US 12,215,719 B2
Discretized valve state control for multi-level hydraulic systems
Michael Murphy, Arlington, MA (US); John Aaron Saunders, Arlington, MA (US); and Steven Potter, Bedford, MA (US)
Assigned to Boston Dynamics, Inc., Waltham, MA (US)
Filed by Boston Dynamics, Inc., Waltham, MA (US)
Filed on Jun. 14, 2023, as Appl. No. 18/335,016.
Application 15/465,415 is a division of application No. 14/447,796, filed on Jul. 31, 2014, granted, now 9,638,216, issued on May 2, 2017.
Application 18/335,016 is a continuation of application No. 17/184,434, filed on Feb. 24, 2021, granted, now 11,713,776.
Application 17/184,434 is a continuation of application No. 16/371,488, filed on Apr. 1, 2019, granted, now 10,962,033, issued on Mar. 30, 2021.
Application 16/371,488 is a continuation of application No. 15/465,415, filed on Mar. 21, 2017, granted, now 10,273,986, issued on Apr. 30, 2019.
Prior Publication US 2024/0026905 A1, Jan. 25, 2024
Int. Cl. F15B 11/18 (2006.01); B25J 9/14 (2006.01); B25J 9/16 (2006.01); B25J 9/20 (2006.01); F15B 11/16 (2006.01); F15B 11/17 (2006.01); G05D 1/00 (2006.01); G05D 16/20 (2006.01)
CPC F15B 11/18 (2013.01) [B25J 9/14 (2013.01); B25J 9/1633 (2013.01); B25J 9/1638 (2013.01); B25J 9/1697 (2013.01); B25J 9/20 (2013.01); F15B 11/161 (2013.01); F15B 11/162 (2013.01); F15B 11/17 (2013.01); G05D 1/0038 (2013.01); G05D 1/021 (2013.01); G05D 1/0246 (2013.01); G05D 16/2013 (2013.01); G05D 16/2022 (2019.01); B60Y 2400/406 (2013.01); F15B 2211/20592 (2013.01); F15B 2211/212 (2013.01); F15B 2211/30585 (2013.01); F15B 2211/40515 (2013.01); F15B 2211/41527 (2013.01); F15B 2211/41545 (2013.01); F15B 2211/455 (2013.01); F15B 2211/50 (2013.01); F15B 2211/605 (2013.01); F15B 2211/6306 (2013.01); F15B 2211/6313 (2013.01); F15B 2211/6336 (2013.01); F15B 2211/665 (2013.01); F15B 2211/6653 (2013.01); F15B 2211/6654 (2013.01); F15B 2211/7051 (2013.01); F15B 2211/71 (2013.01); F15B 2211/7107 (2013.01); F15B 2211/76 (2013.01); F15B 2211/765 (2013.01); F15B 2211/78 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A hydraulic drive system, comprising:
a hydraulic actuator;
a first pressure rail at a first pressure;
a second pressure rail at a second pressure different than the first pressure;
one or more selection valves;
a metering valve; and
a control system configured to:
receive data indicating a magnitude of a load on the hydraulic actuator;
determine an actuation pressure to actuate the load based on the magnitude of the load on the hydraulic actuator;
control the one or more selection valves to select one of the first pressure rail or the second pressure rail;
determine that a pressure difference between a pressure of the selected pressure rail and the determined actuation pressure exceeds a threshold pressure difference; and
based on determining that the pressure difference exceeds the threshold pressure difference, control the metering valve to throttle a flow of hydraulic fluid from the selected pressure rail to the hydraulic actuator such that the hydraulic fluid is at a throttled pressure that is within the threshold pressure difference from the determined actuation pressure.