CN102141794A - Continuous locus intersegment connecting speed processing method for numerical control system - Google Patents

Abstract

The invention discloses a continuous locus intersegment connecting speed processing method for a numerical control system, which comprises the following steps of: determining an adjacent two-segment locus connecting model, and acquiring the movement parameter of the adjacent two-segment locus to be processed; calculating the path length of the adjacent two-segment locus to be processed; calculating the speed of a connecting point of the adjacent two-segment locus under the conditions of acceleration, arch height error, instruction feeding speed and corner constraint; calculating the speed of the connecting point of the adjacent two-segment locus satisfying the condition S curve acceleration and deceleration control-based path length constraint of the front segment locus in the adjacent two-segment locus; and calculating the speed of the connecting point of the adjacent two-segment locus satisfying the condition S curve acceleration and deceleration control-based path length constraint of the rear segment locus in the adjacent two-segment locus, wherein the calculated speed is used as a final value of the adjacent two-segment locus connecting speed. The invention provides the continuous locus intersegment connecting speed processing method for numerical control equipment, so that the processing locus of the numerical control equipment is continuous and the speed is smooth.

Description

A kind of intersegmental linking velocity process of continuous path method that is used for digital control system

Technical field

The present invention relates to a kind of intersegmental linking velocity process of continuous path method that is used for digital control system in the method for planning track in the digital control system field, particularly numerically-controlled machine and the robot motion's control technology.

Background technology

In numerically-controlled machine processing and robot motion's control, trajectory planning occupies an important position.In machine tooling, trajectory planning mainly is that the speed of lathe is planned.For the numerically-controlled machine of continuous cutting, the control Significance of speed of feed is great.It not only directly influences the roughness and the precision of processing parts, and closely related with life-span, the production efficiency of cutter and lathe.In robot motion control, the robot operational process requires action continuously smooth and avoiding obstacles smoothly.

In practice, the processing of numerically-controlled machine and the motion of robot generally are made up of the multistage movement locus, if every section track to be processed is all adopted from the static target velocity that accelerates to, decelerate to zero method for planning track again, to reduce average speed of feed, influence working (machining) efficiency; And because the frequent start-stop of motor and acceleration and deceleration running, cause not only that surface of the work is coarse, precision is low, and the expanded motor load, electrical machinery life reduced.

At present, for addressing the above problem main employing continuous path planing method.In the continuous path planing method, acceleration and deceleration control method commonly used mainly is S curve acceleration and deceleration control methods.But the algorithm of the intersegmental linking speed of existing continuous path, not considering will be based on the path of adjacent two sections tracks of S curve acceleration and deceleration control as constraint condition, the actual feed that causes being connected the some place at adjacent two sections tracks does not reach precalculated speed, linking speed between adjacent two sections orbit segments produces sudden change, and speed of feed can not link up smoothly between adjacent two sections orbit segments; When part processing was finished, tool speed can not in time drop to zero, produces and cuts.

Summary of the invention

Purpose of the present invention aims to provide a kind of intersegmental linking velocity process of continuous path method that is used for digital control system, make that being connected an actual feed at place at adjacent two sections tracks can arrive precalculated speed, can link up smoothly between promptly adjacent two sections orbit segments.Digital control system does not need to thresh last spot speed accessibility judgement and adjustment when doing S curve acceleration and deceleration control, thereby improves digital control system acceleration and deceleration control efficient.

For realizing above-mentioned target, the technical solution adopted in the present invention is as follows:

Digital control system in the numerical control device is deciphered processing to the numerical control program in machine code, and store decode results into the decoding buffer zone, utilize the program segment information of deciphering in the buffer zone to the intersegmental linking velocity process of continuous path to be processed, make that the numerical control device machining locus is continuous, rate smoothing, the intersegmental linking velocity process of described continuous path method may further comprise the steps:

(1) determines that adjacent two sections tracks are connected model, and obtain the kinematic parameter of adjacent two sections tracks to be processed;

(2) calculate the path of adjacent two sections tracks to be processed;

(3) speed of the linking point of the adjacent two section tracks of calculating under acceleration, bow high level error, instruction speed of feed and turning constraint condition;

(4) calculate to satisfy speed based on the linking point of adjacent two sections tracks of the path length constraint condition of the leading portion track in adjacent two sections tracks of S curve acceleration and deceleration control;

(5) calculate to satisfy speed based on the linking point of adjacent two sections tracks of the path length constraint condition of the back segment track in adjacent two sections tracks of S curve acceleration and deceleration control, and as the end value of linking speed between adjacent two sections orbit segments.

