DETAILED ACTION
The present application, filed on or after March 16, 2013, is being examined under the first inventor to file provisions of the AIA .
Continued Examination Under 37 CFR 1.114
A request for continued examination under 37 CFR 1.114, including the fee set forth in 37 CFR 1.17(e), was filed in this application after final rejection. Since this application is eligible for continued examination under 37 CFR 1.114, and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114. Applicant's submission filed on 12/30/2025 has been entered.
Claim Objections
Claim 10 is objected to because of the following informalities:
change claim 10 line 7 accordingly: “generated by the at least one [[of]] rotor”
Appropriate correction is required.
Claim Rejections - 35 USC § 112
The following is a quotation of 35 U.S.C. 112(b):
(b) CONCLUSION.—The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the inventor or a joint inventor regards as the invention.
The following is a quotation of 35 U.S.C. 112 (pre-AIA ), second paragraph:
The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the applicant regards as his invention.
Claims 1 and 5-9 are rejected under 35 U.S.C. 112(b) or 35 U.S.C. 112 (pre-AIA ), second paragraph, as being indefinite for failing to particularly point out and distinctly claim the subject matter which the inventor or a joint inventor (or for applications subject to pre-AIA 35 U.S.C. 112, the applicant), regards as the invention.
Claim 1 recites the limitation "the noise produced by rotation of the first rotor and the second rotor in combination" in lines 15-16 . There is insufficient antecedent basis for this limitation in the claim.
Claim 1 recites the phrase “based on the position and an operational parameter of the first rotor and the second rotor, respectively” in lines 12-13. It appears the metes and bounds of the instant phrase are unclear in light of correspondence with applicant specification (MPEP 2173.03). The plain meaning1 of the instant phrase is using the position of the first rotor and an operational parameter of the second rotor. However this is in contrast with applicant par. 39 that points out that the instant position and operational parameter are with regard to the same rotor. The claim is interpreted is consistent with par. 39 such that the claim only requires estimating noise of one rotor (of the first and second rotors) based on the position and operational parameter of the one rotor. Par. 39 includes approximating the noise for the fan rotor of each fan stage 60,62. However claim 1 does not require this (i.e. claim 1 recites “estimate a noise generated by at least one of the first rotor and the second rotor”) and it is improper to import limitations from the specification into the claims.
Claims dependent thereon are rejected for the same reasons.
Claim Rejections - 35 USC § 103
The following is a quotation of 35 U.S.C. 103 which forms the basis for all obviousness rejections set forth in this Office action:
A patent for a claimed invention may not be obtained, notwithstanding that the claimed invention is not identically disclosed as set forth in section 102, if the differences between the claimed invention and the prior art are such that the claimed invention as a whole would have been obvious before the effective filing date of the claimed invention to a person having ordinary skill in the art to which the claimed invention pertains. Patentability shall not be negated by the manner in which the invention was made.
The factual inquiries for establishing a background for determining obviousness under 35 U.S.C. 103 are summarized as follows:
1. Determining the scope and contents of the prior art.
2. Ascertaining the differences between the prior art and the claims at issue.
3. Resolving the level of ordinary skill in the pertinent art.
4. Considering objective evidence present in the application indicating obviousness or nonobviousness.
Claim(s) 1, 5-10 and 14-20 is/are rejected under 35 U.S.C. 103 as being unpatentable over Pub. No.: US 2022/0194557 A1 (Thomas) in view of US 2013/0106333 A1 (Durkee) and Pub. No.: US 2016/0083073 A1 (Beckman).
Regarding claim 1, Thomas discloses (see figs. 1-3, 6, 7, 9 and 11) a propulsion system 12 comprising: a propulsion unit 42A,42B including a multi-stage fan (see blades 44A,44A’,44B,44B’ in fig. 6) having a first fan stage including a first rotor 42A and a second fan stage including a second rotor 42B; at least one propulsion motor 48A,48B operably coupled (via shafts 50A,50B in fig. 6) to the first rotor and the second rotor to drive the first rotor and the second rotor about a fan axis A;
a controller 24,54A,54B (see fig. 7) configured to:
determine a position of at least one of the first rotor and the second rotor in response to an electrical signature (“output waveforms” from the motors can be the “rotation angle sensors”, see par. 31, communicates “rotation angle of the first and second motors” to instant controllers, see par. 29 and fig. 7 showing example controller 54A and rotation angle sensor 56A; the relative positions of the instant blades on the rotors is then determined in order to regulate the phase as an operating parameter in order to reduce noise, see pars. 10, 39 and 41, and see figs. 4-5 showing differing phase differential angles [Symbol font/0x6A]) of the at least one propulsion motor 48A,48B; and
(evaluate2) (see par. 41: “the computer may adjust the setpoint in an open-loop manner based on one or more sensed or predicted parameter values. Suitable parameter values include rotational velocity of the rotors”; one of ordinary skill would understand that phase [Symbol font/0x6A] and rotational velocity of the rotor correspond with noise; Thomas points out in par. 41 that in order to “reduce the amount of acoustic noise” of the rotors, see par. 18, bottom, the phase differential angle [Symbol font/0x6A] is set by the rotor velocity, the phase differential angle being the difference in “positions” of the two rotors and such phase difference is determined based on sensing the position of each rotor; as general information one of ordinary skill understands when reading Thomas par. 40 that there is a database or table correlating phase differential angle [Symbol font/0x6A] and velocity with a particular noise level and such a table or database is developed by empirical measurements that determines an estimated noise level of each phase angle [Symbol font/0x6A] for particular rotor velocities and this is explained in more detail in pertinent prior art (PPA) infra that explains knowledge of the ordinary worker in the instant art; the PPA explains how the Thomas par. 41 open loop algorithm, or lookup table, is developed and also explains how one of ordinary skill would understand applicant par. 39 database is developed; it is noted that there is no disclosure in applicant specification of a particular algorithm, other than the database, of how the claimed noise estimate is arrived at) a noise generated by at least one of the first rotor 42A and the second rotor 42B based on the position (this position of each rotor is used to determine the phase differential angle [Symbol font/0x6A] that is used in the claimed “estimate a noise” as explained above) and an operational parameter (rotor velocity; see par. 41) of the first rotor and the second rotor, respectively (this is interpreted as explained in the 112 section above);
