# US 2019/0171233 A1 · Methods and apparatus to perform observer-based control of a vehicle > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2019/0171233 A1 - Document ID: US20190171233A1 - Status: Published application - Kind: A1 - Application number: 16/271,106 - Filed: 2019-02-08 - Published: 2019-06-06 - Earliest claimed: 2017-03-21 - Assignees: The Boeing Company - Applicants: The Boeing Company - Inventors: Eugene Lavretsky; Kevin Andrew Wise - Web page: https://patentgrep.com/patent/US20190171233A1 ## CPC - G05D 1/0808: {specially adapted for aircraft} - G05B 6/02: electric - G05D 1/0825: {using mathematical models} - G05D 1/0875: {specially adapted to water vehicles} - G05D 1/0891: {specially adapted for land vehicles} - G05D: SYSTEMS FOR CONTROLLING OR REGULATING NON-ELECTRIC VARIABLES - G05B: CONTROL OR REGULATING SYSTEMS IN GENERAL; FUNCTIONAL ELEMENTS OF SUCH SYSTEMS; MONITORING OR TESTING ARRANGEMENTS FOR SUCH SYSTEMS OR ELEMENTS (systems for controlling or regulating non-electric variables G05D; systems for regulating electric or magnetic variables G05F; control devices or systems insofar as characterised by mechanical features only G05G) ## Abstract Methods, apparatus, and articles of manufacture to perform observer based control of a vehicle are disclosed. An example apparatus includes an error module to calculate a difference between a first state of a vehicle and a second state of the vehicle, the second state based on a measurement from a sensor, an observer module to determine a third state of the vehicle based on the difference, a baseline control module to generate a first command based on the third state, and a vehicle module to execute the first command to control the vehicle. ## Claims ### Claim 1 An apparatus comprising: an observer module to determine a first state of a vehicle based on a difference between a second state of the vehicle and a third state of the vehicle, the second state based on a bounded command, the third state based on a measurement from a sensor, the observer module is to determine the first state by: determining a sum based on applying an observer error feedback gain and a gain command value to the second state, the observer error feedback gain based on an output observation error and a measured plant output, the output observation error based on an identity matrix, the measured plant output based on the sensor; and executing a transfer function using the sum to generate the first state; a baseline control module to generate a first command based on the first state; and a vehicle module to execute the first command to control the vehicle by moving a control surface from a first position to a second position. ### Claim 2 (depends on 1) The apparatus of claim 1, wherein the identity matrix is a first identity matrix and the transfer function includes a first matrix and a second matrix, the first matrix corresponding to a second identity matrix different from the first identity matrix, the second matrix corresponding to a state matrix of an observer model. ### Claim 3 (depends on 1) The apparatus of claim 1, wherein the observer module is to estimate the second state by performing a squaring-up modification on an input matrix to determine a pseudo-input matrix, wherein the pseudo-input matrix includes a number of inputs equal to a number of outputs in an output matrix. ### Claim 4 (depends on 3) The apparatus of claim 3, wherein the observer module is to estimate the second state by calculating one or more transmission zeros in an open left half of a complex plane based on the pseudo-input matrix. ### Claim 5 (depends on 1) The apparatus of claim 1, wherein determining the second state includes calculating at least one of an angle of attack parameter or a sideslip parameter based on the measurement from the sensor, the sensor including at least one of an acceleration sensor, a gyro sensor, or an angular rate sensor. ### Claim 6 (depends on 1) The apparatus of claim 1, further including an adaptive control module to generate a control law to determine an adaptive control command based on the first state. ### Claim 7 (depends on 1) The apparatus of claim 1, wherein the first command is based on a control input, the observer module is to generate the control input by applying a constant Linear Quadratic Regulator baseline control gain to the first state. ### Claim 8 A non-transitory computer readable medium comprising instructions which, when executed, cause a machine to at least: determine a first state of a vehicle based on a difference between a second state of the vehicle and a third state of the vehicle, the second state based on a bounded command, the third state based on a measurement from a sensor, the machine is to determine the first state by: determining a sum based on applying an observer error feedback gain and a gain command value to the second state, the observer error feedback