A hybrid rotary wireless and electrical slip ring transmission method

Abstract

The application belongs to the technical field of rotary inertial navigation electrical system design, and discloses a rotary wireless and electric slip ring hybrid transmission method, wherein key signals are transmitted wirelessly, and power or part of non-key signals are transmitted through an electric slip ring; in wireless transmission, first, multi-path signals including IMU data, a synchronous clock, motor drive control signals and frame angle measurement data are combined to convert into one high-bandwidth serial data; then, the serial data electrical signal is converted into a wireless signal and then into an electrical signal in the shaft system of the rotating frame, and the conversion is full duplex; finally, the combined signals are restored into multi-path original signals at the receiving end. The reliability and transmission bandwidth are improved, while the volume, weight, cost and transmission time delay are not increased.

Description

Technical Field

[0001] This invention belongs to the field of design technology for rotating inertial electrical systems, specifically relating to a hybrid transmission method combining rotating wireless and electric slip rings. Background Technology

[0002] Rotating inertial navigation systems (INS) require the transmission of power and signals along the rotating frame. Power supplies include those for the IMU, angle sensors, and motor drives. Signals include IMU data, synchronization clock, motor drive control signals, and frame angle measurement data. These power supplies and signals are numerous and varied, and their installation locations are dispersed. As the number of rotating frames increases (up to a maximum of three levels), the transmission scheme becomes increasingly complex.

[0003] Traditional rotating frames use conductive slip rings for power and signal transmission. Conductive slip rings are prone to reliability degradation due to long-term wear. The most common failure mode is resistance fluctuation, which can cause increased glitches in digital signals, waveform distortion, clock mis-triggers, and data packet loss. Summary of the Invention

[0004] This invention improves the signal transmission of rotating inertial navigation systems by changing it from conductive slip ring transmission to wireless transmission, thereby enhancing reliability and transmission bandwidth without increasing size, weight, cost, or transmission latency.

[0005] This invention provides a rotary wireless and electric slip ring hybrid transmission method, which transmits key signals wirelessly and transmits power or some non-key signals via the electric slip ring; the key signals include at least: IMU data, synchronization clock, motor drive control signal, and frame angle measurement data; In wireless transmission, multiple signals including IMU data, synchronization clock, motor drive control signal, and frame angle measurement data are first combined and converted into a single high-bandwidth serial data. Then, the serial data electrical signal is converted from electrical signal to wireless signal and back to electrical signal within the axis of the rotating frame, which is converted to full-duplex. Finally, at the receiving end, the combined signal is restored to the original multiple signals.

[0006] Furthermore, the hybrid transmission method combining wireless and electric slip rings adopts an integrated or separate design. The integrated design integrates a full-duplex wireless transmission module and multiple conductive slip rings in one structure, simultaneously realizing signal and power transmission; the separate design installs the wireless transmission device and conductive slip rings in two separate axes of the rotating frame.

[0007] Furthermore, the signal is combined according to the priority of transmission delay for each signal, and the transmission queue sends signals in order from strict to lenient according to the delay requirements.

[0008] Furthermore, the signal combining is implemented as follows: Step 1: The synchronization clock with the most stringent latency requirements is transmitted periodically in a token manner; Step 2: Other types of signals are converted into data packets. After the software completes the filling of each data packet, it informs the FPGA logic to send it out using an identifier. Step 3: Monitor the transmission cycle of the FPGA logic clock. Before each data packet is sent, determine the transmission duration of the data packet. If the remaining duration is insufficient to send the data packet completely, delay the transmission of the data packet. Step 4: To avoid conflicts between software input and FPGA logic transmission on the data buffer, the data buffer is designed as a double buffer.

[0009] Furthermore, the combined electrical signal uses LVDS or other differential methods, with the bandwidth rate controlled within 100Mbps, and ordinary electrical connectors and twisted-pair shielded cables are used for wiring and transmission in the rotating frame.

[0010] Furthermore, full-duplex electrical-wireless-electrical conversion is achieved within the rotating shaft system. Wireless transmission is implemented using a pair of PCBs, and the conversion chip on the PCB uses millimeter wave or infrared light.

[0011] Furthermore, the millimeter-wave wireless solution designs a full-duplex circularly polarized antenna array on the PCB board, consisting of four dual-line polarized units fed by rotation. A pair of PCBs are installed close together in the axis to achieve full-duplex communication, while five parasitic patches are loaded in the array.

[0012] Furthermore, the infrared wireless solution integrates a laser and a detector on a PCB board. The laser is the transmitter and the detector is the receiver. A pair of PCBs are installed close together in the axis to achieve full-duplex communication. The distance is designed based on the emission power, spot radius and detector sensitivity.

[0013] Furthermore, for multi-frame rotating inertial navigation systems, each frame has signals to be combined and split. A logic chip is integrated on the stator or rotor end of the wireless transmission PCB to realize the signal splitting and combining function interface of the frame.