The setting of the phase differential angle [Symbol font/0x6A] in Thomas par. 41 (i.e. moving the rotors so as to arrive at the phase differential angle [Symbol font/0x6A] setpoint is done to reduce noise) is an evaluation of noise. For example, one phase differential angle [Symbol font/0x6A] setpoint results in a different noise than another phase differential angle [Symbol font/0x6A] setpoint. This is an evaluation of noise because it evaluates the noise of Thomas and because such phase differential angle [Symbol font/0x6A] setpoint is set using the rotor velocity when a direct measurement of noise is not used (see par. 41: “In some examples, the onboard computer may receive input from an onboard microphone and adjust the [phase differential angle [Symbol font/0x6A] ] setpoint in a closed-loop manner so as to reduce the amount noise. In other examples, the computer may adjust the setpoint in an open-loop manner based on … parameter values include rotational velocity of the rotors”).
in response to the noise, adjust one or more operating parameters ((1)3 phase differential angle, rotational velocity of instant rotors 42A,42B, see pars. 21, 29 and 41, during powered operation of the electric motors for example during VTOL operations using propulsion systems 12 that include the instant motors 48A,48B and rotors 42A,42B; for example, positions of the first 42A and second 42B rotors of Thomas are used reduce noise or acoustic emissions by way of setting the differential phase angle [Symbol font/0x6A] between the positions of the first rotor 42A and the second rotor 42B wherein the differential phase angle [Symbol font/0x6A] is determined by measuring the positions of the first rotor 42A and the second rotor 42B and discussed earlier in this claim analysis (i.e., electric signal from sensors 56A,56B communicates “rotation angle of the first and second motors”, or in other words the position of the rotor, to instant controllers, see par. 29 and fig. 7; the relative positions of the instant blades 44A,44B on the rotors 42A,42B is then determined in order to regulate the phase as an operating parameter in order to reduce noise, see pars. 10, 39 and 41, and see figs. 4-5 showing differing phase differential angles [Symbol font/0x6A]; and (2)4 alignment of the blades with ambient wind during cruise of the aircraft 10, see pars. 26 and 42, wherein non-alignment of blades causes noise as pointed out in par. 24, such that the instant motors 48A,48B must adjust all the blades to be aligned to the wind to reduce drag on the aircraft; as pointed out in par. 24 whenever the “position” of the rotors 42A,42B are such that blades are not aligned with the wind direction, then this is representative of a noise condition; therefore for example on a day when the wind is aligned with the longitudinal axis of the pylon (see annotated figure below) the position of some blades would represent noise (see par. 24 and see annotated blades below in path of lateral airflow); the motors can change the position of the instant blades to be more aligned with the wind direction (see annotated figures below) based on the position of the lateral blade oriented blade below causing drag (the position being an estimate of noise of Thomas wherein the noise is reduced by the instant aligning, see step 90 in fig. 9); thus during vertical flight of scenario (1), the phase difference [Symbol font/0x6A] between the two rotors are changed, see figs. 4-5, to reduce noise, and during horizontal cruise flight of scenario (2), wherein aircraft propulsion is accomplished by aft engine 20, the phase differential of the instant rotors is zero, see fig. 2, and the position of all the blades together are changed to align with the wind, see par. 19; see annotated figures below) of at least one of the first rotor 42A and the second rotor 42B to reduce the noise produced by rotation of the first rotor (regarding scenario (2) pertaining to “cruise” discussed above, each rotor causes noise when each rotor is not aligned with the wind, see par. 24 and such noise is reduced by aligning the rotor with the wind) and the second rotor in combination (regarding scenario (1) during VTOL when the motors are electrically powered, the wake vortex of upstream rotor causes noise when it passes by downstream rotor in fig. 11, see pars. 39-40, and such noised is reduced by varying the phase differential angle [Symbol font/0x6A] as discussed above). Thomas does not explicitly disclose the output waveform electrical signature of Thomas including at least one of a phase of a voltage and a current provided to the Thomas at least one propulsion motor; and estimate noise.
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Durkee teaches (see an electric motor (see abstract) and further teaches (see fig. 1) determine a position of a rotor (see abstract) in response to an electrical signature (from current detector 20) of a motor (see abstract), the electrical signature including at least one of a phase of a voltage and a current (current from current detector 20; see par. 25, bottom) provided to the motor 12. It is noted the phrase “at least one of a phase of a voltage and a current” is interpreted as either (1) a phase of voltage or (2) a current. Durkee also teaches the electrical signature also includes a phase of voltage (measurement of back emf by way of voltage detector 22 that measures voltage in one of the three phases of motor 12; such measurement being from a non-energized winding, see par. 34) from the motor and this is similar to the Thomas “output” waveform from the motors.
