Abstract: A vehicle diagnosis system has: a diagnosis unit that diagnoses an abnormality of a part separating the inside and the outside of a vehicle cabin in a vehicle; an alarm and a horn located outside the vehicle cabin; and a microphone located inside the vehicle cabin. The diagnosis unit executes an acquisition process of, when the alarm or the horn emits a sound, acquiring detected sound data about the sound as detected by the microphone, and a determination process of determining whether the part has an abnormality by comparing the detected sound data with predetermined reference sound data.

Abstract: This disclosure provides a means to implement an autonomous guidance and flight control system on a partial authority aircraft. One embodiment of the disclosure includes receiving a control command result, filtering the control command result into a low frequency component and a high frequency component, directing the low frequency component to at least one trim servomechanism and directing the high frequency component to at least one stability augmentation stabilizer servomechanism, linking outputs from the trim servomechanism and the stability augmentation stabilizer servomechanism for actuating a pilot control configured to control rotors, and actuating at least one rotor. The low frequency component includes frequencies below a break frequency and the high frequency component includes frequencies above the break frequency. The break frequency is established by rate and position of the at least one servomechanism.

Abstract: A multi-rotor aircraft includes a fuselage, a propulsion engine coupled to the fuselage that generates thrust to propel the aircraft along a first vector during forward flight, and rotors coupled to the fuselage, each rotor comprising blades, each rotor coupled to a motor, and each motor configured to supply power to and draw power from the coupled rotor. The aircraft includes a flight control system configured to control the motors coupled to the rotors in a power managed regime in which a net electrical power, consisting of a sum of the power being supplied to or drawn from each rotor by its motor, is maintained within a range determined by a feedback control system of the flight control system. The flight control system can also be leveraged to adjust rotor control inputs to modify at least one of thrust, roll, pitch, or yaw of the multi-rotor aircraft.

Abstract: The present invention relates to the field of unmanned aerial vehicle safety protection technologies, and in particular, to an unmanned aerial vehicle safety protection method and apparatus and an unmanned aerial vehicle. The method includes: obtaining ultrasonic information and a flight status of an unmanned aerial vehicle, where the flight status includes a normal flight state and a descending state; and performing safety protection on the unmanned aerial vehicle according to the ultrasonic information and the flight status. The implementation can reduce an occurrence probability that an unmanned aerial vehicle crashes at a high altitude when ultrasound encounters abnormalities to get out of control at the high altitude and fail to descend, rise, move to the left or move to the right and land without slowing down to violently hit the ground, so that the safety of the unmanned aerial vehicle is enhanced, and user experience is improved.

Abstract: Embodiments of the present invention are an unmanned aerial vehicle (UAV) severe low-power protection method and a UAV. The method includes: first acquiring ground environment information when the UAV is in a severe low-power protection state, and then obtaining landing safety judgment information according to the ground environment information, and further controlling a flight state of the UAV according to the landing safety judgment information to realize a safe landing of the UAV. The foregoing method reduces the probability of explosion of the UAV, avoids injury accidents, and improves flight safety when the UAV is in a severe low-power state.

Abstract: Data characterizing a fuel storage facility can be received from one or more of a plurality of sensors disposed in the fuel storage facility. A fuel leak prediction for the fuel storage facility can be determined by a server, based on the received data, and further based on at least one predictive model that predicts whether a fuel leak exists in the fuel storage facility. The fuel leak prediction can be provided by the server. Related apparatus, systems, methods, techniques, and articles are also described.

Abstract: A system for monitoring the landing zone of an electric aircraft, the system including an electric aircraft wherein the electric aircraft includes at least a sensor configured to measure a plurality of data of regarding a first potential landing zone and transmit the plurality of data to at least a flight controller. The flight controller is designed and configured to receive the plurality of data from at least a sensor, determine a landing safety datum as a function of the plurality of data and at least a safety parameter range, and transmit the landing safety datum to an output device. The output device is designed and configured to receive the plurality of data from the flight controller, and display, to the pilot, the landing safety datum and a locator component designed and configured to capture a second potential landing zone that is distinct from the first potential landing zone.