[0014] Compared with the prior art, the present invention has the following advantages: This invention proposes a method and device for transmitting signals in rotating inertial navigation frames based on wireless transmission. It merges multiple differentiated signals into a single signal, replacing the original conductive slip ring transmission design and overcoming the inherent reliability issues caused by wear of conductive slip rings. This improves signal transmission reliability and bandwidth without increasing size, weight, cost, or transmission delay. It can be widely applied in rotating products. Attached Figure Description

[0015] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. The drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0016] Figure 1 This is a schematic diagram illustrating the installation of the two hybrid wireless and electric slip ring transmission schemes of the present invention; Figure 2 Shaft mounting for the wireless transmission device of the present invention; Figure 3 This is a schematic diagram of the PCB antenna design for the millimeter-wave wireless transmission device of the present invention; Figure 4 This invention provides a wireless transmission device using an infrared light module. Figure 5 This is a schematic diagram of the multi-rotation frame combined and split hybrid transmission scheme of the present invention; Figure 6 This is a schematic diagram of the single-axis rotating inertial navigation system of the present invention. Detailed Implementation

[0017] The present invention will be further described in detail below with reference to the embodiments and accompanying drawings, but the embodiments of the present invention are not limited thereto.

[0018] This invention provides a rotary wireless and electric slip ring hybrid transmission method that transmits critical signals wirelessly and transmits power or some non-critical signals via an electric slip ring.

[0019] The wireless transmission method first combines multiple signals, including inertial calculation data, synchronization clock, PWM control signal, and angle measurement signal, into a single high-bandwidth serial data stream. Then, the serial data electrical signal is converted from electrical signal to wireless signal and back to electrical signal within the axis of the rotating frame, achieving full-duplex conversion. Finally, at the receiving end, the combined signal is restored to the original multiple signals for software use.

[0020] The hybrid transmission method combining wireless and electric slip rings can be implemented in an integrated or separate design. The integrated design combines a full-duplex wireless transmission module and multiple conductive slip rings within a single structure, simultaneously transmitting signals and power. The separate design installs the wireless transmission device and the conductive slip rings separately in two axes of the rotating frame. (See diagram) Figure 1 .

[0021] Signal combining and splitting can be implemented using logic. The combining design is based on the priority of each signal's transmission delay, and the transmission queue sends signals in order from strict to lenient according to the delay requirements.

[0022] The logic for merging is described as follows: Step 1: The synchronization clock with the most stringent latency requirements is transmitted periodically in a token manner; Step 2: Other types of signals are converted into data packets. The software uses an identifier to inform the logic to send each completed data packet. Step 3: Monitor the sending cycle of the logic monitoring clock. Before sending each data packet, determine the sending duration of the data packet. If the remaining duration is insufficient to send the data packet completely, delay the sending of the data packet. Step 4: To avoid conflicts between software input and logical transmission on the data buffer, the transmission logic should be designed as a double buffer.

[0023] For combined electrical signals, differential methods such as LVDS are recommended, with bandwidth rates controlled within 100Mbps. Ordinary electrical connectors and twisted-pair shielded cables can be used for cabling and transmission within a rotating frame.

[0024] Achieving full-duplex conversion between electrical-wireless and electrical within a rotating shaft system, illustrated. Figure 2 Wireless transmission is implemented using a PCB design, and the conversion chip can use millimeter wave or infrared light.

[0025] The millimeter-wave wireless solution designs a full-duplex circularly polarized antenna array on a PCB board. It consists of four dual-polarized elements with high isolation and gain, fed by rotation. A pair of PCBs are mounted close together within the axis to achieve full-duplex communication. Furthermore, by loading five parasitic patches into the array, the radiation field distribution is made uniform, thereby improving the antenna's gain and isolation. (Illustration) Figure 3 The selection of electrical and millimeter-wave conversion chips covers a bandwidth range of 100Mbps.

[0026] The infrared wireless solution integrates a laser and a detector on a PCB board. The laser acts as the transmitter, and the detector as the receiver. A pair of PCBs are mounted close together within the same axis to achieve full-duplex communication. The distance is determined based on the emission power, spot radius, and detector sensitivity. (Illustration) Figure 4 The selection of electrical and infrared light conversion chips covers a bandwidth range of 100Mbps.

[0027] For multi-frame rotating inertial navigation systems, each frame has signals to be combined and split, which is difficult to accomplish in a single logic chip. Therefore, a logic chip can be integrated at the stator or rotor end of the wireless transmission PCB to implement the signal splitting and combining functions for that frame. (Illustration) Figure 5 .

[0028] Example 1: like Figure 6A method for transmitting signals using a rotating inertial navigation frame based on wireless transmission includes a single-axis rotating frame, signal combining and splitting circuits within the frame, signal combining and splitting circuit stages outside the frame, conductive slip rings, a wireless transmission device, and transmission harnesses.

[0029] Power is transmitted via conductive slip rings. Signals are split and combined by FPGA logic in both internal and external circuits to form a pair of full-duplex LVDS signals. The electrical and wireless signals are then converted via a transmission harness in the wireless transmission device.

[0030] Example 2: like Figure 5 A method for transmitting signals using a rotating inertial navigation frame based on wireless transmission includes a three-axis rotating frame, signal combining and splitting circuits within the frame, signal combining and splitting circuits outside the frame, three conductive slip rings, three pairs of wireless transmission devices (two of which have built-in combining and splitting FPGAs), an angle measuring device, a motor driver, and a transmission harness.