The path of described adjacent two sections tracks to be processed comprises straight line path length and circular arc path length; Described circular arc path length calculation step comprises: (2.1) calculate the positive dirction angle in the horizontal axis of circular arc initial point place principal normal unit vector and workpiece coordinate system, (2.2) calculating is at the positive dirction angle of the horizontal axis of circular arc end point place's principal normal unit vector and workpiece coordinate system, and (2.3) calculate circular arc path length;

(2.1) calculate in circular arc initial point place principal normal unit vector

Positive dirction angle α with the horizontal axis of workpiece coordinate system _{I_s}:

$\sin {\mathrm{\α}}_{i\_s}=\frac{y_{i\_c}-y_i}{R_i}---\left(1\right)$

$\cos {\mathrm{\α}}_{i\_s}=\frac{x_{i\_c}-x_i}{R_i}---\left(2\right)$

Wherein: i=1,2,3...N, N represent orbit segment number to be processed; (x _i, y _i) be i section Track Initiation point coordinate; (x _{I_c}, y _{I_c}) be the central coordinate of circle of circular arc when i section track is circular arc; R _iBe the radius of circular arc when i section track is circular arc, get α by formula (1) and (2) _{I_s}Computing formula be:

(2.2) calculate principal normal unit vector at some place, circular arc end

Positive dirction angle α with the horizontal axis of workpiece coordinate system _{I_e}:

$\sin {\mathrm{\α}}_{i\_e}=\frac{y_{i\_c}-y_{i+1}}{R_i}---\left(4\right)$

$\cos {\mathrm{\α}}_{i\_e}=\frac{x_{i\_c}-x_{i+1}}{R_i}---\left(5\right)$

Wherein: (x _I+1, y _I+1) be i section track end point coordinate;

Get α by formula (4) and (5) _{I_e}Computing formula be:

(2.3) calculate circular arc path length S _i:

Get S by formula (3) and (6) _iComputing formula be:

Described path length constraint condition based on the leading portion track in adjacent two sections tracks of S curve acceleration and deceleration control is inequality group (8), (9) and (10):

$\left\{\begin{array}{c}|V_{i,T}-V_{i\_s}|\&GreaterEqual;\frac{a_{\max }^2}{J_{\max }}\\ S_i>2V_{i\_s}\frac{a_{\max }}{J_{\max }}+\frac{a_{\max }^3}{J_{\max }^2}\\ S_i<\frac{J_{\max }(V_{i,T}^2-V_{i\_s}^2)+a_{\max }^2(V_{i,T}+V_{i\_s})}{2J_{\max }{a}_{\max }}\end{array}\right.---\left(8\right)$

$\left\{\begin{array}{c}|V_{i,T}-V_{i\_s}|<\frac{a_{\max }^2}{J_{\max }}\\ S_i<(V_{i,T}+V_{i\_s})\sqrt{\frac{|V_{i,T}-V_{i\_s}|}{J_{\max }}}\end{array}\right.---\left(9\right)$

$\left\{\begin{array}{c}|V_{i,T}-V_{i\_s}|\&GreaterEqual;\frac{a_{\max }^2}{J_{\max }}\\ S_i\&le;{2V}_{i\_s}\frac{a_{\max }}{J_{\max }}+\frac{a_{\max }^3}{J_{\max }^2}\end{array}\right.---\left(10\right)$

Wherein: V _{I_s}Be the initial point speed of i section track; a _MaxPeak acceleration for the digital control system permission; J _MaxMaximum acceleration for the digital control system permission; S _iIt is the path of i section track; V _{I, T}Speed for the linking point of adjacent two sections tracks of under acceleration, bow high level error, instruction speed of feed and turning constraint condition, calculating;

When inequality group (8), (9) and (10) when all being false, the speed V of the linking point of the adjacent two sections tracks that calculate is described under acceleration, bow high level error, instruction speed of feed and turning constraint condition _{I, T}Can satisfy path length constraint condition, satisfy speed V based on the linking point of adjacent two sections tracks of the path length constraint condition of the leading portion track in adjacent two sections tracks of S curve acceleration and deceleration control based on the leading portion track in adjacent two sections tracks of S curve acceleration and deceleration control _{I, T_f}Equal V _{I, T}

When inequality group (8), (9) and (10) by and only form immediately by one, the speed V of the linking point of the adjacent two sections tracks that calculate under acceleration, bow high level error, instruction speed of feed and turning constraint condition is described _{I, T}Can not satisfy path length constraint condition, satisfy speed V based on the linking point of adjacent two sections tracks of the path length constraint of the leading portion track in adjacent two sections tracks of S curve acceleration and deceleration control based on the leading portion track in adjacent two sections tracks of S curve acceleration and deceleration control _{I, T_f}Computing method are: when inequality group (8) is set up, and V _{I, T_f}Calculate according to formula (11); When inequality group (9) or (10) establishment, V _{I, T_f}Calculate according to formula (12) and (13);