Abstract: A method of and a system for detecting a fuel leak in an aircraft, the aircraft comprising a first engine and a second engine. The method comprises upon determining that the aircraft has reached a first mode of operation: acquiring a first baseline fuel flow of the first engine; acquiring a second baseline fuel flow of the second engine. The method further comprises monitoring a first current fuel flow measured at the first engine and a second current fuel flow measured at the second engine; and triggering a fuel leak detection based on an analysis of the first baseline fuel flow, the first current fuel flow, the second baseline fuel flow and the second current fuel flow.

Abstract: A cloud-based trajectory map generation method, device, apparatus and application. The method includes: acquiring first trajectory map data and second trajectory map data; performing a map-initializing treatment to align the two trajectory map data to obtain an initial value of a transformation relationship therebetween; interpolating the two trajectory map data to obtain corresponding data at preset interpolation points thereto; determining a residual equation based on the corresponding data at the preset interpolation points and the initial value of the transformation relationship to obtain an optimal solution of the transformation relationship based thereon; and generating a trajectory map based on the optimal solution of the transformation relationship.

Abstract: An electronic device includes a receiver, a processor, and a communication unit. Via the communication unit from an external device, the processor receives altitude information on each of altitudes obtained at intervals of a first period, at intervals of a second period that is longer than the first period, and individually receives altitude information on an altitude obtained not at intervals of the first period. In response to receiving the altitude obtained not at intervals of the first period, the processor performs positioning at the receiving timing. Based on obtainment timings of the altitudes received at intervals of the second period and an obtainment timing of the altitude received individually, the processor correlates the altitudes received at intervals of the second period and the altitude received individually with positioning results of the positioning such that the obtainment timings correspond to positioning timings of the positioning results.

Abstract: A virtual reality apparatus includes a head mountable display (HMD); a detector to detect a deviation of a current orientation of the HMD from a base orientation of the HMD; and a generator to generate content for presentation to the wearer of the HMD to prompt the wearer of the HMD to turn his head so as to change the orientation of the HMD towards the base orientation.

Abstract: A system and method of shifting a premature descent protection envelope for an aircraft has been developed. First, a premature descent protection envelope (PDP) is determined including a first boundary at a first distance from the runway. Next, a nominal approach path is determined for approaching the runway and an approach path angle. Also, a flight path angle of the aircraft is determined. The first boundary is shifted in an upward direction from the runway in response to the aircraft being below the nominal approach path, and the flight path angle being greater than the nominal approach path angle.

Abstract: A method may include the following steps: determining, based on timing measurements between a first digital radio communication device (DRCD) node and at least a second DRCD node, a distance between the first DRCD disposed on a tanker and the second DRCD disposed about a loading/unloading facility; and facilitating, in response to determining a position based on the timing measurements, fluid payload loading/unloading of the tanker at the loading/unloading facility.

Abstract: UAV airways system generally are disclosed. Such UAV airway systems may comprise UAV cargo transportation systems and UAV surveillance and monitoring systems. Such systems preferably overlay and are commensurate with a system of high-voltage power transmission lines of high-voltage transmission system, and electric field actuated (EFA) generators preferably are utilized in UAVs that travel along the transmission lines, in UAV charging stations located along the transmission lines, or in both. Each EFA generator represents a power supply and comprises first and second electrodes separated and electrically insulated from each other for enabling a differential in voltage at the first and second electrodes resulting from a differential in electric field strength experienced by the first and second electrodes arising from the power transmission lines of the high-voltage transmission system.

Abstract: Methods and apparatus are provided for displaying the operational parameters of a radio system located onboard an aircraft. The apparatus comprises a permanent radio display bar that shows an active radio frequency in use by the radio system and a variable radio display pad. The variable radio display pad shows multiple historical past radio frequencies previously used by the radio system and multiple predicted future radio frequencies for use along a flight plan of the aircraft. It includes a change command that allows a crew member to manually change the active radio frequency in the permanent radio display bar.

Abstract: Systems and methods for determining object location may include a memory and a processor. The processor may be configured to collect seismic data and geophysical data to determine object location. The processor may be configured to determine one or more seismic attributes associated with a plurality types of noises based on the seismic data and the geophysical data using one or more machine learning algorithms. The processor may be configured to eliminate unwanted noises from noise classifications based on the one or more seismic attributes. The processor may be configured to predict the object location by comparing time and velocity data of the object with recorded timing and velocity data. The processor may be configured to validate the object location by comparing the determined noise with image data. The systems and methods may be used in, for example, detecting missing planes such as Malaysian Airlines Flight 370.

