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<blockquote data-quote="harm lok" data-source="post: 1089909" data-attributes="member: 415123">This is copy of the livescript i have programmed in Matlab.&nbsp; It&nbsp; is not just a complete algorithm in one equation , but a step by step approach so everyone could understand and use this method for custom situations.I have tested the script with my own channelmaster 1.2m offset dish with a 18 Inch actuator.I have also programmed an animated plot so also the moves off the actuator and dish are visualised. &nbsp;I will publish it here when i have converted it to an image that can published at this blog.[ATTACH=full]130894[/ATTACH]Matlab livescript----------------------------------------------------------------------------------------------Defining the dish variablesRadius = 370;The radius between dish pivot and the actuator pivot point on the dish lever (mm)DishpivotOffset = 190;The length between dish pivot and the pivot of the actuator mount. (mm)ActuatorOffset = 48;Length between actuator pivot point and the centre of the actuator mount. (mm)MinActuatorLength = 210;MaxActuatorLength = 550;Minimal en maximum actuator extensions. (mm)ActPivToRadiusMin = sqrt( ( (ActuatorOffset^2) + (MinActuatorLength^2) ) ) ;ActPivToRadiusMax = sqrt( ( (ActuatorOffset^2) + (MaxActuatorLength^2) ) ) ;Calculate the distances between the actuator pivot and the actuator pivot on the disk lever for the minimal and maximum actuator lengt.&nbsp; (Pythagorean theorem)Pact = [ 0 ; 0&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;&nbsp; ];Pdsh = [ 0 ; DishpivotOffset ];Ract = ActPivToRadiusMin ;Rdsh = Radius&nbsp;&nbsp; ;Definition off the coordinates for both virtual circles of the actuator and the dish.&nbsp; This the definition of the virtual circles for minimal extended actuator. Given is a virtual circle with a center point M (a, b) and a radius r.&nbsp; So for every point on the virtual circle i have used midpoint equations :[ATTACH=full]130896[/ATTACH]&nbsp;D2 = sum((Pact-Pdsh).^2);&nbsp;&nbsp; P0 = (Pdsh+Pact)/2+(Rdsh^2-Ract^2)/D2/2*(Pact-Pdsh);&nbsp;&nbsp; t = ((Rdsh+Ract)^2-D2)*(D2-(Ract-Rdsh)^2);&nbsp;&nbsp; if t &lt;= 0&nbsp; &nbsp;&nbsp; fprintf('The circles don''t intersect : initial values not correct.\n')&nbsp;&nbsp; else&nbsp; &nbsp;&nbsp; T = sqrt(t)/D2/2*[0 -1;1 0]*(Pact-Pdsh);&nbsp; &nbsp;&nbsp; Pa = P0 + T;&nbsp; &nbsp;&nbsp; Pb = P0 - T;&nbsp;&nbsp; endThe virtual circles are defined as a collecting of points based on a rotating triangle. I have used the pivot of the actuator as coordinate&nbsp; [ 0 , 0] Pa and Pb are circles' intersection points . We only need the value Pb. Pa is the other intersection point which as not important for our calculation.Pa = Coordinate of the minimal extended actuator .Pact = [ 0 ; 0&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;&nbsp; ];Pdsh = [ 0 ; DishpivotOffset ];Ract = MaxActuatorLength ;Rdsh = Radius&nbsp;&nbsp; ;Definition off the coordinates for both virtual circles of the actuator and the dish.&nbsp; This the definition of the virtual circles for minimal extended actuator&nbsp;D2 = sum((Pact-Pdsh).^2);&nbsp;&nbsp; P0 = (Pdsh+Pact)/2+(Rdsh^2-Ract^2)/D2/2*(Pact-Pdsh);&nbsp;&nbsp; t = ((Rdsh+Ract)^2-D2)*(D2-(Ract-Rdsh)^2);&nbsp;&nbsp; if t &lt;= 0&nbsp; &nbsp;&nbsp; fprintf('The circles don''t intersect : initial values not correct.\n')&nbsp;&nbsp; else&nbsp; &nbsp;&nbsp; T = sqrt(t)/D2/2*[0 -1;1 0]*(Pact-Pdsh);&nbsp; &nbsp;&nbsp; Pc = P0 + T;&nbsp; &nbsp;&nbsp; Pd = P0 - T;&nbsp;&nbsp; endPc and Pd are circles' intersection points . We only need the value Pd. Pc is the other intersection point which as not important for our calculation.Pc = Coordinate of the maximal extended actuator .&nbsp; Angle = sin (Pb(2) / (DishpivotOffset - Pb(1) ) ) ;&nbsp; MinAngledegree = Angle / (pi/180);&nbsp; EastlimitAngle = 90 + MinAngledegree&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;&nbsp; &nbsp; EastlimitAngle = 67.2740&nbsp; Angle = sin (Pd(2) / (DishpivotOffset - Pd(1) ) ) ;&nbsp; MaxAngledegree = (Angle / (pi/180) );&nbsp; WestlimitAngle = ( 90 +&nbsp; MaxAngledegree&nbsp; ) -&nbsp; EastlimitAngle&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; WestlimitAngle = 80.0125Please post reactions or comment .If someone wanted the Matlab file send me a personal message.It also possible to copy / paste this script (only remove the results)</blockquote>

