CN104063575B - Method for designing width and longitudinal length of planet vehicle moving system - Google Patents

Abstract

The invention belongs to the technical field of vehicles, relates to a method for designing the width and the longitudinal length of a planet vehicle moving system and is suitable for designing the longitudinal and transverse sizes of a planet vehicle. The method comprises the following steps: firstly, building a function relationship of the safety driving distance of the planet vehicle on the planet surface, determined by the ground clearance of the planet vehicle; secondly, building a function relationship of the safety driving distance of the planet vehicle on the planet surface, determined according to the transverse inclination conditions allowed by the planet vehicle; thirdly, building a function relationship of the safety driving distance of the planet vehicle on the planet surface, determined according to the longitudinal inclination conditions allowed by the planet vehicle; finally, building a function between the average driving distance Lf of the planet vehicle before the planet vehicle meets an insuperable barrier and the width of the planet vehicle, and determining the value ranges of the width B and the longitudinal length L of the planet vehicle moving system. According to the method, the longitudinal and transverse shape sizes of the planet vehicle moving system are designed, so that the average driving distance Lf of the planet vehicle before the planet vehicle meets the insuperable barrier can be maximized.

Description

A kind of celestial body car mobile system width and longitudinal length method for designing

Technical field

The invention belongs to technical field of vehicle, it is related to a kind of celestial body car mobile system width and longitudinal length method for designing, It is applied to celestial body car longitudinally, laterally size design.

Background technology

Fully prove from landing on the moon, data that areographic celestial body car is passed back, celestial body surface exists a large amount of Compactness surface stone, some stones are that celestial body car cannot be gone beyond, impassable in order to allow celestial body car hide those Stone, walks in stone forest, and the longitudinal and transverse size of appropriate design celestial body car is most important.The main base area of general method for designing The design theory of face vehicle and experience are designed, and do not have science to consider celestial body environment, lack effective theoretical foundation it is impossible to protect Card celestial body car design is optimum.The celestial body car that designs according to the method is it is also possible in the actual walking in celestial body surface, but can not protect Card celestial body car is running into the maximum of the average travel before impassable obstacle.

Content of the invention

The technical problem to be solved in the present invention is to provide a kind of celestial body car mobile system width and longitudinal length method for designing. The angle of the effectiveness travelling along celestial body surface from celestial body car so as to get celestial body car running into impassable obstacle Average travel before reaches maximum.

The technical scheme is that, a kind of celestial body car mobile system width and longitudinal length method for designing, the method bag Include following steps:

Step 1, obtain following parameters function according to the condition needing to meet of celestial body car:

(1) according to celestial body car terrain clearance determine the distance that can drive safely on celestial body surface functional relationship such as Under:

$l_{\mathrm{ld}}=\frac{s}{{(b+h_l\·k_v)\·k\·\left(h_l\right)}^n}-l-l_m-h_l\·k_f$

In formula, the implication of each parameter is:

l_ldThe operating range of the celestial body car being determined according to terrain clearance；

The width of b celestial body car mobile system；

k_vThe coefficient of stone near celestial body car；

The predetermined moving area area of s celestial body car；

K and n stone breadth coefficient；

h_lChassis minimum point terrain clearance value；

The longitudinal length of l celestial body car mobile system；

k_fStone is in the ratio of width to height of celestial body surface above section；

l_m- the shortest braking distance or acceleration distance；

B*l is a constant；

(2) letter of the distance that can drive safely on celestial body surface of the lateral inclination conditional decision permitted according to celestial body appearance of vehicle Number relation is as follows:

$l_1=\frac{s}{{(b+h_{\mathrm{kk}}\·k_v)\·k\·\left(h_{\mathrm{kk}}\right)}^n}-l-l_m-h_{\mathrm{kk}}\·k_f$

h_kkTilt tolerant height on celestial body car axis of pitch；

(3) letter of the distance that can drive safely on celestial body surface of the fore-and-aft tilt conditional decision permitted according to celestial body appearance of vehicle Number relation is as follows:

$l_d=\frac{s}{(b+h_{\mathrm{kd}}\·k_v)\·k\·{h_{\mathrm{kd}}}^n}-l-l_m-h_{\mathrm{kd}}\·k_f$

h_kdTilt tolerant height during celestial body car longitudinal driving；

Step 2, set up celestial body car average travel l before running into impassable obstacle_fWith celestial body vehicle-width it Between functional relationship:

l_f=min(l_ld,l_d, l₁)

Step 3, foundation l_fThe value condition determining, and the value of other specification, determine the width of celestial body car mobile system Degree b, the span of longitudinal length l.