Abstract: Methods and systems are provided for operating a vehicle during operating conditions where wheel slip may occur. In one example, a torque vectoring electric machine torque output is adjusted to direct propulsion torque from one wheel to a different wheel. Additionally, the propulsive torque is adjusted responsive to a driver demand wheel torque.

Abstract: A method for providing aircraft descent data and approach data onboard an aircraft is provided. The method determines a safe descent area bounded by an outer boundary region, by a processor communicatively coupled to a system memory element, based on an optimum glideslope angle, variable glideslope data, and a continuously monitored boundary exceedance condition; and presents graphical elements associated with the safe descent area, the optimum glideslope angle, and the outer boundary region, by a display device communicatively coupled to the processor.

Abstract: An airborne platform includes an avionics controller circuit. The avionics controller circuit is configured to receive an ownship orientation from a sensor configured to detect the ownship orientation. The avionics controller circuit is configured to determine an orientation parameter based on the ownship orientation. The avionics controller circuit is configured to compare the orientation parameter to an orientation threshold. The avionics controller circuit is configured to determine the ownship to be in a wake vortex condition based on at least one wake vortex criteria, the at least one wake vortex criteria including the orientation parameter being greater than the orientation threshold for more than a predetermined period of time.

Abstract: A system for collecting information regarding a flight restriction region includes one or more processors and a non-transitory computer readable storage medium storing instructions that, when executed by the one or more processors, cause the one or more processors to individually or collectively receive, from a user input device, an input designating one or more parameters of the flight restriction region. The one or more parameters include a location of the flight restriction region. The instructions further cause the one or more processors to determine a space for the flight restriction region based on the one or more parameters.

Abstract: A wireless power transfer system includes a power transmitter (101) arranged to provide a power transfer to a power receiver (105) via a wireless inductive power signal. A parasitic power loss detector (207) is arranged to detect a parasitic power loss for the power transfer, and a user indicator (209) is arranged to initialize a user alert in response to the detection of the parasitic power loss. The system comprises an input (211) for receiving user inputs; and a controller (213) which is arranged to initiate an adaptation of a parasitic power loss detection operation performed by the parasitic power loss detector (207) to detect parasitic power losses if a user input meeting a criterion is not received. Each of the individual features may be implemented in the power transmitter (101), the power receiver (105), or may e.g. be distributed between these. The approach may allow improved foreign object detection in a wireless power transfer system.

Abstract: In various embodiments, a safety system for an unmanned aerial vehicles (UAV) enable the safe operation of the UAV, alone or with other UAVs, within an airspace by initiating various actions based on the position of the UAV and/or one or more of the other UAVs relative to one or more flight zones and/or relative to other aircraft in the airspace.

Abstract: Systems and methods for an aircraft emergency and park brake system are disclosed. The emergency and park brake system may comprise an emergency and park brake controller. The emergency and park brake controller may be configured to receive brake signals from mechanical and electrical inputs, generate a braking command comprising data from the brake signal, and transmit the braking command to control braking force. The emergency and park brake controller may receive brake signals from multiple locations including from the aircraft and from a remote location.

Abstract: A system for documenting the state of a component, for example a component present on board a transport device; the use of such a system in a transport device; a transport device having such a system; an associated method for documenting the state of a component; and a computer program for executing the method. The transport device may be an aircraft. The system comprises a central logbook equipment and at least one mobile recording device, the mobile recording device comprising a recording unit for recording items of multimedia information relating to the state of the component, and a transmitting unit for transmitting the recorded items of multimedia information to the central logbook equipment. The central logbook equipment is configured to generate a multimedia logbook entry on the basis of the transmitted items of multimedia information, and to store the generated multimedia logbook entry.

Abstract: An approach for triggering the conveyance of guidance information based on the current line-of-sight of the user is described. A guidance platform processes and/or facilitates a processing of sensor information associated with a device, a user of the device, or a combination thereof to determine (a) line-of-sight information to at least one navigation element, (b) one or more user behavior patterns, or (c) a combination thereof. The guidance platform then determines a timing, a frequency, or a combination thereof of at least one presentation of guidance information based, at least in part, on the line-of-sight information.