It would have been obvious to one of ordinary skill in the art before the effective filing date of the current invention to provide Beckman with determine a position of at least one of the first rotor and the second rotor in response to an electrical signature of the at least one propulsion motor, the electrical signature including a current provided to the at least one propulsion motor as taught by Durkee in order to facilitate improvement of quality of controlling motors when there is low rotational velocity (see Durkee pars. 4 and 5).
Beckman teaches (see fig. 1) an electric propulsion unit including electric motors 110,112 coupled to coaxial, see par. 23, fan rotors including a first fan rotor 106 and a second fan rotor 108 and further teaches estimate noise. Beckman teaches the general concept of estimating noise from a rotor. For example, Beckman points out in par. 28 that noise may be measured with an audio sensor 118 or alternatively noise from the rotor may be estimated or predicted using parameters that are a representation of noise:
“The sensor 118 may be configured to sense/detect/measure the noise 120 generated by the lower propeller 106. For example, the sensor 118 may be an audio sensor such as a microphone. However, the sensor 118 may be any type of sensor suitable for directly or indirectly sensing/detecting/ measuring an operational characteristic or parameter associated with the lower propeller 106 that may be interpreted as a representation of the noise 120 generated by the lower propeller 106. For example, the sensor 118 may additionally or alternatively be configured to detect rotational speed of the lower propeller 106, rotational speed of the lower motor 110, etc. AlthoughFIG.1 shows an individual sensor 118, multiple sensors may be used to detect noise generated by an individual propeller, by multiple propellers, in the ambient environment, etc.”
It would have been obvious to one of ordinary skill in the art before the effective filing date of the current invention to provide Thomas in view of Durkee with estimate a noise as taught by Beckman in order to facilitate using the estimate for reasons in addition to or consistent with the “adjusting” discussed above. For example, having a noise estimate can permit evaluation of compliance with surface noise regulations and/or permit noise reduction using the teachings 606 of Beckman in fig. 6 regarding counter-rotation scenario of rotor operation (see par. 13 and pertinent prior art infra describing knowledge of the POSITA in this area). This results in a noise estimate based on rotor velocity and rotor position (Thomas above discloses that phase angle [Symbol font/0x6A] is representative of noise, the phase angle [Symbol font/0x6A] comprising the positions of the first rotor and the second rotor).
Regarding claim 10, Thomas discloses (see figs. 1-3, 6, 7, 9 and 11) a method for reducing noise (see pars. 40-41) of a propulsion system 12 comprising:
determining a position of at least one rotor 42A,42B of a propulsion unit 42A,42B, the at least one rotor being driven about an axis A by at least one propulsion motor 48A,48B in response to an electrical signature (electric signal, i.e. par. 31 “output waveform” from sensors 56A,56B communicates “rotation angle of the first and second motors” to instant controllers, see par. 29 and fig. 7; the relative positions of the instant blades on the rotors is then determined in order to regulate the phase as an operating parameter in order to reduce noise, see pars. 10, 39 and 41, and see figs. 4-5 showing differing phase differential angles [Symbol font/0x6A]) of the at least one propulsion motor 48A,48B;
(evaluate5) (see par. 41: “the computer may adjust the setpoint in an open-loop manner based on one or more sensed or predicted parameter values. Suitable parameter values include rotational velocity of the rotors”; one of ordinary skill would understand that phase [Symbol font/0x6A] and rotational velocity of the rotor correspond with noise; Thomas points out in par. 41 that in order to “reduce the amount of acoustic noise” of the rotors, see par. 18, bottom, the phase differential angle [Symbol font/0x6A] is set by the rotor velocity, the phase differential angle being the difference in “positions” of the two rotors and such phase difference is determined based on sensing the position of each rotor; as general information one of ordinary skill understands when reading Thomas par. 40 that there is a database or table correlating phase differential angle [Symbol font/0x6A] and velocity with a particular noise level and such a table or database is developed by empirical measurements that determines an estimated noise level of each phase angle [Symbol font/0x6A] for particular rotor velocities and this is explained in more detail in pertinent prior art (PPA) infra that explains knowledge of the ordinary worker in the instant art; the PPA explains how the Thomas par. 41 open loop algorithm, or lookup table, is developed and also explains how one of ordinary skill would understand applicant par. 39 database is developed; it is noted that there is no disclosure in applicant specification of a particular algorithm, other than the database, of how the claimed noise estimate is arrived at) a noise generated by the at least one rotor 42A,42B based on the position (this position of each rotor is used to determine the phase differential angle [Symbol font/0x6A] that is used in the claimed “estimate a noise” as explained above) and an operational parameter (rotor velocity; see par. 41) of the at least one rotor;
The setting of the phase differential angle [Symbol font/0x6A] in Thomas par. 41 (i.e. moving the rotors so as to arrive at the phase differential angle [Symbol font/0x6A] setpoint is done to reduce noise) is an evaluation of noise. For example, one phase differential angle [Symbol font/0x6A] setpoint results in a different noise than another phase differential angle [Symbol font/0x6A] setpoint. This is an evaluation of noise because it evaluates the noise of Thomas and because such phase differential angle [Symbol font/0x6A] setpoint is set using the rotor velocity when a direct measurement of noise is not used (see par. 41: “In some examples, the onboard computer may receive input from an onboard microphone and adjust the [phase differential angle [Symbol font/0x6A] ] setpoint in a closed-loop manner so as to reduce the amount noise. In other examples, the computer may adjust the setpoint in an open-loop manner based on … parameter values include rotational velocity of the rotors”).