$V_{i,T\_f}=\frac{\sqrt{a_{\max }^4-4J_{\max }(a_{\max }^2{V}_{i\_s}-J_{\max }{V}_{i\_s}^2-2J_{\max }{a}_{\max }{S}_i)}-a_{\max }^2}{2J_{\max }}---\left(11\right)$

$V_{i,T\_f}=V_{i\_s}+J_{\max }{T}_{\mathrm{jerk}}^2---\left(12\right)$

$J_{\max }{T}_{\mathrm{jerk}}^3+2V_{i,T\_f}-S_i=0---\left(13\right)$

Wherein: T _JerkFor adding the time of accelerating sections;

Described path length constraint condition based on the back segment track in adjacent two sections tracks of S curve acceleration and deceleration control is inequality group (14), (15) and (16):

$\left\{\begin{array}{c}{V}_{i,T\_f}\&GreaterEqual;\frac{a_{\max }^2}{J_{\max }}\\ S_{i+1}>2V_{i,T\_f}\frac{a_{\max }}{J_{\max }}+\frac{a_{\max }^3}{J_{\max }^2}\\ S_{i+1}<\frac{a_{\max }^2{V}_{i,T\_f}-J_{\max }{V}_{i,T\_\mathrm{<figure-callout\; id="2"\; label="f"\; filenames="HSA00000439941900031.png"\; state="\{\{state\}\}">f</figure-callout>}}^2}{2J_{\max }{a}_{\max }}\end{array}\right.---\left(14\right)$

$\left\{\begin{array}{c}{V}_{i,T\_f}<\frac{a_{\max }^2}{J_{\max }}\\ S_{i+1}<V_{i,T\_f}\sqrt{\frac{V_{i,T\_f}}{J_{\max }}}\end{array}\right.---\left(15\right)$

$\left\{\begin{array}{c}{V}_{i,T\_f}\&GreaterEqual;\frac{a_{\max }^2}{J_{\max }}\\ S_{i+1}\&le;{2V}_{i,T\_f}\frac{a_{\max }}{J_{\max }}+\frac{a_{\max }^3}{J_{\max }^2}\end{array}\right.---\left(16\right)$

Wherein: S _I+1It is the path of i+1 section track; V _{I, T_f}For satisfying speed based on the linking point of adjacent two sections tracks of the path length constraint condition of the leading portion track in adjacent two sections tracks of S curve acceleration and deceleration control;

When (14), (15) and (16) when all being false, the speed V that satisfies based on the linking point of adjacent two sections tracks of the path length constraint condition of the leading portion track in adjacent two sections tracks of S curve acceleration and deceleration control is described _{I, T_f}Can satisfy path length constraint condition, satisfy speed V based on the linking point of adjacent two sections tracks of the path length constraint condition of the back segment track in adjacent two sections tracks of S curve acceleration and deceleration control based on the back segment track in adjacent two sections tracks of S curve acceleration and deceleration control _{I, T_l}Equal V _{I, T_f}

When inequality group (14), (15) and (16) by and only form immediately by one, the speed V that satisfies based on the linking point of the path length constraint condition of the leading portion track in adjacent two sections tracks of S curve acceleration and deceleration control is described _{I, T_f}Can not satisfy path length constraint condition, satisfy speed V based on the linking point of adjacent two sections tracks of the path length constraint condition of the back segment track in adjacent two sections tracks of S curve acceleration and deceleration control based on the back segment track in adjacent two sections tracks of S curve acceleration and deceleration control _{I, T_l}Computing method are: when inequality group (14) is set up, and V _{I, T_l}Calculate according to formula (17); When inequality group (15) or (16) establishment, V _{I, T_l}Calculate according to formula formula (18);

$V_{i,T\_l}=\frac{a_{\max }^2-\sqrt{a_{\max }^4-8J_{\max }^2{S}_{i+1}}}{2J_{\max }}---\left(17\right)$

$V_{i,T\_l}=3\sqrt{J_{\max }{S}_{i+1}^2}---\left(18\right)$

The present invention compared with prior art has the following advantages and effect:

(1) will be based on the path of adjacent two sections tracks of S curve acceleration and deceleration control as constraint condition

Comprise based on the path length constraint condition of the leading portion track in adjacent two sections tracks of S curve acceleration and deceleration control with based on the path length constraint condition of the back segment track in adjacent two sections tracks of S curve acceleration and deceleration control based on the path length constraint condition of adjacent two sections tracks of S curve acceleration and deceleration control, make that being connected an actual feed at place at adjacent two sections tracks can arrive precalculated speed, linking speed between adjacent two sections orbit segments can not produce sudden change, be to link up smoothly between adjacent two sections orbit segments, make the numerical control device machining locus continuous, rate smoothing, and when part processing is finished, tool speed can in time drop to zero, prevents from that cutter from crossing to cut.