gain based on an output observation error and a measured plant output, the output observation error based on an identity matrix, the measured plant output based on the sensor; and executing a transfer function using the sum to generate the first state; generate a first command based on the first state; and execute the first command to control the vehicle by moving a control surface from a first position to a second position. ### Claim 9 (depends on 8) The non-transitory computer readable medium of claim 8, wherein the identity matrix is a first identity matrix and the transfer function includes a first matrix and a second matrix, the first matrix corresponding to a second identity matrix different from the first identity matrix, the second matrix corresponding to a state matrix of an observer model. ### Claim 10 (depends on 8) The non-transitory computer readable medium of claim 8, wherein the instructions, when executed, cause the machine to estimate the second state by performing a squaring-up modification on an input matrix to determine a pseudo-input matrix, wherein the pseudo-input matrix includes a number of inputs equal to a number of outputs in an output matrix. ### Claim 11 (depends on 10) The non-transitory computer readable medium of claim 10, wherein the instructions, when executed, cause the machine to estimate the second state by calculating one or more transmission zeros in an open left half of a complex plane based on the pseudo-input matrix. ### Claim 12 (depends on 8) The non-transitory computer readable medium of claim 8, wherein the instructions, when executed, cause the machine to determine the second state by calculating at least one of an angle of attack parameter or a sideslip parameter based on the measurement from the sensor, the sensor including at least one of an acceleration sensor, a gyro sensor, or an angular rate sensor. ### Claim 13 (depends on 8) The non-transitory computer readable medium of claim 8, wherein the instructions, when executed, cause the machine to generate a control law to determine an adaptive control command based on the first state. ### Claim 14 (depends on 8) The non-transitory computer readable medium of claim 8, wherein the first command is based on a control input, and the instructions, when executed, cause the machine to generate the control input by applying a constant Linear Quadratic Regulator baseline control gain to the first state. ### Claim 15 A method comprising: determining a first state of a vehicle based on a difference between a second state of the vehicle and a third state of the vehicle, the second state based on a bounded command, the third state based on a measurement from a sensor, the determining of the first state including: determining a sum based on applying an observer error feedback gain and a gain command value to the second state, the observer error feedback gain based on an output observation error and a measured plant output, the output observation error based on an identity matrix, the measured plant output based on the sensor; and executing a transfer function using the sum to generate the first state; generating a first command based on the first state; and executing the first command to control the vehicle by moving a control surface from a first position to a second position. ### Claim 16 (depends on 15) The method of claim 15, wherein the identity matrix is a first identity matrix and the transfer function includes a first matrix and a second matrix, the first matrix corresponding to a second identity matrix different from the first identity matrix, the second matrix corresponding to a state matrix of an observer model. ### Claim 17 (depends on 15) The method of claim 15, wherein estimating the second state includes performing a squaring-up modification on an input matrix to determine a pseudo-input matrix, wherein the pseudo-input matrix includes a number of inputs equal to a number of outputs in an output matrix. ### Claim 18 (depends on 17) The method of claim 17, wherein estimating the second state includes calculating one or more transmission zeros in an open left half of a complex plane based on the pseudo-input matrix. ### Claim 19 (depends on 15) The method of claim 15, wherein determining the second state includes calculating at least one of an angle of attack parameter or a sideslip parameter based on the measurement from the sensor, the sensor including at least one of an acceleration sensor, a gyro sensor, or an angular rate sensor. ### Claim 20 (depends on 15) The method of claim 15, further including generating a control law to determine an adaptive control command based on the first state. ### Claim 21 (depends on 15) The method of claim 15, wherein the first command is based on a control input, and further including generating the control input by applying a constant Linear Quadratic Regulator baseline control gain to the first state.