function [swashCtrlIdeal, swashCtrlTable,ax_sw] = cvtCalcSwashControl(... tgtVSpdRanges,rWhl,nGearCVTOut,nDiff,nFinalDrive,wEng,wPumpNom,... nHSPumpMotor,tgtMaxSwash,nTRing,nTSuns,nGearHSOut,pumpVolEff,showplot,varargin) % Calculates the table for controlling the hydrostatic pump % displacement based on target vehicle speed. % % tgtVSpdRanges Target vehicle speed ranges for transmission (km/h) % rWhl Radius of wheel (m) % nGearCVTOut Gear ratio after CVT output % nDiff Ratio of differential % nFinalDrive Ratio of wheel hub planetary gear % wEng Engine target speed % wPumpNom Pump nominal speed % nHSPumpMotor Ratio (Hydrostatic Pump Displacement/ % Hydrostatic Motor Displacement) % tgtMaxSwash Target max displacement ratio of pump swash plate (0-1) % nTRing Number of teeth on planetary ring gears (all) % nTSuns Vector 1x4 number of teeth on sun gear for each planetary % nGearHSOut Gear ratio at output of hydrostatic transmission % pumpVolEff Hydrostatic pump volumetric efficiency % showplot Set to 'plot' to plot swash control table % Copyright 2023-2026 The MathWorks, Inc. %% Calculate ratio (CVT output shaft/Vehicle Speed) (rpm/kmph) vWhl2CVTOut = 1/(3.6*rWhl*pi/30)*nGearCVTOut*nDiff*nFinalDrive; %% Obtain design % Get ratio wSun-to-wCVT Out when engine is not spinning % Use this to calculate slope for intersection points nSun1CVTOut_e0s1 = cvtGetCVTOutputSpeeds(0,1,nTRing,nTSuns); slopeCVTCtrl = nSun1CVTOut_e0s1*... (nHSPumpMotor)*1/(nGearHSOut)*wPumpNom/wEng; % Get ratio wEng-to-wCVT_Out when swash is 0 % Use to obtain midpoint of each speed segment nEng2CVTOut_Sw0 = cvtGetCVTOutputSpeeds(1,0,nTRing,nTSuns); % Convert desired vehicle speed ranges to ratio wEng-to-CVT Output speed tgtCVTRatios = tgtVSpdRanges*vWhl2CVTOut/wEng; % Assemble speed segment lines for i = 1:length(nEng2CVTOut_Sw0) ratioSeg(i,2) = nEng2CVTOut_Sw0(i); % Midpoint ratioSeg(i,1) = nEng2CVTOut_Sw0(i)-slopeCVTCtrl(i); % Lower ratio ratioSeg(i,3) = nEng2CVTOut_Sw0(i)+slopeCVTCtrl(i); % Higher ratio end % Find points of intersection swas0 = -nEng2CVTOut_Sw0(1)/slopeCVTCtrl(1); cvtr0 = nEng2CVTOut_Sw0(1)+slopeCVTCtrl(1)*swas0; for i = 1:(length(nEng2CVTOut_Sw0)-1) swas(i) = (nEng2CVTOut_Sw0(i+1)-nEng2CVTOut_Sw0(i))/... (slopeCVTCtrl(i)-slopeCVTCtrl(i+1)); cvtr(i) = nEng2CVTOut_Sw0(i)+slopeCVTCtrl(i)*swas(i); end swas5 = (tgtCVTRatios(end)-nEng2CVTOut_Sw0(end))/slopeCVTCtrl(end); cvtr5 = nEng2CVTOut_Sw0(end)+swas5*slopeCVTCtrl(end); % Assemble ideal values into table swasPts = [swas0 swas swas5]; cvtrPts = [cvtr0 cvtr cvtr5]; swashCtrlIdeal = [swasPts' cvtrPts']; %% Calculate Table % To smooth transitions and account for volumetric efficiency, % and add offsets at transitions. yOff = 5e-5; swashCtrlTable = [swashCtrlIdeal(1,:);... 