(2) improve digital control system acceleration and deceleration control efficient

This disposal route can guarantee that S curve acceleration and deceleration control input parameter is reasonable, and digital control system does not need to thresh last spot speed accessibility judgement and adjustment when doing S curve acceleration and deceleration control, thereby improves digital control system acceleration and deceleration control efficient.

(3) have wide range of applications

This disposal route also can be applied to nurbs curve subsection interpolation algorithm, improves the pre-service efficient of the prediction pretreatment module in the nurbs curve subsection interpolation algorithm.

Description of drawings

Fig. 1 is the intersegmental linking velocity process of a continuous path of the present invention method overview flow chart

Fig. 2 (a) is that straight path and straight path are connected the model synoptic diagram

Fig. 2 (b) is that straight path and arc track are connected the model synoptic diagram

Fig. 2 (c) is that arc track and straight path are connected the model synoptic diagram

Fig. 2 (d) is that arc track and arc track are connected the model synoptic diagram

Fig. 3 is the path calculation flow chart

Fig. 4 is the speed calculation process flow diagram of the linking point of the adjacent two sections tracks under acceleration, bow high level error, instruction speed of feed and turning constraint condition

Embodiment

The invention will be further described below in conjunction with accompanying drawing.

Shown in the intersegmental linking velocity process of accompanying drawing 1 continuous path of the present invention method overview flow chart, digital control system in the numerical control device is deciphered processing to the numerical control program in machine code, and store decode results into the decoding buffer zone, utilize the program segment information of deciphering in the buffer zone to the intersegmental linking velocity process of continuous path to be processed, the intersegmental linking velocity process of described continuous path may further comprise the steps:

(1) determines that adjacent two sections tracks are connected model, and obtain the kinematic parameter of adjacent two sections tracks to be processed;

Adjacent two sections tracks of the present invention are connected model and comprise following four kinds: straight path shown in the accompanying drawing 2 (a) and straight path are connected model; Straight path shown in the accompanying drawing 2 (b) and arc track are connected model; Arc track shown in the accompanying drawing 2 (c) and straight path are connected model; Arc track shown in the accompanying drawing 2 (d) and arc track are connected model.After determining that pending adjacent two sections tracks are connected model, obtain the kinematic parameter of adjacent two sections tracks to be processed, kinematic parameter of the present invention comprises the path of instruction speed of feed, track.

Repeating step (1), all program segments dispose in the decoding buffer zone.

(2) calculate the path of adjacent two sections tracks to be processed, the calculation procedure flow process as shown in Figure 3;

When i section track is a straight-line segment,

$S_i=\sqrt{{(x_{i+1}-x_i)}^2+{(y_{i+1}-y_i)}^2}---\left(1\right)$

Wherein: i=1,2,3...N, N represent orbit segment number to be processed; (x _i, y _i) be i section Track Initiation point coordinate; (x _I+1, y _I+1) be i section track end point coordinate;

When i section track is an arc section, circular arc path length calculation step comprises: (2.1) calculate the positive dirction angle in the horizontal axis of circular arc initial point place principal normal unit vector and workpiece coordinate system, (2.2) calculating is at the positive dirction angle of the horizontal axis of circular arc end point place's principal normal unit vector and workpiece coordinate system, and (2.3) calculate circular arc path length;

(2.1) calculate in circular arc initial point place principal normal unit vector

Positive dirction angle α with the horizontal axis of workpiece coordinate system _{I_s}:

$\sin {\mathrm{\&alpha;}}_{i\_s}=\frac{y_{i\_c}-y_i}{R_i}---\left(2\right)$

$\cos {\mathrm{\&alpha;}}_{i\_s}=\frac{x_{i\_c}-x_i}{R_i}---\left(3\right)$

Wherein: i=1,2,3...N, N represent orbit segment number to be processed; (x _i, y _i) be i section Track Initiation point coordinate; (x _{I_c}, y _{I_c}) be the central coordinate of circle of circular arc when i section track is circular arc; R _iBe the radius of circular arc when i section track is circular arc, get α by formula (2) and (3) _{I_s}Computing formula be:

(2.2) calculate principal normal unit vector at some place, circular arc end

Positive dirction angle α with the horizontal axis of workpiece coordinate system _{I_e}:

$\sin {\mathrm{\&alpha;}}_{i\_e}=\frac{y_{i\_c}-y_{i+1}}{R_i}---\left(5\right)$

$\cos {\mathrm{\&alpha;}}_{i\_e}=\frac{x_{i\_c}-x_{i+1}}{R_i}---\left(6\right)$

Wherein: (x _I+1, y _I+1) be i section track end point coordinate;

Get α by formula (5) and (6) _{I_e}Computing formula be:

(2.3) calculate circular arc path length S _i:

Get S by formula (4) and (7) _iComputing formula be:

Repeating step (2), all program segments dispose in the decoding buffer zone.