adjusting one or more operating parameters ((1) phase differential angle, rotational velocity of instant rotors 42A,42B, see pars. 21, 29 and 41, during powered operation of the electric motors for example during VTOL operations using propulsion systems 12 that include the instant motors 48A,48B and rotors 42A,42B; for example, positions of the first 42A and second 42B rotors of Thomas are used reduce noise or acoustic emissions by way of setting the differential phase angle [Symbol font/0x6A] between the positions of the first rotor 42A and the second rotor 42B wherein the differential phase angle [Symbol font/0x6A] is determined by measuring the positions of the first rotor 42A and the second rotor 42B and discussed earlier in this claim analysis (i.e., electric signal from sensors 56A,56B communicates “rotation angle of the first and second motors”, or in other words the position of the rotor, to instant controllers, see par. 29 and fig. 7; the relative positions of the instant blades 44A,44B on the rotors 42A,42B is then determined in order to regulate the phase as an operating parameter in order to reduce noise, see pars. 10, 39 and 41, and see figs. 4-5 showing differing phase differential angles [Symbol font/0x6A]; and (2) alignment of the blades with ambient wind during cruise of the aircraft 10, see pars. 26 and 42, wherein non-alignment of blades causes noise as pointed out in par. 24, such that the instant motors 48A,48B must adjust all the blades to be aligned to the wind to reduce drag on the aircraft; as pointed out in par. 24 whenever the “position” of the rotors 42A,42B are such that blades are not aligned with the wind direction, then this is representative of a noise condition; therefore for example on a day when the wind is aligned with the longitudinal axis of the pylon (see annotated figure above) the position of some blades would represent noise (see par. 24 and see annotated blades above in path of lateral airflow); the motors can change the position of the instant blades to be more aligned with the wind direction (see annotated figures above) based on the position of the lateral blade oriented blade below causing drag (the position being an estimate of noise of Thomas wherein the noise is reduced by the instant aligning, see step 90 in fig. 9); thus during vertical flight of scenario (1), the phase difference [Symbol font/0x6A] between the two rotors are changed, see figs. 4-5, to reduce noise, and during horizontal cruise flight of scenario (2), wherein aircraft propulsion is accomplished by aft engine 20, the phase differential of the instant rotors is zero, see fig. 2, and the position of all the blades together are changed to align with the wind, see par. 19; see annotated figures above) of the at least one rotor 42A,42B using the noise (evaluation) to reduce a noise produced by the propulsion unit (adjusting the phase differential angle reduces noise of wake vortex discussed in pars. 39-40; adjusting the wind alignment also reduces noise, see par. 24). Thomas does not explicitly disclose the output waveform electrical signature of Thomas including at least one of a phase of a voltage and a current provided to the Thomas at least one propulsion motor; and estimating a noise.
Durkee teaches (see an electric motor (see abstract) and further teaches (see fig. 1) determine a position of a rotor (see abstract) in response to an electrical signature (from current detector 20) of a motor (see abstract), the electrical signature including at least one of a phase of a voltage and a current (current from current detector 20; see par. 25, bottom) provided to the motor 12. It is noted the phrase “at least one of a phase of a voltage and a current” is interpreted as either (1) a phase of voltage or (2) a current. Durkee also teaches the electrical signature also includes a phase of voltage (measurement of back emf by way of voltage detector 22 that measures voltage in one of the three phases of motor 12; such measurement being from a non-energized winding, see par. 34) from the motor and this is similar to the Thomas “output” waveform from the motors.
It would have been obvious to one of ordinary skill in the art before the effective filing date of the current invention to provide Beckman with determine a position of at least one of the first rotor and the second rotor in response to an electrical signature of the at least one propulsion motor, the electrical signature including a current provided to the at least one propulsion motor as taught by Durkee in order to facilitate improvement of quality of controlling motors when there is low rotational velocity (see Durkee pars. 4 and 5).
Beckman teaches (see fig. 1) an electric propulsion unit including electric motors 110,112 coupled to coaxial, see par. 23, fan rotors including a first fan rotor 106 and a second fan rotor 108 and further teaches estimating a noise. Beckman teaches the general concept of estimating noise from a rotor. For example, Beckman points out in par. 28 that noise may be measured with an audio sensor 118 or alternatively noise from the rotor may be estimated or predicted using parameters that are a representation of noise:
“The sensor 118 may be configured to sense/detect/measure the noise 120 generated by the lower propeller 106. For example, the sensor 118 may be an audio sensor such as a microphone. However, the sensor 118 may be any type of sensor suitable for directly or indirectly sensing/detecting/ measuring an operational characteristic or parameter associated with the lower propeller 106 that may be interpreted as a representation of the noise 120 generated by the lower propeller 106. For example, the sensor 118 may additionally or alternatively be configured to detect rotational speed of the lower propeller 106, rotational speed of the lower motor 110, etc. AlthoughFIG.1 shows an individual sensor 118, multiple sensors may be used to detect noise generated by an individual propeller, by multiple propellers, in the ambient environment, etc.”
It would have been obvious to one of ordinary skill in the art before the effective filing date of the current invention to provide Thomas in view of Durkee with estimate a noise as taught by Beckman in order to facilitate using the estimate for reasons in addition to or consistent with the “adjusting” discussed above. For example, having a noise estimate can permit evaluation of compliance with surface noise regulations and/or permit noise reduction using the teachings 606 of Beckman in fig. 6 regarding counter-rotation scenario of rotor operation (see par. 13 and pertinent prior art infra describing knowledge of the POSITA in this area). This results in a noise estimate based on rotor velocity and rotor position (Thomas above discloses that phase angle [Symbol font/0x6A] is representative of noise, the phase angle [Symbol font/0x6A] comprising the positions of the first rotor and the second rotor).