[0031] Power supplies (including the angle measuring devices, drivers, and power supplies for the internal circuitry of each rotating frame) are transmitted via conductive slip rings. Signals within the frame (including inertial data and synchronization clock) are combined and split within the FPGA of the internal circuitry, forming a pair of full-duplex LVDS signals, which are then transmitted to the wireless device in rotating frame one for electrical-to-wireless signal conversion. In the wireless transmission device of rotating frame two, the FPGA's combining and splitting functions fuse the inner frame angle measuring and driver signals, then combine them again into a pair of full-duplex LVDS signals, again converting them to electrical-to-wireless signals. Similarly, in the wireless transmission device of rotating frame three, the FPGA's combining and splitting functions fuse the middle frame angle measuring and driver signals, then combine them again into a pair of full-duplex LVDS signals, again converting them to electrical-to-wireless signals. Finally, the converted LVDS signals are transmitted to the external combining and splitting circuitry. The FPGA logic then reconstructs these signals into inertial data, synchronization clock, angle measuring, and control signals.

[0032] The above detailed embodiments are a description of the present invention. It should not be considered that the specific embodiments of the present invention are limited to these descriptions. For those skilled in the art, several simple deductions and substitutions can be made without departing from the concept of the present invention, and all of these should be considered to fall within the protection scope of the present invention.

Claims

1. A method for hybrid transmission of rotary wireless and electric slip ring, characterized in that, Key signals are transmitted wirelessly, while power or some non-critical signals are transmitted via an electric slip ring. Key signals include at least: IMU data, synchronous clock, motor drive control signal, and frame angle measurement data; In wireless transmission, multiple signals including IMU data, synchronization clock, motor drive control signal, and frame angle measurement data are first combined and converted into a single high-bandwidth serial data. Then, the serial data electrical signal is converted from electrical signal to wireless signal and back to electrical signal within the axis of the rotating frame, which is converted to full-duplex. Finally, at the receiving end, the combined signal is restored to the original multiple signals.

2. The method for hybrid transmission of rotary wireless and electric slip ring according to claim 1, characterized in that, The hybrid transmission method combining wireless and electric slip rings can be either integrated or split-type. The integrated design combines a full-duplex wireless transmission module and multiple conductive slip rings into a single structure, enabling both signal and power transmission. The split-type design installs the wireless transmission device and the conductive slip rings in two separate axes of the rotating frame.

3. The method for hybrid transmission of rotary wireless and electric slip ring according to claim 2, characterized in that, The signal is combined according to the priority of transmission delay for each signal, and the transmission queue sends signals in order from strict to lenient according to the delay requirements.

4. The method for hybrid transmission of rotary wireless and electric slip ring according to claim 3, characterized in that, Signal combining is implemented as follows: Step 1: The synchronization clock with the most stringent latency requirements is transmitted periodically in a token manner; Step 2: Other types of signals are converted into data packets. After the software completes the filling of each data packet, it informs the FPGA logic to send it out using an identifier. Step 3: Monitor the transmission cycle of the FPGA logic clock. Before each data packet is sent, determine the transmission duration of the data packet. If the remaining duration is insufficient to send the data packet completely, delay the transmission of the data packet. Step 4: To avoid conflicts between software input and FPGA logic transmission on the data buffer, the data buffer is designed as a double buffer.

5. The method for hybrid transmission of rotary wireless and electric slip ring according to claim 4, characterized in that, The combined electrical signal uses LVDS differential mode, with the bandwidth rate controlled within 100Mbps. Ordinary electrical connectors and twisted-pair shielded cables are used for wiring and transmission in the rotating frame.

6. The method for hybrid transmission of rotary wireless and electric slip ring according to claim 1, characterized in that, Full-duplex conversion between electrical and wireless transmission is achieved within the rotating shaft system. Wireless transmission is implemented using a pair of PCBs, and the conversion chip on the PCB uses millimeter wave or infrared light.

7. The method for hybrid transmission of rotary wireless and electric slip ring according to claim 6, characterized in that, The millimeter-wave wireless solution designs a full-duplex circularly polarized antenna array on a PCB board, consisting of four dual-line polarized elements fed by rotation. A pair of PCBs are installed close together in the axis to achieve full-duplex communication, and five parasitic patches are loaded in the array.

8. The method for hybrid transmission of rotary wireless and electric slip ring according to claim 6, characterized in that, The infrared wireless solution integrates a laser and a detector on a PCB board. The laser is the transmitter and the detector is the receiver. A pair of PCBs are installed close to each other in the axis to achieve full-duplex communication. The distance is designed based on the emission power, spot radius and detector sensitivity.

9. The method for hybrid transmission of rotary wireless and electric slip ring according to claim 1, characterized in that, For multi-frame rotating inertial navigation systems, each frame has signals to be combined and split. A logic chip is integrated on the stator or rotor end of the wireless transmission PCB to realize the signal splitting and combining function interface of the frame.

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