(3) the speed V of the linking point of the adjacent two section tracks of calculating under acceleration, bow high level error, instruction speed of feed and turning constraint condition _{I, T}, calculation process as shown in Figure 4;

(3.1) calculating is in the unit vector of Track Initiation point place tangent line Sine value sin θ with the positive dirction angle of the horizontal axis of workpiece coordinate system _{I_s}With cosine value cos θ _{I_s}

When i section track is a straight-line segment, shown in accompanying drawing 2 (a) and accompanying drawing 2 (b),

$\cos {\mathrm{\&theta;}}_{i\_s}=\frac{y_i}{S_i}---\left(9\right)$

$\sin {\mathrm{\&theta;}}_{i\_s}=\frac{x_i}{S_i}---\left(10\right)$

When i section track is an arc section, shown in accompanying drawing 2 (c) and accompanying drawing 2 (d),

Wherein: θ _{I_s}Be unit vector at Track Initiation point place tangent line

Positive dirction angle with the horizontal axis of workpiece coordinate system; (x _{I_c}, y _{I_c}) be the central coordinate of circle of circular arc; R _iArc radius for circular arc;

(3.2) calculating is in the unit vector of some place, track end tangent line

Sine value sin θ with the positive dirction angle of the horizontal axis of workpiece coordinate system _{I_e}With cosine value cos θ _{I_e}

When i section track is a straight-line segment, shown in accompanying drawing 2 (a) and accompanying drawing 2 (b),

$\cos {\mathrm{\&theta;}}_{i\_e}=\frac{y_{i+1}}{S_i}---\left(13\right)$

$\sin {\mathrm{\&theta;}}_{i\_e}=\frac{x_{i+1}}{S_i}---\left(14\right)$

When i section track is an arc section, shown in accompanying drawing 2 (c) and accompanying drawing 2 (d),

$\sin {\mathrm{\&theta;}}_{i\_e}=\frac{y_{i\_c}-y_{i+1}}{R_i}---\left(15\right)$

Wherein: θ _{I_e}Be unit vector at some place, track end tangent line

Positive dirction angle with the horizontal axis of workpiece coordinate system

(3.3) the linking contact speed of calculating under acceleration and the adjacent two sections track angles constraint is V _{I, A}

$V_{i,A}=\min \{\frac{a_{\max \_x}T}{|\cos {\mathrm{\&theta;}}_{i+1\_s}-\cos {\mathrm{\&theta;}}_{i\_e}|},\frac{a_{\max \_y}T}{|\sin {\mathrm{\&theta;}}_{i+1\_s}-\sin {\mathrm{\&theta;}}_{i\_e}|}\}---\left(17\right)$

Wherein: a _{Max_x}Be digital control system x axle acceleration; a _{Max_y}Be digital control system y axle acceleration; T is the sampling period; θ _{I+1_s}Be unit vector at Track Initiation point place tangent line

Positive dirction angle with the horizontal axis of workpiece coordinate system;

(3.4) the linking contact speed of calculating under the constraint of bow high level error is V _{I, G}

$V_{i,G}=\min \{\sqrt{\frac{8R_{i}E}{T}},\sqrt{\frac{8R_{i+1}E}{T}}\}---\left(18\right)$

Wherein: E is the bow high level error that system allows

(3.5) get V _{I, A}, V _{I, G}, i section track instruction speed of feed V _{I, F}With i+1 section track instruction speed of feed V _{I+1, F}Four minimum value is as the speed V of the linking point of the adjacent two sections tracks under acceleration, bow high level error, instruction speed of feed and turning constraint condition _{I, T}, promptly have:

V _i，T＝min{V _i，A，V _i，G，V _i，F，V _i+1，F}(19)

(4) calculate to satisfy speed based on the linking point of adjacent two sections tracks of the path length constraint condition of the leading portion track in adjacent two sections tracks of S curve acceleration and deceleration control;

Described path length constraint condition based on the leading portion track in adjacent two sections tracks of S curve acceleration and deceleration control is inequality group (20), (21) and (22):