Regarding claim 20, Thomas discloses (see figs. 1-3, 6, 7, 9 and 11) an aircraft 10 comprising:
a fuselage 26;
a propulsion unit 12 mounted (via wings 14) to the fuselage, the propulsion unit including a first fan stage including a first rotor 42A and a second fan stage including a second rotor 42B (see blades 44A,44A’,44B,44B’ in fig. 6 regarding fan stages), the first rotor and the second rotor being rotatable about a fan axis A by (via shafts 50A,50B in fig. 6) at least one propulsion motor 48A,48B; and
a controller 24,54A,54B (see fig. 7) configured to:
determine a position of at least one of the first rotor and the second rotor in response to an electrical signature (“output waveforms” from the motors can be the “rotation angle sensors”, see par. 31, communicates “rotation angle of the first and second motors” to instant controllers, see par. 29 and fig. 7 showing example controller 54A and rotation angle sensor 56A; the relative positions of the instant blades on the rotors is then determined in order to regulate the phase as an operating parameter in order to reduce noise, see pars. 10, 39 and 41, and see figs. 4-5 showing differing phase differential angles [Symbol font/0x6A]) of the at least one propulsion motor 48A,48B; and
(evaluate6) (see par. 41: “the computer may adjust the setpoint in an open-loop manner based on one or more sensed or predicted parameter values. Suitable parameter values include rotational velocity of the rotors”; one of ordinary skill would understand that phase [Symbol font/0x6A] and rotational velocity of the rotor correspond with noise; Thomas points out in par. 41 that in order to “reduce the amount of acoustic noise” of the rotors, see par. 18, bottom, the phase differential angle [Symbol font/0x6A] is set by the rotor velocity, the phase differential angle being the difference in “positions” of the two rotors and such phase difference is determined based on sensing the position of each rotor; as general information one of ordinary skill understands when reading Thomas par. 40 that there is a database or table correlating phase differential angle [Symbol font/0x6A] and velocity with a particular noise level and such a table or database is developed by empirical measurements that determines an estimated noise level of each phase angle [Symbol font/0x6A] for particular rotor velocities and this is explained in more detail in pertinent prior art (PPA) infra that explains knowledge of the ordinary worker in the instant art; the PPA explains how the Thomas par. 41 open loop algorithm, or lookup table, is developed and also explains how one of ordinary skill would understand applicant par. 39 database is developed; it is noted that there is no disclosure in applicant specification of a particular algorithm, other than the database, of how the claimed noise estimate is arrived at) a noise generated by at least one of the first rotor 42A and the second rotor 42B based on the position (this position of each rotor is used to determine the phase differential angle [Symbol font/0x6A] that is used in the claimed “estimate a noise” as explained above) and an operational parameter (rotor velocity; see par. 41) of the at least one first rotor or second rotor (this is interpreted as explained in the 112 section above);
The setting of the phase differential angle [Symbol font/0x6A] in Thomas par. 41 (i.e. moving the rotors so as to arrive at the phase differential angle [Symbol font/0x6A] setpoint is done to reduce noise) is an evaluation of noise. For example, one phase differential angle [Symbol font/0x6A] setpoint results in a different noise than another phase differential angle [Symbol font/0x6A] setpoint. This is an evaluation of noise because it evaluates the noise of Thomas and because such phase differential angle [Symbol font/0x6A] setpoint is set using the rotor velocity when a direct measurement of noise is not used (see par. 41: “In some examples, the onboard computer may receive input from an onboard microphone and adjust the [phase differential angle [Symbol font/0x6A] ] setpoint in a closed-loop manner so as to reduce the amount noise. In other examples, the computer may adjust the setpoint in an open-loop manner based on … parameter values include rotational velocity of the rotors”).