The solution have the advantages that: the celestial body car mobile system longitudinally, laterally profile of the method according to the invention design Size, average travel before running into impassable obstacle for the celestial body car can be made to reach, and maximum (celestial body car is to can not Average travel between the obstacle gone beyond reaches maximum).

Brief description

The present invention has 1 width accompanying drawing.

Fig. 1 is a kind of celestial body car mobile system width and the longitudinal length method for designing of the present invention, runs into impassable Average distance (l before obstacle_f) relation curve and celestial body vehicle-width (b) between；Wherein k=0.5;k_l=0.4m.

Specific embodiment

Below the present invention is described in further detail.

A kind of celestial body car mobile system (the abbreviation celestial body car) width of the present invention and longitudinal length method for designing, its feature exists In,

Implementation steps are as follows:

Step one,

1) first celestial body car is calculated according to car body terrain clearance, ambient parameter (celestial body surface stone distribution statisticses rule) Length l in the path of safety traffic_ld.

According to celestial body car terrain clearance determine celestial body surface celestial body car can drive safely apart from l_ldFunction close System is as follows:

$l_{\mathrm{ld}}=\frac{s}{{(b+h_l\·k_v)\·k\·\left(h_l\right)}^n}-l-l_m-h_l\·k_f$

In formula, the implication of each parameter is:

l_ldThe operating range of the celestial body car being determined according to terrain clearance；

The width of b celestial body car movement；

k_vThe coefficient of stone near celestial body car；

The predetermined moving area area of s celestial body car is it is stipulated that celestial body car requires the expected test surface knot scope reaching；

K and n stone breadth coefficient；

h_lTerrain clearance value；

The longitudinal length of l celestial body car；

k_fStone is in the ratio of width to height of celestial body surface above section；

l_m- required operating range of causing danger is avoided using requisite measure.(in order to cross impassable obstacle or Operating range, typically short braking distance or acceleration distance required for unpowered maneuver in time).

Wherein, the predetermined moving area area s of celestial body car, the width b of celestial body car movement and the longitudinal length l's of celestial body car Product, chassis minimum point terrain clearance h_l, inclined height h that celestial body car is allowed in longitudinal axiss_kd, celestial body car allows in lateral shaft Inclined height h_kk, the shortest braking distance or acceleration distance l_m, be given as the known conditions designing celestial body car, b is celestial body car The width of movement it is believed that being the width of celestial body car, for require determine parameter value.k_v、k_fAs the known conditions being given, k_vPreferred scope is 0.1 1, k_fPreferred value is 1.5.

Radius of wheel is suitable with d, k_vTake 0.5；Radius of wheel is more than d, k_vTake 0.5-1, radius of wheel is less than d, k_vTake 0.1- 0.5, d be require across stone size, the celestial body car of design need across stone size, refer generally to height.

K and n is stone breadth coefficient, relevant with block sizes of interest in predetermined moving area area, by the spot The applied statistics matching such as observation, photo obtains；It determines that method generally adopts technological means commonly used in the art, for example:

By formula

n_k=k dⁿ

It is calculated k value.Wherein, n in formula_kIt is more than the quantity of the stone of d for certain area inside dimension.According to from celestial body The photo that surface is taken, counts the quantity that size is more than the stone of d, as n_k, basic index n takes -3(according to multiple photos, presses According to said method obtain multiple with regard to k and n equation, through over-fitting, obtain n=-3), substitute into above-mentioned formula and be calculated the value of k.