$\left\{\begin{array}{c}|V_{i,T}-V_{i\_s}|\&GreaterEqual;\frac{a_{\max }^2}{J_{\max }}\\ S_i>2V_{i\_s}\frac{a_{\max }}{J_{\max }}+\frac{a_{\max }^3}{J_{\max }^2}\\ S_i<\frac{J_{\max }(V_{i,T}^2-V_{i\_s}^2)+a_{\max }^2(V_{i,T}+V_{i\_s})}{2J_{\max }{a}_{\max }}\end{array}\right.---\left(20\right)$

$\left\{\begin{array}{c}|V_{i,T}-V_{i\_s}|<\frac{a_{\max }^2}{J_{\max }}\\ S_i<(V_{i,T}+V_{i\_s})\sqrt{\frac{|V_{i,T}-V_{i\_s}|}{J_{\max }}}\end{array}\right.---\left(21\right)$

$\left\{\begin{array}{c}|V_{i,T}-V_{i\_s}|\&GreaterEqual;\frac{a_{\max }^2}{J_{\max }}\\ S_i\&le;{2V}_{i\_s}\frac{a_{\max }}{J_{\max }}+\frac{a_{\max }^3}{J_{\max }^2}\end{array}\right.---\left(22\right)$

Wherein: V _{I_s}Be the initial point speed of i section track; a _MaxPeak acceleration for the digital control system permission; J _MaxMaximum acceleration for the digital control system permission; S _iIt is the path of i section track; V _{I, T}Speed for the linking point of adjacent two sections tracks of under acceleration, bow high level error, instruction speed of feed and turning constraint condition, calculating;

When inequality group (20), (21) and (22) when all being false, the speed V of the linking point of the adjacent two sections tracks that calculate is described under acceleration, bow high level error, instruction speed of feed and turning constraint condition _{I, T}Can satisfy path length constraint condition, satisfy speed V based on the linking point of adjacent two sections tracks of the path length constraint condition of the leading portion track in adjacent two sections tracks of S curve acceleration and deceleration control based on the leading portion track in adjacent two sections tracks of S curve acceleration and deceleration control _{I, T_f}Equal V _{I, T}

When inequality group (20), (21) and (22) by and only form immediately by one, the speed V of the linking point of the adjacent two sections tracks that calculate under acceleration, bow high level error, instruction speed of feed and turning constraint condition is described _{I, T}Can not satisfy path length constraint condition, satisfy speed V based on the linking point of adjacent two sections tracks of the path length constraint of the leading portion track in adjacent two sections tracks of S curve acceleration and deceleration control based on the leading portion track in adjacent two sections tracks of S curve acceleration and deceleration control _{I, T_f}Computing method are: when inequality group (20) is set up, and V _{I, T_f}Calculate according to formula (23); When inequality group (21) or (22) establishment, V _{I, T_f}Calculate according to formula (24) and (25);

$V_{i,T\_f}=\frac{\sqrt{a_{\max }^4-4J_{\max }(a_{\max }^2{V}_{i\_s}-J_{\max }{V}_{i\_s}^2-2J_{\max }{a}_{\max }{S}_i)}-a_{\mathrm{<figure-callout\; id="2"\; label="max"\; filenames="HSA00000439941900031.png"\; state="\{\{state\}\}">max</figure-callout>}}^2}{2J_{\max }}---\left(23\right)$

$V_{i,T\_f}=V_{i\_s}+J_{\max }{T}_{\mathrm{jerk}}^2---\left(24\right)$

$J_{\max }{T}_{\mathrm{jerk}}^3+2V_{i,T\_f}-S_i=0---\left(25\right)$

Wherein: T _JerkFor adding the time of accelerating sections;

(5) calculate to satisfy speed based on the linking point of adjacent two sections tracks of the path length constraint condition of the back segment track in adjacent two sections tracks of S curve acceleration and deceleration control, and as the end value of linking speed between adjacent two sections orbit segments.

Described path length constraint condition based on the back segment track in adjacent two sections tracks of S curve acceleration and deceleration control is inequality group (26), (27) and (28):

$\left\{\begin{array}{c}{V}_{i,T\_f}\&GreaterEqual;\frac{a_{\max }^2}{J_{\max }}\\ S_{i+1}>2V_{i,T\_f}\frac{a_{\max }}{J_{\max }}+\frac{a_{\max }^3}{J_{\max }^2}\\ S_{i+1}<\frac{a_{\max }^2{V}_{i,T\_f}-J_{\max }{V}_{i,T\_\mathrm{<figure-callout\; id="2"\; label="f"\; filenames="HSA00000439941900031.png"\; state="\{\{state\}\}">f</figure-callout>}}^2}{2J_{\max }{a}_{\max }}\end{array}\right.---\left(26\right)$