in response to the noise, adjust one or more operating parameters ((1)7 phase differential angle, rotational velocity of instant rotors 42A,42B, see pars. 21, 29 and 41, during powered operation of the electric motors for example during VTOL operations using propulsion systems 12 that include the instant motors 48A,48B and rotors 42A,42B; for example, positions of the first 42A and second 42B rotors of Thomas are used reduce noise or acoustic emissions by way of setting the differential phase angle [Symbol font/0x6A] between the positions of the first rotor 42A and the second rotor 42B wherein the differential phase angle [Symbol font/0x6A] is determined by measuring the positions of the first rotor 42A and the second rotor 42B and discussed earlier in this claim analysis (i.e., electric signal from sensors 56A,56B communicates “rotation angle of the first and second motors”, or in other words the position of the rotor, to instant controllers, see par. 29 and fig. 7; the relative positions of the instant blades 44A,44B on the rotors 42A,42B is then determined in order to regulate the phase as an operating parameter in order to reduce noise, see pars. 10, 39 and 41, and see figs. 4-5 showing differing phase differential angles [Symbol font/0x6A]; and (2)8 alignment of the blades with ambient wind during cruise of the aircraft 10, see pars. 26 and 42, wherein non-alignment of blades causes noise as pointed out in par. 24, such that the instant motors 48A,48B must adjust all the blades to be aligned to the wind to reduce drag on the aircraft; as pointed out in par. 24 whenever the “position” of the rotors 42A,42B are such that blades are not aligned with the wind direction, then this is representative of a noise condition; therefore for example on a day when the wind is aligned with the longitudinal axis of the pylon (see annotated figure above) the position of some blades would represent noise (see par. 24 and see annotated blades above in path of lateral airflow); the motors can change the position of the instant blades to be more aligned with the wind direction (see annotated figures above) based on the position of the lateral blade oriented blade above causing drag (the position being an estimate of noise of Thomas wherein the noise is reduced by the instant aligning, see step 90 in fig. 9); thus during vertical flight of scenario (1), the phase difference [Symbol font/0x6A] between the two rotors are changed, see figs. 4-5, to reduce noise, and during horizontal cruise flight of scenario (2), wherein aircraft propulsion is accomplished by aft engine 20, the phase differential of the instant rotors is zero, see fig. 2, and the position of all the blades together are changed to align with the wind, see par. 19; see annotated figures above) of at least one of the first rotor 42A and the second rotor 42B to reduce the noise produced by rotation of the first rotor (regarding scenario (2) pertaining to “cruise” discussed above, each rotor causes noise when each rotor is not aligned with the wind, see par. 24 and such noise is reduced by aligning the rotor with the wind) and the second rotor in combination (regarding scenario (1) during VTOL when the motors are electrically powered, the wake vortex of upstream rotor causes noise when it passes by downstream rotor in fig. 11, see pars. 39-40, and such noised is reduced by varying the phase differential angle [Symbol font/0x6A] as discussed above). Thomas does not explicitly disclose the output waveform electrical signature of Thomas including at least one of a phase of a voltage and a current provided to the Thomas at least one propulsion motor; and estimate noise.
Durkee teaches (see an electric motor (see abstract) and further teaches (see fig. 1) determine a position of a rotor (see abstract) in response to an electrical signature (from current detector 20) of a motor (see abstract), the electrical signature including at least one of a phase of a voltage and a current (current from current detector 20; see par. 25, bottom) provided to the motor 12. It is noted the phrase “at least one of a phase of a voltage and a current” is interpreted as either (1) a phase of voltage or (2) a current. Durkee also teaches the electrical signature also includes a phase of voltage (measurement of back emf by way of voltage detector 22 that measures voltage in one of the three phases of motor 12; such measurement being from a non-energized winding, see par. 34) from the motor and this is similar to the Thomas “output” waveform from the motors.
It would have been obvious to one of ordinary skill in the art before the effective filing date of the current invention to provide Beckman with determine a position of at least one of the first rotor and the second rotor in response to an electrical signature of the at least one propulsion motor, the electrical signature including a current provided to the at least one propulsion motor as taught by Durkee in order to facilitate improvement of quality of controlling motors when there is low rotational velocity (see Durkee pars. 4 and 5).
Beckman teaches (see fig. 1) an electric propulsion unit including electric motors 110,112 coupled to coaxial, see par. 23, fan rotors including a first fan rotor 106 and a second fan rotor 108 and further teaches estimate noise. Beckman teaches the general concept of estimating noise from a rotor. For example, Beckman points out in par. 28 that noise may be measured with an audio sensor 118 or alternatively noise from the rotor may be estimated or predicted using parameters that are a representation of noise:
“The sensor 118 may be configured to sense/detect/measure the noise 120 generated by the lower propeller 106. For example, the sensor 118 may be an audio sensor such as a microphone. However, the sensor 118 may be any type of sensor suitable for directly or indirectly sensing/detecting/ measuring an operational characteristic or parameter associated with the lower propeller 106 that may be interpreted as a representation of the noise 120 generated by the lower propeller 106. For example, the sensor 118 may additionally or alternatively be configured to detect rotational speed of the lower propeller 106, rotational speed of the lower motor 110, etc. AlthoughFIG.1 shows an individual sensor 118, multiple sensors may be used to detect noise generated by an individual propeller, by multiple propellers, in the ambient environment, etc.”
It would have been obvious to one of ordinary skill in the art before the effective filing date of the current invention to provide Thomas in view of Durkee with estimate a noise as taught by Beckman in order to facilitate using the estimate for reasons in addition to or consistent with the “adjusting” discussed above. For example, having a noise estimate can permit evaluation of compliance with surface noise regulations and/or permit noise reduction using the teachings 606 of Beckman in fig. 6 regarding counter-rotation scenario of rotor operation (see par. 13 and pertinent prior art infra describing knowledge of the POSITA in this area). This results in a noise estimate based on rotor velocity and rotor position (Thomas above discloses that phase angle [Symbol font/0x6A] is representative of noise, the phase angle [Symbol font/0x6A] comprising the positions of the first rotor and the second rotor).
Regarding claim 5, Thomas in view of Durkee and Beckman teach the current invention as claimed and discussed above. Thomas discloses (see fig. 7 and par. 29) the controller 54A,54B is configured to determine a relative position of the first rotor and the second rotor in response to the electrical signature (“output waveform” of Thomas par. 31 and teachings of Durkee of the claim 1 analysis above) of the at least one propulsion motor 48A,48B (the relative positions are determined via instant sensors and then the instant controllers adjust the motors to arrive at a differential phase angle [Symbol font/0x6A] that reduces noise).
Regarding claim 6, Thomas in view of Durkee and Beckman teach the current invention as claimed and discussed above. Thomas discloses (see figs. 4 and 7) the one or more operating parameters of at least one of the first rotor and the second rotor is phase (the phase of each rotor is compared to one another to arrive at a phase difference [Symbol font/0x6A] such that noise is reduced; the phase difference is shown in fig. 4, wherein the individual instant phases α and β are discussed in par. 28 having been arrived at from sensors 56A,56B providing par. 31 “output waveform”).