0 nEng2CVTOut_Sw0(1);... swashCtrlIdeal(2,1)/pumpVolEff swashCtrlIdeal(2,2)-yOff;... swashCtrlIdeal(2,1)*pumpVolEff swashCtrlIdeal(2,2)+yOff;... 0 nEng2CVTOut_Sw0(2);... swashCtrlIdeal(3,1)/pumpVolEff swashCtrlIdeal(3,2)-yOff;... swashCtrlIdeal(3,1)*pumpVolEff swashCtrlIdeal(3,2)+yOff;... 0 nEng2CVTOut_Sw0(3);... swashCtrlIdeal(4,1)/pumpVolEff swashCtrlIdeal(4,2)-yOff;... swashCtrlIdeal(4,1)*pumpVolEff swashCtrlIdeal(4,2)+yOff;... 0 nEng2CVTOut_Sw0(4);... swashCtrlIdeal(5,:)]; if(strcmpi(showplot,'plot')) if(nargin==14) % Reuse figure if it exists, else create new figure figString = 'h1_CVT_Ratios'; % Only create a figure if no figure exists figExist = 0; fig_hExist = evalin('base',['exist(''' figString ''')']); if (fig_hExist) figExist = evalin('base',['ishandle(' figString ') && strcmp(get(' figString ', ''type''), ''figure'')']); end if ~figExist fig_h = figure('Name',figString); assignin('base',figString,fig_h); else fig_h = evalin('base',figString); end figure(fig_h) clf(fig_h) ax_sw = gca; elseif(nargin==15) ax_sw = varargin{1}; % Use axis handle if provided cla(ax_sw) end ax_sw.XAxisLocation = 'origin'; ax_sw.YAxisLocation = 'origin'; %% Plot desired corners of swash plate control l_h(1) = plot(ax_sw,[-1 1 -1 1 -1]*tgtMaxSwash,tgtCVTRatios*wEng/vWhl2CVTOut,'r',... 'Marker','square','MarkerSize',12, 'MarkerFaceColor',[1 0.8 0.8],... 'DisplayName','Target','Tag','Target'); hold(ax_sw,'on'); hold(ax_sw,'off'); hold(ax_sw,'on'); l_h(2) = plot(ax_sw,swasPts,cvtrPts*wEng/vWhl2CVTOut,'b-o','LineWidth',2,... 'DisplayName','Control Map','Tag','Control'); for i = 1:size(ratioSeg,1) l_h(3) = plot(ax_sw,[-1 0 1],ratioSeg(i,:)*wEng/vWhl2CVTOut,'--o','Color',[0.6 0.6 0.6],... 'DisplayName','Possible','Tag','Possible'); end hold(ax_sw,'off'); ax_sw.YAxisLocation = 'origin'; axXLims = get(ax_sw,'XLim'); set(ax_sw,'XLim',[-1 1]*max([abs(axXLims) 1.1])); maxy = max([cvtrPts max(ratioSeg,[],'all') tgtCVTRatios]); set(ax_sw,'YLim',[0 maxy]*wEng/vWhl2CVTOut*1.1); patch(ax_sw,[-1 -[1 1]*max([abs(axXLims) 1.1]) -1],[0 0 1 1]*38,[1 1 1]*0.6,'FaceAlpha',0.3,'EdgeColor','none'); patch(ax_sw,[ 1 [1 1]*max([abs(axXLims) 1.1]) 1],[0 0 1 1]*38,[1 1 1]*0.6,'FaceAlpha',0.3,'EdgeColor','none'); ylabel(ax_sw,'Vehicle Speed (km/h)') xlabel(ax_sw,'Displacement Ratio Hydrostatic Pump (0-1)') title(ax_sw,'Swash Plate Ratio by Speed Range') legend(ax_sw,l_h,'Location','West') box(ax_sw,'on') if(nargin<15) sm_cvt_power_split_pg_4range_animate_format(ax_sw); end end