2) determine the safety traffic of celestial body car apart from l according to lateral inclination condition₁.

The function of the distance that can drive safely on celestial body surface of the lateral inclination conditional decision permitted according to celestial body appearance of vehicle Relation is as follows:

$l_1=\frac{s}{{(b+h_{\mathrm{kk}}\·k_v)\·k\·\left(h_{\mathrm{kk}}\right)}^n}-l-l_m-h_{\mathrm{kk}}\·k_f$

In formula, the implication of each parameter is,

l₁The operating range of the celestial body car being determined according to the sideways pitch allowed；

h_kkTilt tolerant height on celestial body car axis of pitch；

On identical parameters implication is shown in.

3) determine the safety traffic of celestial body car apart from l according to fore-and-aft tilt condition_d.

The function of the distance that can drive safely on celestial body surface of the fore-and-aft tilt conditional decision permitted according to celestial body appearance of vehicle Relation is as follows:

$l_d=\frac{s}{(b+h_{\mathrm{kd}}\·k_v)\·k\·{h_{\mathrm{kd}}}^n}-l-l_m-h_{\mathrm{kd}}\·k_f$

l_dThe operating range of the celestial body car being determined according to sideways pitch；

h_kdTilt tolerant height during celestial body car longitudinal driving；

On identical parameters implication is shown in.

Step 2, set up the average travel l between impassable obstacle for the celestial body car_f(i.e. celestial body car runs into not Average travel before the obstacle that can go beyond) functional relationship and celestial body vehicle-width between, therefore, order

l_f=min(l_ld,l_d, l₁)

Reach the judgment criterion of maximum according to above-mentioned mobile system average travel, determine that celestial body car is running into and can not exceed Before obstacle more, the function establishment principle of the average distance travelling is to take l_ld,l_dAnd l₁Minima, that is, celestial body car is longitudinal and transverse Criterion to dimensionally-optimised design is that the function of celestial body car average travel lf before running into impassable obstacle is set up Principle is the minima taking in three.

Step 3, foundation l_fNeed the value (condition of requirement) of other specification in the condition of satisfaction, and design, determine The span of celestial body vehicle-width, that is, obtain the width of celestial body car.

The condition meeting determined by the following example of the present invention is to make celestial body car before running into impassable obstacle Average distance be the bigger the better.

Concrete calculated examples are as follows:

In order to evaluate the effectiveness that celestial body car travels along the celestial body surface being covered with stone, using following initial data:

1st, projected area on celestial body surface for the celestial body car is constant, b*l=1m²；

2nd, celestial body vehicle-width β excursion 0.2 2m；

3rd, celestial body vehicle commander degree determines l=(b*l)/b=1/b according to celestial body car area；

4th, terrain clearance h_lExcursion is 0.2 0.6m；

5th, inclined height h that celestial body car is allowed in longitudinal axiss_kd=0.5*l；

6th, inclined height h that celestial body car is allowed in lateral shaft_kk=0.5*b；

7th, for motor-driven apart from l_m=0.5*l；

8th, coefficient k_vEqual to 0.5, coefficient k_fEqual to 1.5.

k_vIt is the size determination of the stone according to surrounding, in order to ensure vehicle safe driving, when stone is less, The impact that stone travels, therefore, k can not be considered to vehicle_vCan any value；When the size of stone is larger, stone Size impacts to the traveling of vehicle, and its value can be between 0.1 1.

k_fIt is stone the ratio of width to height in celestial body surface above section, in order to ensure celestial body car safety, should be naked on the ground in stone The k of dew portion size_fIn the distance again stops, k_fTypically take the value more than 1.

In s=100m²Region in, when distributed constant k changes in the range of 0.1 to 1, take n to be equal to -3.

The driveability in the different region on the photo taking from martian surface can be evaluated, parameter k and n according to According to the photo taking from martian surface, obtained by statistical fit.General k=0.1 correspond to there is a small amount of stone on photo, relatively Flat surfaces；K=1 correspond to the surface having a lot of stones on photo；The corresponding surface covering raft rock of k > 1 value.