Regarding claim 7, Thomas in view of Durkee and Beckman teach the current invention as claimed and discussed above. Thomas discloses (see fig. 6) the one or more operating parameters of at least one of the first rotor 48A and the second rotor 48B is rotational speed (change of the rotational velocity of the rotors is used to reduce noise; see pars. 29 and 41).
Regarding claim 8, Thomas in view of Durkee and Beckman teach the current invention as claimed and discussed above. Thomas discloses (see fig. 6) the propulsion unit is an electric fan (electric motors 48A,48B drive fan rotors 42A,42B that have blades (44A,44A’,44B,44B’).
Regarding claims 9 and 19, Thomas in view of Durkee and Beckman teach the current invention as claimed and discussed above. Thomas discloses (see figs. 1 and 6) (claims 9 and 19) the propulsion unit 42A,42B is a part of propulsion system 12, see fig. 6, that is mounted to an aircraft 10 (see fig. 1).
Regarding claim 14, Thomas in view of Durkee and Beckman teach the current invention as claimed and discussed above. Thomas discloses (see fig. 6) the at least one rotor 42A,42B further comprises a first rotor 48A and a second rotor 48B and determining the position of the at least one rotor further comprises determining a relative position of the first rotor and the second rotor (electric signature from sensors 56A,56B communicates “rotation angle of the first and second motors” to instant controllers, see par. 29 and fig. 7; the relative positions of the instant blades on the rotors is then determined in order to regulate the phase as an operating parameter in order to reduce noise, see pars. 10, 39 and 41, and see figs. 4-5 showing differing phase differential angles [Symbol font/0x6A]; the relative positions are determined via instant sensors and then the instant controllers adjust the motors to arrive at a differential phase angle [Symbol font/0x6A] that reduces noise).
Regarding claim 15, Thomas in view of Durkee and Beckman teach the current invention as claimed and discussed above. Thomas discloses the adjusting one or more operating parameters ((1) phase differential angle, rotational velocity of instant rotors, see pars. 21, 29 and 41, during powered operation of the electric motors for example during VTOL operations using propulsion systems 12 that include the instant motors and rotors; and (2) alignment of the blades with ambient wind during cruise of the aircraft 10, see pars. 26 and 42, wherein non-alignment of blades causes noise as pointed out in par. 24, such that the instant motors must adjust all the blades to be aligned to the wind to reduce drag on the aircraft; thus during vertical flight, the phase difference [Symbol font/0x6A] between the two rotors are changed, see figs. 4-5, to reduce noise, and during horizontal cruise flight, wherein aircraft propulsion is accomplished by aft engine 20, the phase differential of the instant rotors is zero, see fig. 2, and the position of all the blades together are changed to align with the wind, see par. 19) of at least one rotor is performed to lessen the noise generated by one of the first rotor and the second rotor (adjusting the phase differential angle reduces noise of wake vortex discussed in pars. 39-40; adjusting the wind alignment also reduces noise, see par. 24).
Regarding claim 16, Thomas in view of Durkee and Beckman teach the current invention as claimed and discussed above including the adjusting one or more of at least one rotor (see claim 10 analysis above). Thomas does not explicitly disclose controlling one or more operating parameters of the second rotor to actively cancel the noise generated by the first rotor.
Beckman teaches (see fig. 1) an electric propulsion unit including electric motors 110,112 coupled to coaxial, see par. 23, fan rotors including a first fan rotor 106 and a second fan rotor 108 and further teaches (see par. 15) controlling one or more operating parameters (rotational speed) of the second rotor to actively cancel the noise generated by the first rotor.
It would have been obvious to one of ordinary skill in the art before the effective filing date of the current invention to provide Thomas in view of Durkee and Beckman with controlling one or more operating parameters of the second rotor to actively cancel the noise generated by the first rotor as taught by Beckman in order to facilitate reducing additional noise (see Beckman abstract). This permits noise reduction when the rotors are counter-rotating (see par. 26, bottom) wherein this is known regarding coaxial propellers (see pertinent prior art infra).
Regarding claim 17, Thomas in view of Durkee and Beckman teach the current invention as claimed and discussed above. Thomas discloses the adjusting one or more operating parameters of at least one rotor includes adjusting a phase of the at least one rotor (the phase of each rotor is compared to one another to arrive at a phase difference [Symbol font/0x6A] such that noise is reduced; the phase difference is shown in fig. 4, wherein the individual instant phases α and β are discussed in par. 28 having been arrived at from sensors 56A,56B; the phase difference, or in other words the phase differential angle [Symbol font/0x6A], is adjusted to reduce noise, see par. 41).
Regarding claim 18, Thomas in view of Durkee and Beckman teach the current invention as claimed and discussed above. Thomas discloses the adjusting one or more operating parameters of at least one rotor 48A,48B includes adjusting a rotational speed of the at least one rotor (change of the rotational velocity of the rotors is used to reduce noise; see pars. 29 and 41).
Response to Arguments
Applicant's arguments filed 12/30/2025 have been fully considered but they are not persuasive. Applicant argues that the cited prior art Thomas and/or Beckman do not teach estimating a noise generated by the rotor based on the position and an operational parameter of the rotor. In response Thomas discloses an evaluation of noise that is similar to an estimate but such evaluation does not reach an approximation of noise and this approximation is taught by Beckman in 103 section above. Applicant specification discusses “estimate” regarding an approximation of noise (par. 39) and states the “the operational or noise information output from the noise estimation module 104” (par. 40) such noise information similar to what Thomas does in par. 41 when direct noise measurement is not used.