Abstract: A method and apparatus for determining routes vehicles (4, 6), the method comprising: measuring positions of a first vehicle and a second vehicle (6); providing a specification of a region (12) having a fixed position in relation to the first vehicle (4); using the measurements and the region specification, determining a first route for the first vehicle (4) and a second route for the second vehicle (6). Determining the routes comprises: constructing a graph (34) within a joint state space (X) of the vehicles (4, 6); identifying, within the graph (34), a path from a first vertex to a second vertex, the first vertex corresponding to the measured positions of the vehicles (4, 6), and the second vertex corresponding to the second vehicle (6) being at least partially located within the region (12); and, using the identified path, determining the first and second routes.

Abstract: A system and method are provided for integrating live flight following information provided as Trusted Automatic Dependent Surveillance-Broadcast (ADS-B) data with stored planned flight and other information, and for, in part, comparatively analyzing the data/information to generate automated alerts to one or more end-users when an aircraft is determined to deviate from a planned flight route by a predetermined degree, as specified by adjustable set parameters. Broadcast ADS-B data transmitted by participating aircraft is collected and communicated via a secure, trusted and dependable worldwide network for analysis in a centralized location. The analysis involves, in part, comparing the ADS-B data to other information provided to, or collected by, the centralized location from multiple sources regarding planned routes of flight for participating aircraft and other available information relevant to aircraft operations in particular geographic locations.

Abstract: A mobile device includes an inertial navigation system (INS) to measure inertial quantities associated with movement of the device, and estimate a kinematic state associated with the movement based on the measured inertial quantities. The device includes a light receiver to record light beams originating from lights at respective image positions in a sequence of images. The device photogrammetrically determines its position relative to the originating lights based on predetermined real-world positions and corresponding image positions of the lights. The device corrects the estimated kinematic state based on the photogrammetrically determined position, to produce a corrected estimated kinematic state.

Abstract: Embodiments of a flight deck display system deployed onboard a rotary wing aircraft are provided, as are embodiments of a method carried-out by a flight deck display system. In one embodiment, the flight deck display system includes a controller operably coupled to a cockpit display device. The controller is configured to: (i) generate a Primary Flight Display (PFD) on the cockpit display device including a vertical speed indicator; (ii) establish a first vertical speed alert threshold; (iii) compare the first vertical speed alert threshold to a current vertical speed of the rotary wing aircraft; and (iv) if the current vertical speed of the rotary wing aircraft exceeds the first vertical speed alert threshold, produce a first vertical speed alert on the PFD by altering the appearance of the vertical speed indicator in a first predetermined manner.

Abstract: This method for determining an obstacle avoidance guidance law for an aircraft is implemented by a system for determining said guidance law. The aircraft comprises a collision avoidance system adapted to detect a collision risk with the obstacle and said determination system. This method comprises determining one or more set points from among flight path angle and speed set points, at least one set point depending on at least one vertical speed limit value, at least one set point comprising a vertical component in a vertical direction, each limit value being provided by the collision avoidance system following the detection of a collision risk with the obstacle; and computing the avoidance guidance law as a function of the determined set points. During the determination step, at least one determined set point comprises a longitudinal component in a longitudinal direction perpendicular to the vertical direction.

Abstract: Methods, systems, and computer readable media are disclosed for troubleshooting and repairing an aircraft system failure during abnormal situations of an aircraft's operation. One aspect of a method for implementing the subject matter described herein includes at least one interactive interface configured for troubleshooting and repairing an aircraft system failure. The method also includes displaying at least one or more graphic object representing at least one or more aircraft system and configured for receiving interaction from a user, displaying at least one or more energy flow icon representing the direction of circulation of an energy flow, and displaying at least one or more macro action icon configured for performing an automated action sequence configured for troubleshooting and repairing the system failure.

Abstract: The use of dynamic collision avoidance parameters in connection with automatic dependent surveillance, broadcast, as well as for other purposes in systems and methods may assist collision avoidance and/or advisory systems in properly identifying intruders for reporting to pilots. For example, a method can include monitoring for a triggering event with respect to at least one of geographic coordinates and a flight path of an aircraft. The method can also include detecting the triggering event. The method can further include altering at least one characteristic of at least one of a traffic alerting system and an advisory system based on detecting the triggering event.