$\left\{\begin{array}{c}{V}_{i,T\_f}<\frac{a_{\max }^2}{J_{\max }}\\ S_{i+1}<V_{i,T\_f}\sqrt{\frac{V_{i,T\_f}}{J_{\max }}}\end{array}\right.---\left(27\right)$

$\left\{\begin{array}{c}{V}_{i,T\_f}\&GreaterEqual;\frac{a_{\max }^2}{J_{\max }}\\ S_{i+1}\&le;{2V}_{i,T\_f}\frac{a_{\max }}{J_{\max }}+\frac{a_{\max }^3}{J_{\max }^2}\end{array}\right.---\left(28\right)$

Wherein: S _I+1It is the path of i+1 section track; V _{I, T_f}For satisfying speed based on the linking point of adjacent two sections tracks of the path length constraint condition of the leading portion track in adjacent two sections tracks of S curve acceleration and deceleration control;

When (26), (27) and (28) when all being false, the speed V that satisfies based on the linking point of adjacent two sections tracks of the path length constraint condition of the leading portion track in adjacent two sections tracks of S curve acceleration and deceleration control is described _{I, T_f}Can satisfy path length constraint condition, satisfy speed V based on the linking point of adjacent two sections tracks of the path length constraint condition of the back segment track in adjacent two sections tracks of S curve acceleration and deceleration control based on the back segment track in adjacent two sections tracks of S curve acceleration and deceleration control _{I, T_l}Equal V _{I, T_f}

When inequality group (26), (27) and (28) by and only form immediately by one, the speed V that satisfies based on the linking point of the path length constraint condition of the leading portion track in adjacent two sections tracks of S curve acceleration and deceleration control is described _{I, T_f}Can not satisfy path length constraint condition, satisfy speed V based on the linking point of adjacent two sections tracks of the path length constraint condition of the back segment track in adjacent two sections tracks of S curve acceleration and deceleration control based on the back segment track in adjacent two sections tracks of S curve acceleration and deceleration control _{I, T_l}Computing method are: when inequality group (26) is set up, and V _{I, T_l}Calculate according to formula (29); When inequality group (27) or (28) establishment, V _{I, T_l}Calculate according to formula formula (30);

$V_{i,T\_l}=\frac{a_{\max }^2-\sqrt{a_{\max }^4-8J_{\max }^2{S}_{i+1}}}{2J_{\max }}---\left(29\right)$

$V_{i,T\_l}=3\sqrt{J_{\max }{S}_{i+1}^2}---\left(30\right)$

Repeating step (3) is to (5), and all program segments dispose in the decoding buffer zone.

Explanation is that a kind of intersegmental linking velocity process of continuous path method that is used for digital control system of the present invention is not limited to the foregoing description at last, can also make various modifications, conversion and distortion.Therefore, instructions and accompanying drawing are regarded in an illustrative, rather than a restrictive.Every foundation technical scheme of the present invention is made amendment, modification or equivalent variations, and does not break away from the thought and the scope of technical solution of the present invention, and it all should be encompassed in the middle of the claim scope of the present invention.

Claims (4)

1. the intersegmental linking velocity process of continuous path method that is used for digital control system, digital control system in the numerical control device is deciphered processing to the numerical control program in machine code, and store decode results into the decoding buffer zone, it is characterized in that, utilize the program segment information of deciphering in the buffer zone to the intersegmental linking velocity process of continuous path to be processed, make that the numerical control device machining locus is continuous, rate smoothing, the intersegmental linking velocity process of described continuous path method may further comprise the steps:

(1) determines that adjacent two sections tracks are connected model, and obtain the kinematic parameter of adjacent two sections tracks to be processed;

(2) calculate the path of adjacent two sections tracks to be processed;

(3) speed of the linking point of the adjacent two section tracks of calculating under acceleration, bow high level error, instruction speed of feed and turning constraint condition;

(4) calculate to satisfy speed based on the linking point of adjacent two sections tracks of the path length constraint condition of the leading portion track in adjacent two sections tracks of S curve acceleration and deceleration control;

(5) calculate to satisfy speed based on the linking point of adjacent two sections tracks of the path length constraint condition of the back segment track in adjacent two sections tracks of S curve acceleration and deceleration control, and as the end value of linking speed between adjacent two sections orbit segments.

