CN103234500B - Brake displacement measuring device for unmanned dynamic delta wing and calibration method thereof - Google Patents

Abstract

The invention discloses a brake displacement measuring device for an unmanned dynamic delta wing and a calibration method thereof. The brake displacement measuring device comprises a pull-wire seat, a brake wire, a pull-wire encoder, a pull-wire-encoder pull wire, a signal wire and a DSP (digital signal processor) plate. The pull-wire seat is fixed on a brake pedal, one end of the brake wire is connected on the pull-wire seat, and the other end of the brake wire is connected on a brake disc. The pull-wire encoder is fixedly connected with a wheel fork. One end of the pull-wire-encoder pull wire extends from the pull-wire encoder to be fixed on the brake wire. The pull-wire encoder is connected with the DSP plate through the signal wire, and transmits pull-wire displacement signals to the DSP plate. The DSP plate calculates the displacement of the brake wire according to the pull-wire displacement signals. On the basis that original front-wheel manipulated torque and braking force mechanical structure are not changed, a new measuring device is added, and manipulating safety of airplane ground running is not affected; and the brake displacement of the unmanned dynamic delta wing during automatic take-off and landing running can be measured in real time, and high-speed collection of real-time data is completed.

Description

Displacement Measuring Device and Calibration Method for Brake Displacement of Unmanned Powered Delta Wing

technical field

The invention belongs to the technical field of detection, and relates to a measuring device for braking displacement of an unmanned power delta wing and a calibration method thereof.

Background technique

The power delta wing is a light aircraft with power and good gliding performance. Its main features are: low cost, simple structure, quick disassembly and folding for vehicle, ship and air transportation; good ultra-low altitude flight performance; The descending distance is short, safe and reliable, and the operation is easy to learn. It can take off and land on grass, airstrips, and roads. Widely used in tourism, transportation, petrochemical pipeline survey, agricultural pest control, forest fire prevention and early warning, aerial photography, flight training, emergency rescue, police patrol, forbidden logging (fishing, hunting) and other restricted areas inspection, air command, environmental monitoring, special Combat operations, anti-terrorism in remote areas, anti-drug and anti-smuggling, and communication relay for emergency rescue tasks. It can also meet the needs of industries such as fishery, farm industry, beekeeping industry, geological survey industry, scientific investigation industry and sports.

The power delta wing has a large load, generally up to 250 kg. Therefore, refitting the power delta wing into an unmanned aerial vehicle will have obvious advantages, so the unmanned power delta wing will have significant economic benefits and practical value. However, since the unmanned power delta wing carries a large amount of load, in order to work reliably in all weathers, it is necessary to realize wheeled autonomous take-off and landing, so as to get rid of the dependence on the operator, and make it easier for the practical application and product promotion of the unmanned power delta wing. The autonomous take-off and landing function has become the most important flight capability of the unmanned powered delta wing.

But the premise of unmanned power delta wing design is to change the control device of manned power delta wing into unmanned electric device. In order to realize the autonomous take-off and landing function, it is necessary to electrically modify the brakes and front wheel steering; in order to select the output force of the electric device, it is necessary to adjust the brake displacement, front wheel steering torque/braking force when the manned delta wing is operated Measurements are taken to calculate the maximum required control force throughout the autonomous takeoff and landing ground roll.

Contents of the invention

(1) Technical problems to be solved

The technical problem to be solved by the present invention is to provide an unmanned power delta wing brake displacement measurement device to meet the measurement requirements for unmanned power delta wing brake displacement during autonomous take-off and landing on the ground.

(2) Technical solution

In order to solve the above technical problems, the present invention proposes a device for measuring the braking displacement of an unmanned power delta wing, which is used to measure the braking displacement of an unmanned power delta wing. disc and brake pedal, the main beam is fixedly connected with the wheel fork, the tire is installed on the wheel fork, and the brake disc is installed on the side of the wheel hub of the tire; the brake disc is controlled by the brake pedal to the The tire is stuck and braked, and the brake pedal can be moved automatically. The brake displacement measuring device includes a cable seat, a brake line, a cable encoder, a cable encoder cable, a signal line, and a DSP board; the cable seat is fixed on the on the brake pedal; one end of the brake wire is connected to the cable seat, and the other end is connected to the brake disc; the cable encoder is fixedly connected to the wheel fork; one end of the cable encoder cable is encoded from the cable After stretching out from the device, it is fixed on the brake line; the cable encoder is connected to the DSP board through the signal line, and transmits the cable displacement signal to the DSP board; the DSP board calculates the position according to the bit line displacement signal Describe the displacement of the brake line.