Beckman teaches (see fig. 1) an electric propulsion unit including electric motors 110,112 coupled to coaxial, see par. 23, fan rotors including a first fan rotor 106 and a second fan rotor 108 and further teaches estimate noise. Beckman teaches the general concept of estimating noise from a rotor. For example, Beckman points out in par. 28 that noise may be measured with an audio sensor 118 or alternatively noise from the rotor may be estimated or predicted using parameters that are a representation of noise:
“The sensor 118 may be configured to sense/detect/measure the noise 120 generated by the lower propeller 106. For example, the sensor 118 may be an audio sensor such as a microphone. However, the sensor 118 may be any type of sensor suitable for directly or indirectly sensing/detecting/ measuring an operational characteristic or parameter associated with the lower propeller 106 that may be interpreted as a representation of the noise 120 generated by the lower propeller 106. For example, the sensor 118 may additionally or alternatively be configured to detect rotational speed of the lower propeller 106, rotational speed of the lower motor 110, etc. AlthoughFIG.1 shows an individual sensor 118, multiple sensors may be used to detect noise generated by an individual propeller, by multiple propellers, in the ambient environment, etc.”
Thus Beckman teaches estimating noise (in lieu of directly measuring noise with a microphone) by using parameters that represent noise such as rotor velocity (and Thomas disclosed rotor position is representative noise; for example, Thomas points out that “The rotation angle sensors may be … acoustic” in par. 31 and “the differential phase angle desired to reduce acoustic emission” in par. 39). Thus Thomas and Beckman teach together approximating or estimating noise based on rotor velocity and rotor position. It is noted that there is no disclosure in applicant specification of a particular algorithm, other than the database in par. 39, of how the claimed noise estimate is arrived at.
Applicant’s arguments with respect to the recitation regarding the electronic signature including one or more of a phase of the voltage and a current provided to the motor have been considered but are moot because the new ground of rejection does not rely on any reference applied in the prior rejection of record for any teaching or matter specifically challenged in the argument.
Pertinent Prior Art
The prior art made of record and not relied upon is considered pertinent to applicant's disclosure:
US 5027277: regarding “the desired phase shift between … propellers … [the] phase shift is determined empirically by measuring vibration and noise at different phase settings in an aircraft. Once the phase shift is determined at which minimum noise and vibration are experienced, the desired shift between the … [propellers] is known, and is commanded” in flight (col. 3, ll. 20-30).
US 20170274984:
“For example, … at a … rotational speed of the propulsion mechanism, the rotational phase alignment of the propellers 413, 416 may be adjusted” (par. 52).
“The propellers 216-1B, 216-1C, even though coupled to different shafts are coaxially aligned. In addition,… rather than counter-rotating the propellers 216-1B, 216-1C, during some modes of operation the propellers may be in rotational phase alignment and rotated in the same direction (co-rotated)” (par. 38).
US 20200335077: Sensor 140 may alternatively be configured to provide information regarding a rotational speed of propeller 110 (e.g., revolutions per minute, RPM). … Based on the information from sensor 140, controller 150 may be operable to determine properties of sound being emitted from the propeller 110 and/or acoustic resonator 120. For example, controller 150 may use a look-up table with a plurality of acoustic spectra measured under similar propeller speed conditions (par. 39).
NPL “"On the noise generation mechanisms of overlapping propellers": propeller boom noise.
electrical signature: US 20090261775 20250350216 20250388331
Conclusion
Any inquiry concerning this communication or earlier communications from the examiner should be directed to MARC J AMAR whose telephone number is (571)272-9948. The examiner can normally be reached M-F 9:00-6:00.
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/MARC AMAR/Examiner, Art Unit 3741 /DEVON C KRAMER/Supervisory Patent Examiner, Art Unit 3741
1 See definition of “respectively” from Merriam-Webster online: “in the order given”; My cousin and I were respectively 12 and 16 years old.
2 This term is used for readability because Thomas discloses an evaluation of noise that is similar to an estimate but such evaluation does not reach an approximation of noise and this approximation is taught by Beckman in this claim analysis. Applicant specification discusses “estimate” regarding an approximation of noise (par. 39) and states the “the operational or noise information output from the noise estimation module 104” (par. 40) such noise information similar to what Thomas does in par. 41 when direct noise measurement is not used.
3 During VTOL when the motors are driving the propellers.
4 During cruise when the motors are not driving the propellers except for aligning propellers with wind to reduce noise.
5 This term is used for readability because Thomas discloses an evaluation of noise that is similar to an estimate but such evaluation does not reach an approximation of noise and this approximation is taught by Beckman in this claim analysis. Applicant specification discusses “estimate” regarding an approximation of noise (par. 39) and states the “the operational or noise information output from the noise estimation module 104” (par. 40) such noise information similar to what Thomas does in par. 41 when direct noise measurement is not used.
6 This term is used for readability because Thomas discloses an evaluation of noise that is similar to an estimate but such evaluation does not reach an approximation of noise and this approximation is taught by Beckman in this claim analysis. Applicant specification discusses “estimate” regarding an approximation of noise (par. 39) and states the “the operational or noise information output from the noise estimation module 104” (par. 40) such noise information similar to what Thomas does in par. 41 when direct noise measurement is not used.
7 During VTOL when the motors are driving the propellers.
8 During cruise when the motors are not driving the propellers except for aligning propellers with wind to reduce noise.