[QUOTE="harm lok, post: 1089909, member: 415123"] This is copy of the livescript i have programmed in Matlab. It is not just a complete algorithm in one equation , but a step by step approach so everyone could understand and use this method for custom situations. I have tested the script with my own channelmaster 1.2m offset dish with a 18 Inch actuator. I have also programmed an animated plot so also the moves off the actuator and dish are visualised. I will publish it here when i have converted it to an image that can published at this blog. [ATTACH type="full"]130894[/ATTACH] Matlab livescript ---------------------------------------------------------------------------------------------- Defining the dish variables Radius = 370; The radius between dish pivot and the actuator pivot point on the dish lever (mm) DishpivotOffset = 190; The length between dish pivot and the pivot of the actuator mount. (mm) ActuatorOffset = 48; Length between actuator pivot point and the centre of the actuator mount. (mm) MinActuatorLength = 210; MaxActuatorLength = 550; Minimal en maximum actuator extensions. (mm) ActPivToRadiusMin = sqrt( ( (ActuatorOffset^2) + (MinActuatorLength^2) ) ) ; ActPivToRadiusMax = sqrt( ( (ActuatorOffset^2) + (MaxActuatorLength^2) ) ) ; Calculate the distances between the actuator pivot and the actuator pivot on the disk lever for the minimal and maximum actuator lengt. (Pythagorean theorem) Pact = [ 0 ; 0 ]; Pdsh = [ 0 ; DishpivotOffset ]; Ract = ActPivToRadiusMin ; Rdsh = Radius ; Definition off the coordinates for both virtual circles of the actuator and the dish. This the definition of the virtual circles for minimal extended actuator. Given is a virtual circle with a center point M (a, b) and a radius r. So for every point on the virtual circle i have used midpoint equations : [ATTACH type="full"]130896[/ATTACH] D2 = sum((Pact-Pdsh).^2); P0 = (Pdsh+Pact)/2+(Rdsh^2-Ract^2)/D2/2*(Pact-Pdsh); t = ((Rdsh+Ract)^2-D2)*(D2-(Ract-Rdsh)^2); if t <= 0 fprintf('The circles don''t intersect : initial values not correct.\n') else T = sqrt(t)/D2/2*[0 -1;1 0]*(Pact-Pdsh); Pa = P0 + T; Pb = P0 - T; end The virtual circles are defined as a collecting of points based on a rotating triangle. I have used the pivot of the actuator as coordinate [ 0 , 0] Pa and Pb are circles' intersection points . We only need the value Pb. Pa is the other intersection point which as not important for our calculation. Pa = Coordinate of the minimal extended actuator . Pact = [ 0 ; 0 ]; Pdsh = [ 0 ; DishpivotOffset ]; Ract = MaxActuatorLength ; Rdsh = Radius ; Definition off the coordinates for both virtual circles of the actuator and the dish. This the definition of the virtual circles for minimal extended actuator D2 = sum((Pact-Pdsh).^2); P0 = (Pdsh+Pact)/2+(Rdsh^2-Ract^2)/D2/2*(Pact-Pdsh); t = ((Rdsh+Ract)^2-D2)*(D2-(Ract-Rdsh)^2); if t <= 0 fprintf('The circles don''t intersect : initial values not correct.\n') else T = sqrt(t)/D2/2*[0 -1;1 0]*(Pact-Pdsh); Pc = P0 + T; Pd = P0 - T; end Pc and Pd are circles' intersection points . We only need the value Pd. Pc is the other intersection point which as not important for our calculation. Pc = Coordinate of the maximal extended actuator . Angle = sin (Pb(2) / (DishpivotOffset - Pb(1) ) ) ; MinAngledegree = Angle / (pi/180); EastlimitAngle = 90 + MinAngledegree [I] EastlimitAngle = 67.2740[/I] Angle = sin (Pd(2) / (DishpivotOffset - Pd(1) ) ) ; MaxAngledegree = (Angle / (pi/180) ); WestlimitAngle = ( 90 + MaxAngledegree ) - EastlimitAngle [I]WestlimitAngle = 80.0125[/I] Please post reactions or comment . If someone wanted the Matlab file send me a personal message. It also possible to copy / paste this script (only remove the [I]results[/I]) [/QUOTE]

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