The present invention also proposes a calibration method of an unmanned power delta wing brake displacement measuring device at the same time, which is used for the calibration of the above-mentioned unmanned power delta wing brake displacement measuring device. The method includes the following steps: step S1, the wire encoder The measured data pulse is converted into the displacement of the cable of the cable encoder; step S2, calculating the displacement of the brake cable according to the displacement of the cable of the cable encoder.

(3) Beneficial effects

(1) The present invention adds a new measuring device on the basis of not affecting the original front wheel steering torque and braking dynamics structure, which will not affect the control safety of the aircraft ground roll.

(2) The present invention can measure the braking displacement of the unmanned power delta wing in the process of autonomous take-off and landing in real time, and complete the high-speed collection of real-time data.

Description of drawings

Fig. 1A and Fig. 1B are the schematic structural diagrams of the unmanned powered delta-wing front wheel device, wherein Fig. 1A is a side view, and Fig. 1B is a front view.

Fig. 2 is the structure and installation position schematic diagram of an embodiment of unmanned power delta wing braking displacement measuring device of the present invention;

Fig. 3 is the structural representation of the DSP board of unmanned power triangular wing braking displacement measuring device of the present invention;

Fig. 4 is a schematic diagram of the principle of non-linear correction of brake displacement in the present invention.

Detailed ways

In order to make the object, technical solution and advantages of the present invention clearer, the present invention will be further described in detail below in conjunction with specific embodiments and with reference to the accompanying drawings.

Fig. 1A and Fig. 1B are the structural schematic diagrams of the power triangular wing front wheel device, wherein Fig. 1A is a side view, and Fig. 1B is a front view. As shown in Fig. 1A and Fig. 1 B, front wheel device comprises main beam 101, swing arm 102, axle 103, brake disc 104, tire 105, wheel fork 106, brake pedal 107, left shock absorber 108, accelerator pedal 109, right Shock absorber 110, wheel cover 111. The main beam 101 is fixedly connected with the wheel fork 106, and the tire 105 is installed on the wheel fork 106. The wheel hub side of the tire 105 is equipped with a brake disc 104, and the brake disc 104 is controlled by the brake pedal 107 to brake the tire. For the unmanned power trike nose wheel device, the brake pedal 107 can move automatically.

Fig. 2 is a schematic diagram of the structure and installation position of the unmanned power delta wing brake displacement measuring device of the present invention. As shown in Figure 2, the brake displacement measuring device includes: cable seat 121, brake cable 122, bracket 123, right nylon pulley 124, left nylon pulley 125, cable encoder 126, deck 127, cable encoder cable 128, snap ring 129 , a signal line 130 , and a DSP board 131 .

The cable holder 121 is fixed on the brake pedal 107 and is generally located at the front of the brake pedal 107 . One end of the brake line 122 is connected to the cable seat 121, and the other end is connected to the brake disc 104, and the middle passes through the right nylon pulley 124 and the left nylon pulley 125 successively. One end of the support 123 is fixed on the wheel fork 106, and one end is suspended in the air; the left nylon pulley 125 and the right nylon pulley 124 are located at the left and right ends of the support 123 respectively, and the brake line 122 bypasses the right nylon pulley 124 and the left nylon pulley 125 successively. Connected to the wheel brake disc 104. The purpose of setting the bracket 123 is to install the right nylon pulley 124 and the left nylon pulley 125, to ensure that the brake line 122 is perpendicular to the brake pedal 107, and to improve the ratio of the brake pedal 107 displacement traction brake line 122 displacement.

The clamping seat 127 is fixedly connected with the wheel fork 106 , and can usually be installed at the middle and lower part of the wheel fork 106 . The wire-guide encoder 126 is fixed on the deck 127 , thereby being fixedly connected with the wheel fork 106 . Meanwhile, one end of the wire-guide encoder wire 128 protrudes from the wire-guide encoder 126 and is fixed on the brake wire 129 . Usually, this end can be fixed on the brake wire 122 through the snap ring 129, and the unextended end of the pull wire 128 can be connected to the inner shaft of the pull wire encoder 126 through elastic rollers or the like. The wire-drawing encoder 126 is connected to the DSP board 131 through the wire-drawing encoder signal line 130 , and transmits a wire-drawing displacement signal to the DSP board 131 . As shown in FIG. 2 , the signal line 130 can be arranged along the wheel fork 106 and connected to the DSP board 131 on the main beam 101 . The DSP board 131 is preferably a high-speed DSP board for receiving signals from the cable encoder 126 to measure the displacement of the brake cable.

The working process of the unmanned power delta wing brake displacement measuring device 1 is as follows:

Self-control brake pedal 107103, traction brake line 122 moves. Under the action of the snap ring 129, the cable encoder cable 128 moves with the brake cable 122, driving the cable encoder 126 to output the cable displacement signal, and the cable displacement signal is sent to the DSP board 131 through the signal line 130 for high-speed acquisition and recording.

