidewall extends between the upper cover and the lower cover.

7. The autopilot system of claim 5 wherein the upper cover and the lower cover are each L-shaped.

8. The autopilot system of claim 5 wherein the upper housing wall of each actuator is removably attached to the upper cover and the lower housing wall of each actuator is removably attached to the lower cover.

9. The autopilot system of claim 5 wherein the main unit enclosure includes a first sidewall and a second sidewall each of which sidewalls maintain the upper cover and lower cover in a spaced apart relationship and the pitch actuator shaft extends through the first sidewall while the roll actuator shaft extends through the second sidewall.

10. The autopilot system of claim 9 wherein the main unit enclosure is configured for removable attachment to a pair of existing bulkheads of the helicopter without supplemental reinforcement of the existing bulkheads and the pitch actuator shaft extends through a first one of the bulkheads while the roll actuator shaft extends through a second one of the bulkheads.

11. The autopilot system of claim 1 wherein the main unit electronics section includes an inner loop that is configured to control at least approximately instantaneous attitude of the helicopter.

12. The autopilot system of claim 11 wherein the autopilot display unit includes an outer loop that is configured to issue navigation commands to the inner loop of the main unit electronics section.