Abstract: Systems and methods that alert the pilot of the unusual negative pitch attitude. Additionally, the system can bias a “sink rate” envelope toward a more sensitive direction, such that the pilot can be alerted while (or before) a large sink rate is built up during an unusual negative pitch attitude condition.

Abstract: Novel and non-trivial systems and methods for generating and providing alerts in a terrain awareness and warning system (“TAWS”) are disclosed. The systems could be comprised of a navigation system, an airport-related database, a terrain database, a terrain alert processor, and crew alerting system. A phase of flight and flight attitude parameter may be determined based on the location to the nearest airport or runway environment, and a terrain clearance altitude associated with the phase of flight and flight attitude parameter may be added to the highest elevation of a terrain cell over which the aircraft is projected to operate to determine a minimum operating altitude of the terrain cell. If the aircraft altitude is less than any value of minimum operating altitude along the projected flight path, an alert signal is generated.

Abstract: Systems and methods for providing runway entry awareness and alerting. An exemplary system includes a processing device that determines pilot intent based on one of a manual runway selection, automatic runway selection, aircraft information received from one or more sensors or received clearance information; receives at least one of aircraft position or motion information; determines if a no access condition exists based on the received information, the stored airport information and the determined pilot intent; and generates at least one of a hold-short gate still image or animation, if the no access condition exists.

Abstract: A method of determining a turbulent condition in an aircraft with a handheld device where the handheld device has at least one of a gyroscope, seismometer, and an accelerometer where the method includes receiving an output from the at least one of the gyroscope, seismometer, and accelerometer while the handheld device is located within the aircraft and providing an indication of a turbulent condition.

Abstract: A power safety system is configured to provide power information in an aircraft. The power safety system includes a power safety instrument having a power required indicator and a power available indicator, each being located on a display. A position of the power required indicator and the power available indicator represent the power available and power required to perform a hover flight maneuver. The power safety system may be operated in a flight planning mode or in a current flight mode. The power safety system uses at least one sensor to measure variables having an effect on the power required and the power available.

Abstract: A taxiway approach advisory system. The system may include a computer-readable memory containing runway information and a processor in data communication with the memory. The processor may include a component for ascertaining the altitude of an aircraft, a component for ascertaining the location of the aircraft, a component for accessing runway information from the memory and determining if the aircraft is within a pre-determined runway envelope based on the altitude and location, and a component for issuing an indication if the aircraft is not within the pre-determined runway envelope.

Abstract: A method of displaying navigation limits for a planned travel route of a vehicle is presented here. The method calculates estimated navigation limits for the vehicle using an onboard subsystem of the vehicle, where the estimated navigation limits represent self-assessed navigation accuracy of the vehicle relative to the planned travel route. Contracted navigation limits are acquired for the vehicle, where the contracted navigation limits represent specified navigation accuracy of the vehicle, relative to the planned travel route, as mandated by a third party navigation controller. A navigation display is rendered on an onboard display element such that it includes graphical representations of the planned travel route, at least one of the estimated navigation limits, and at least one of the contracted navigation limits.

Abstract: The present invention relates to a method for detecting the performance of the aircraft comprising: collecting data reflecting operation status of the aircraft; generating the customized message based on the collected data, wherein, the customized message is configured to include one or more main parameters related to the operation status of the aircraft; storing or transmitting the customized message; and detecting the performance of the aircraft based on the customized message.

Abstract: A terrain warning system includes an indicator to inform a pilot of a proposed degree of flight parameters for safely clearing terrain. An aural message may identify a vertical speed that may be used to safely traverse terrain to the pilot. A visual indicator on a display informs the pilot of a vertical speed or climb angle to traverse terrain. The display may be a vertical speed indicator also capable of displaying traffic advisories.

Abstract: A method for detecting piloting conflicts between the crew and the autopilot of an aircraft. According to the method, an automatic trajectory is programmed by checking whether the actual values of navigation parameters converge on said corresponding desired values within a predetermined convergence period; in the case where at least one of the actual values does not converge, within the convergence period, on the corresponding desired value, a predictive calculation is carried out, at consecutive future moments, of the value of at least one particular parameter selected amongst the navigation parameters; and in the case where the predicted value of the particular parameter is higher than a corresponding predefined threshold, an alarm is emitted for the crew of the aircraft to notify them about a piloting conflict being able to jeopardize the flight safety of the aircraft. A device for implementing the method. An aircraft including the device.