Fig. 3 is a structural schematic diagram of the DSP board of the unmanned power delta wing brake displacement measuring device of the present invention. As shown in Figure 3, it includes: DSP main chip 1311, SD card 1312, RAM 1313, RS232 interface 1314, power supply 1315, quadrature encoder QEP interface 1316, AD interface 1317, SPI bus 1318, SCI bus 1319.

DSP master chip 1311 such as can adopt the DSP chip TMS320F28335 (main frequency 150Mhz) of TI Company, be connected with SD card 1312 by SPI bus 1318, be connected with RAM1313 through the external RAM interface that external chip carries, be connected with RS232 interface 1314 by SCI bus 1319 connected to the signal line 130 through the quadrature encoder QEP interface 1316.

DSP main chip 1311 is mainly used for data acquisition, system management, communication and data recording; SD card 1312 is mainly used for permanent data recording; RAM1313 is mainly used for temporary storage of collected data; RS232 interface 1314 is used for communication with PC for parameter setting; The power supply 1315 provides power for DSP and various peripherals, and outputs 5V, 3.3V and 1.8V. The quadrature encoder QEP interface 1316 is used to collect the quadrature encoding signal of the wire-drawn encoder 126 .

The present invention comprises for the calibration step for braking displacement (mm):

Step S1, converting the data pulse measured by the pull wire encoder 126 into the displacement of the pull wire 128;

Step S2 , calculating the displacement of the brake wire 122 according to the displacement of the pull wire 128 .

At first, in step S1, what the wire-drawn encoder 126 measured was the pulse amount P, if the pulse line number T of one circle of the wire-drawn encoder 126 adopts the quadrature encoding AB phase, and the pulse of one circle is 4T), the inner axle radius of the wire-drawn encoder 126 is R mm, then the conversion relationship between the pulse P and the wire displacement S is:

$\mathrm{<span\; class="notranslate">\; S</span>}<span\; class="notranslate">\; =</span>\frac{\mathrm{<span\; class="notranslate">\; P</span>}}{\mathrm{<span\; class="notranslate">\; 4</span>}\mathrm{<span\; class="notranslate">\; T</span>}}\mathrm{<span\; class="notranslate">\; 2</span>}\mathrm{<span\; class="notranslate">\; \&pi;R</span>}<span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; )</span>$

Next, step S2 will be described with reference to FIG. 4 . Fig. 4 is a schematic diagram of the principle of non-linear correction of brake displacement in the present invention. As shown in FIG. 4 , since the cable encoder cable 128 of the cable encoder 126 is installed non-parallel to the brake cable 122 , the reading of the cable encoder 126 needs to be corrected to form the brake displacement. During the braking process, the minimum stroke S _min (point B) and the maximum stroke S _max (point A) of the cable encoder 126 , and the current point of braking displacement is point N. Among them, the side deviation distance D and the maximum stroke S _max can be measured by a ruler. When the brake is executed, the reading of the cable encoder changes ΔP, and the actual stroke ΔS _e of the brake line 122 is (non-linear correction formula):

$<span\; class="notranslate">\; \{</span>\begin{array}{c}\mathrm{<span\; class="notranslate">\; \&Delta;S</span>}<span\; class="notranslate">\; =</span>\frac{\mathrm{<span\; class="notranslate">\; \&Delta;P</span>}}{\mathrm{<span\; class="notranslate">\; 4</span>}\mathrm{<span\; class="notranslate">\; T</span>}}\mathrm{<span\; class="notranslate">\; 2</span>}\mathrm{<span\; class="notranslate">\; \&pi;R</span>}\\ \mathrm{<span\; class="notranslate">\; \&Delta;</span>}{\mathrm{<span\; class="notranslate">\; S</span>}}_{\mathrm{<span\; class="notranslate">\; e</span>}}<span\; class="notranslate">\; =</span>\sqrt{{\mathrm{<span\; class="notranslate">\; S</span>}}_{\mathrm{<span\; class="notranslate">\; max</span>}}^{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; D.</span>}}^{\mathrm{<span\; class="notranslate">\; 2</span>}}}<span\; class="notranslate">\; -</span>\sqrt{{<span\; class="notranslate">\; (</span>{\mathrm{<span\; class="notranslate">\; S</span>}}_{\mathrm{<span\; class="notranslate">\; max</span>}}<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; \&Delta;S</span>}<span\; class="notranslate">\; )</span>}^{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; D.</span>}}^{\mathrm{<span\; class="notranslate">\; 2</span>}}}\end{array}<span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 2</span>}<span\; class="notranslate">\; )</span>$

Wherein: T is the number of lines in a circle of the wire-guide encoder 126, R is the radius of the inner wheel shaft of the wire-guide encoder 126, and ΔP is the variation of the pulse number of the wire-guide encoder 126 during the braking process.