2. a kind of intersegmental linking velocity process of continuous path method that is used for digital control system according to claim 1 is characterized in that, the path of described adjacent two sections tracks to be processed comprises straight line path length and circular arc path length; Described circular arc path length calculation step comprises: (2.1) calculate the positive dirction angle in the horizontal axis of circular arc initial point place principal normal unit vector and workpiece coordinate system, (2.2) calculating is at the positive dirction angle of the horizontal axis of circular arc end point place's principal normal unit vector and workpiece coordinate system, and (2.3) calculate circular arc path length;

(2.1) calculate in circular arc initial point place principal normal unit vector

Positive dirction angle α with the horizontal axis of workpiece coordinate system _{I_s}:

Wherein: i=1,2,3...N, N represent orbit segment number to be processed; (x _i, y _i) be i section Track Initiation point coordinate; (x _{I_c}, y _{I_c}) be the central coordinate of circle of circular arc when i section track is circular arc; R _iBe the radius of circular arc when i section track is circular arc, get α by formula (1) and (2) _{I_s}Computing formula be:

(2.2) calculate principal normal unit vector at some place, circular arc end

Positive dirction angle α with the horizontal axis of workpiece coordinate system _{I_e}:

Wherein: (x _I+1, y _I+1) be i section track end point coordinate;

Get α by formula (4) and (5) _{I_e}Computing formula be:

(2.3) calculate circular arc path length S _i:

Get S by formula (3) and (6) _iComputing formula be:

3. a kind of intersegmental linking velocity process of continuous path method that is used for digital control system according to claim 1, it is characterized in that described path length constraint condition based on the leading portion track in adjacent two sections tracks of S curve acceleration and deceleration control is inequality group (8), (9) and (10):

Wherein: V _{I_s}Be the initial point speed of i section track; a _MaxPeak acceleration for the digital control system permission; J _MaxMaximum acceleration for the digital control system permission; S ' _iIt is the path of i section track; V _{I, T}Speed for the linking point of adjacent two sections tracks of under acceleration, bow high level error, instruction speed of feed and turning constraint condition, calculating;

When inequality group (8), (9) and (10) when all being false, the speed V of the linking point of the adjacent two sections tracks that calculate is described under acceleration, bow high level error, instruction speed of feed and turning constraint condition _{I, T}Can satisfy path length constraint condition, satisfy speed V based on the linking point of adjacent two sections tracks of the path length constraint condition of the leading portion track in adjacent two sections tracks of S curve acceleration and deceleration control based on the leading portion track in adjacent two sections tracks of S curve acceleration and deceleration control _{I, T_f}Equal V _{I, T}

When inequality group (8), (9) and (10) by and only form immediately by one, the speed V of the linking point of the adjacent two sections tracks that calculate under acceleration, bow high level error, instruction speed of feed and turning constraint condition is described _{I, T}Can not satisfy path length constraint condition, satisfy speed V based on the linking point of adjacent two sections tracks of the path length constraint of the leading portion track in adjacent two sections tracks of S curve acceleration and deceleration control based on the leading portion track in adjacent two sections tracks of S curve acceleration and deceleration control _{I, T_f}Computing method are: when inequality group (8) is set up, and V _{I, T_f}Calculate according to formula (11); When inequality group (9) or (10) establishment, V _{I, T_f}Calculate according to formula (12) and (13);

Wherein: T _JerkFor adding the time of accelerating sections.

4. a kind of intersegmental linking velocity process of continuous path method that is used for digital control system according to claim 1, it is characterized in that described path length constraint condition based on the back segment track in adjacent two sections tracks of S curve acceleration and deceleration control is inequality group (14), (15) and (16):

Wherein: S _I+1It is the path of i+1 section track; V _{I, T_f}For satisfying speed based on the linking point of adjacent two sections tracks of the path length constraint condition of the leading portion track in adjacent two sections tracks of S curve acceleration and deceleration control;

When (14), (15) and (16) when all being false, the speed V that satisfies based on the linking point of adjacent two sections tracks of the path length constraint condition of the leading portion track in adjacent two sections tracks of S curve acceleration and deceleration control is described _{I, T_f}Can satisfy path length constraint condition, satisfy speed V based on the linking point of adjacent two sections tracks of the path length constraint condition of the back segment track in adjacent two sections tracks of S curve acceleration and deceleration control based on the back segment track in adjacent two sections tracks of S curve acceleration and deceleration control _{I, T_f}Equal V _{I, T_f}

When inequality group (14), (15) and (16) by and only form immediately by one, the speed V that satisfies based on the linking point of the path length constraint condition of the leading portion track in adjacent two sections tracks of S curve acceleration and deceleration control is described _{I, T_f}Can not satisfy path length constraint condition, satisfy speed V based on the linking point of adjacent two sections tracks of the path length constraint condition of the back segment track in adjacent two sections tracks of S curve acceleration and deceleration control based on the back segment track in adjacent two sections tracks of S curve acceleration and deceleration control _{I, T_f}Computing method are: when inequality group (14) is set up, and V _{I, T_f}Calculate according to formula (17); When inequality group (15) or (16) establishment, V _{I, T_f}Calculate according to formula formula (18);

Images