In the case of moderate quatity block faces, take k=0.5；Terrain clearance h_lIn the case of=0.4m, by the design The celestial body vehicle-width that method obtains is as shown in Figure 1 with the relation curve in the average distance running into before impassable obstacle.

Under normal circumstances, the length: width of vehicle is big, therefore when abscissa is less than 1, length l=(the b*l)/b of vehicle =1/b, less than the width of vehicle, therefore, the value of b should select in the range of less than 1.

The design considerationss of celestial body vehicle-width should make average distance before running into impassable obstacle for the celestial body car get over Big better.

By shown curve it is recognised that in the case that width takes 0.8m, celestial body car is running into impassable barrier Average distance before hindering is maximum, so the optimum width of the transverse profile of celestial body car mobile system is 0.8, or it is vertical The long width of optimum ratio 1.25 to overall dimensions.

Fig. 1 illustrates celestial body vehicle-width and the relation curve in the average distance running into before impassable obstacle.By institute The curve that illustrates is it can be seen that the optimum ratio of the overall dimensions of mobile system and its longitudinal overall dimensions.

Claims (3)

1. a kind of celestial body car mobile system width with longitudinal length method for designing it is characterised in that the method comprises the following steps:

Step 1, obtain following parameters function according to the condition needing to meet of celestial body car:

(1) functional relationship of the distance that can drive safely on celestial body surface being determined according to celestial body car terrain clearance is as follows:

$l_{1d}=\frac{s}{(b+h_l\·k_v)\·k\·{\left(h_l\right)}^n}-l-l_m-h_l\·k_f$

In formula, the implication of each parameter is:

l_ldThe operating range of the celestial body car being determined according to terrain clearance；

The width of b celestial body car mobile system；

k_vThe coefficient of stone near celestial body car；

The predetermined moving area area of s celestial body car；

K and n stone breadth coefficient；

h_lChassis minimum point terrain clearance value；

The longitudinal length of l celestial body car mobile system；

k_fStone is in the ratio of width to height of celestial body surface above section；

l_m- the shortest braking distance or acceleration distance；

B*l is a constant；

(2) function of the distance that can drive safely on celestial body surface of the lateral inclination conditional decision permitted according to celestial body appearance of vehicle closes System is as follows:

$l_1=\frac{s}{(b+h_{kk}\·k_v)\·k\·{\left(h_{kk}\right)}^n}-l-l_m-h_{kk}\·k_f$

h_kkTilt tolerant height on celestial body car axis of pitch；

(3) function of the distance that can drive safely on celestial body surface of the fore-and-aft tilt conditional decision permitted according to celestial body appearance of vehicle closes System is as follows:

$l_d=\frac{s}{(b+h_{kd}\·k_v)\·k\·{h_{kd}}^n}-l-l_m-h_{kd}\·k_f$

h_kdTilt tolerant height during celestial body car longitudinal driving；

Step 2, set up celestial body car average travel l before running into impassable obstacle_fAnd celestial body vehicle-width between Functional relationship:

l_f=min (l_ld,l_d, l₁)

Step 3, foundation l_fThe value condition determining, and the value of other specification, determine the width b of celestial body car mobile system, The span of longitudinal length l.

2. a kind of celestial body car mobile system width according to claim 1 and longitudinal length method for designing it is characterised in that Described parameter can select following one group:

1) b*l=1m²；

2) celestial body vehicle-width b excursion 0.2 2m；

3) chassis minimum point terrain clearance h_lExcursion is 0.2 0.6m；

4) inclined height h that celestial body car is allowed in longitudinal axiss_kd=0.5*l；

5) inclined height h that celestial body car is allowed in lateral shaft_kk=0.5*b；

6)l_m=0.5*l；

7) the predetermined moving area area s=100m of celestial body car².

3. a kind of celestial body car mobile system width according to claim 1 and longitudinal length method for designing it is characterised in that The photo that parameters described below can be selected designs celestial body car mobile system width and longitudinal length:

1) coefficient k_v=0.5, coefficient k_f=1.5；

2) k=0.5, n=-3.