The unmanned power delta wing brake displacement measuring device of the present invention can perform real-time measurement of the power delta wing brake displacement during the autonomous take-off and landing ground roll stage, and complete high-speed collection of real-time data with a sampling rate of 10Khz.

The specific embodiments described above have further described the purpose, technical solutions and beneficial effects of the present invention in detail. It should be understood that the above descriptions are only specific embodiments of the present invention, and are not intended to limit the present invention. Within the spirit and principles of the present invention, any modifications, equivalent replacements, improvements, etc., shall be included in the protection scope of the present invention.

Claims (8)

1. a unmanned dynamic-delta-wing brake displacement measuring device, for measuring the brake displacement of unmanned dynamic-delta-wing, described unmanned dynamic-delta-wing comprises girder (101), wheel fork (106), tire (105), brake flange (104) and brake pedal (107), described girder (101) is fixedly connected with wheel fork (106), described tire (105) is arranged on described wheel fork (106), and the wheel hub side of described tire (105) installs described brake flange (104); Described brake flange (104) carries out card by the control of brake pedal (107) to described tire (105) and stops, and described brake pedal (107) can automatically move, and it is characterized in that,

Described brake displacement measuring device comprises bracing wire seat (121), brake cable (122), draw wire encoder (126), draw wire encoder bracing wire (128), signal wire (130) and dsp board (131);

Described bracing wire seat (121) is fixed on described brake pedal (107);

Described brake cable (122) one end is connected on bracing wire seat (121), and one end is connected on described brake flange (104);

Described draw wire encoder (126) is fixedly connected with described wheel fork (106);

One end of described draw wire encoder bracing wire (128) is fixed in brake cable (122) after stretching out from draw wire encoder (126);

Described draw wire encoder (126) is connected with described dsp board (131) by described signal wire (130), and transmits bracing wire displacement signal to this dsp board (131);

Described dsp board (131) calculates the displacement of described brake cable according to this bracing wire displacement signal.

2. unmanned dynamic-delta-wing brake displacement measuring device as claimed in claim 1, it is characterized in that, also comprise support (123), described support (123) one end is fixed on wheel fork (106), and one end is unsettled; Left chain wheel (125) and right pulley (124) is separately installed with at the two ends, left and right of described support (123); Described brake cable (122) between described bracing wire seat (121) and brake flange (104) successively through described right pulley (124) and left chain wheel (125).

3. unmanned dynamic-delta-wing brake displacement measuring device as claimed in claim 1, it is characterized in that, also bag hand deck (127), described deck (127) is fixedly connected with described wheel fork (106), and described draw wire encoder (126) is fixed on this deck (127).

4. unmanned dynamic-delta-wing brake displacement measuring device as claimed in claim 1, it is characterized in that, described draw wire encoder bracing wire (128) is fixed in described brake cable (122) by snap ring (129).

5. unmanned dynamic-delta-wing brake displacement measuring device as claimed in claim 1, it is characterized in that, described dsp board (131) is High-Speed DSP Board.

6. unmanned dynamic-delta-wing brake displacement measuring device as claimed in claim 5, it is characterized in that, described dsp board (131) comprises orthogonal encoder QEP interface (1316), and it is for gathering the orthogonal intersection code signal of described draw wire encoder (126).

7. the scaling method of a unmanned dynamic-delta-wing brake displacement measuring device, the unmanned dynamic-delta-wing brake displacement measuring device of described unmanned dynamic-delta-wing brake displacement measuring device according to any one of claim 1 to 6, it is characterized in that, comprise the steps:

Step S1, the data pulse of measuring described draw wire encoder (126) are converted to the displacement of described draw wire encoder bracing wire (128);

Step S2, calculate the displacement of described brake cable (122) according to the displacement of described draw wire encoder bracing wire (128).

8. the scaling method of unmanned dynamic-delta-wing brake displacement measuring device as claimed in claim 7, is characterized in that, in step s 2, and the displacement according to following formulae discovery brake cable:

$\left\{\begin{array}{c}\mathrm{\&Delta;S}=\frac{\mathrm{\&Delta;P}}{4T}2\mathrm{\&pi;R}\\ \mathrm{\&Delta;}{S}_e=\sqrt{S_{\max }^2-D^2}-\sqrt{{(S_{\max }-\mathrm{\&Delta;S})}^2-D^2}\end{array}\right.,$ Wherein

Δ S _ebe the stroke of brake cable (122), Δ S is the change of bracing wire displacement, and D is lateral deviation distance, S _maxfor the range of draw wire encoder (126), Δ P is the change of draw wire encoder reading, and T is one week taps number of draw wire encoder (126), and R is the radius of draw wire encoder (126) inner hub.