Abstract: Systems and methods for adjusting target approach speed for use in a “Too Fast” approach to landing condition. An exemplary system stores predefined maximum wind setting and a predefined reference speed and a pilot set bug speed value. A processing device sets a target speed equal to the bug speed, if the bug speed is less than the reference speed plus a value associated with a predefined maximum wind setting, and sets the target speed equal to the reference speed plus the max wind added value, if the manual bug speed is not less than the reference speed plus the max wind added value. An output device outputs an alert if the received aircraft speed is greater than the set target speed plus a predefined error value when the received aircraft location is within a threshold value of a touchdown point.

Abstract: The invention relates to a device aboard an aircraft comprising output means configured to restore information relating to the aircraft status from aircraft systems, the device including a module providing interface between said output means and said aircraft systems, said module being configured to synthesize information from aircraft systems depending on predetermined behavior rules and to transmit said information thus synthesized to said output means.

Abstract: Part units of speech information are arranged in a predetermined order to generate a sentence unit of a speech information set. To each of a plurality of speech part units of the speech information, an attribute of “interrupt possible after reproduction” with which reproduction of priority interrupt information can be started after the speech part unit of the speech information is reproduced or another attribute of “interrupt impossible after reproduction” with which reproduction of the priority interrupt information cannot be started even after the speech part unit of the speech information is reproduced is set. When the priority interrupt information having a high priority rank than the speech information set being currently reproduced is inputted, if the attribute of the speech information being reproduced at the point in time is “interrupt impossible after reproduction,” then the priority interrupt information is reproduced after the speech information is reproduced.

Abstract: Methods, systems, and computer-readable storage media provide for selective Notice to Airmen (NOTAM) notifications to be made to the crew of an aircraft according to the relevance of the NOTAM to a selected phase of flight of the aircraft. According to embodiments described herein, NOTAMs are received and parsed for subject and status codes. The subject and status codes are used with the selected phase of flight to determine a relevance code each NOTAM according to a set of relevance rules. The relevance rules provide a level of relevance of the NOTAM to the phase of flight and trigger a type of notification according to that level of relevance.

Abstract: A method and system are disclosed herein for confirming a potentially unintended command given to a vehicle. The method includes, but is not limited to, receiving a command from an operator configured to cause actuation of a vehicle system. The method further includes, but is not limited to, detecting a condition of the vehicle. The method further includes, but is not limited to, determining, with a processor, that the command is inconsistent with the condition. The method still further includes, but is not limited to alerting the operator that the command is inconsistent with the condition.

Abstract: Method for dynamically limiting the inclinations of monoblock flight control surfaces (FCS) in an aircraft. Dynamic limitation of the FCS is activated if a stall susceptibility condition is detected in the current aircraft environment. The real-time calibrated airspeed of the aircraft, real-time angle of attack (AOA) of the aircraft, and real-time sideslip angle (AOS) of the aircraft are obtained. The aircraft parameters may be obtained via estimation if the measured values are deemed unsuitable. The real-time local AOA and AOS of the FCS are calculated based on the obtained aircraft parameters. The inclination of each of the FCS relative to the critical values is dynamically limited according to the calculated real-time local AOA and AOS of the FCS. The aircraft may be an unmanned aerial vehicle (UAV) and/or a V-tail aircraft. The stall susceptibility condition may include icy conditions.

Abstract: In a drive control apparatus (1) of a hybrid vehicle, a provisional target engine power calculator (17D) of a controller (17) compares provisional target engine power which is calculated from a target drive power and a target charge/discharge power with a target engine power lower limit value and, when the provisional target engine power is smaller than the target engine power lower limit value, sets the target engine power lower limit value to the provisional target engine power.

Abstract: Apparatus and methods for controlling a system that operates responsive to a plurality of input control signals are disclosed. During operation the system generates a plurality of output status/control signals. A master controller has at least first and second controllers. The first controller outputs and inputs signals over a first communication path, and the second controller outputs and inputs signals over a second communication path. The first and second controllers output signals based on input signals received over the first and second communication paths, respectively, and also based on stored control data. A plurality of input/output modules are provided. Each of the input/output modules has first and second slave controllers. The first slave controller of each of the input/output modules inputs and outputs signals over the first communication path to the first controller, and the second slave controller outputs and inputs signals over the second communication path.