calibration
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calibration [2019/07/19 16:04] – visentin | calibration [2019/08/14 14:52] – visentin | ||
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- | ====== Calibration ====== | + | ===== Calibrating the Delta Robot ===== |
- | The '' | + | If you need to calibrate |
- | ==== Mechanical Limits of the Axis Motors ==== | + | - The Delta robot has to be powered |
- | The axis motors have mechanical upper and lower limits. | + | - If the Delta is not in it's homing position: |
+ | | ||
+ | - Else: | ||
+ | - Press the green and blue button together | ||
+ | - Remove all plates | ||
- | ^Upper limit^Upper limit detail^Lower limit^ | + | You have to calibrate the Delta with each plate. Start with plate 0 -> that means no plate is used, and position 0. |
- | |{{: | + | |
- | |Upper limit calculation shown below.| Upper limit calculation detail |Lower limit of the Axis Motor measured on the Delta robot, γ is about 5°.| | + | |
+ | | ||
+ | | ||
+ | - If the actual position is number 3 go to the next step. Else increment | ||
+ | - If the actual plate is number 3 you are finished. Else use the plate with the next higher number and start again with step 1. | ||
- | L = 17.5 \\ | + | If you have calibrated all blocks on every position, put all blocks back and press the blue button. The Delta will move to it's homing position. |
- | B = 15 \\ | + | |
- | s = 4 \\ | + | |
- | + | ||
- | The upper limit can be calculated as follows: | + | |
- | \\ \\ | + | |
- | //(1) tan(β) = sin(β)/ | + | |
- | //(2) cos(β) = s/y// \\ | + | |
- | \\ | + | |
- | Substitute (2) into (1) to get: \\ | + | |
- | \\ | + | |
- | //(3) L*sin(β)-B*cos(β)=-s// \\ | + | |
- | \\ | + | |
- | Using following trigonometric formulas in (3): | + | |
- | \\ \\ | + | |
- | //(4) t = tan(β/2) // \\ | + | |
- | //(5) sin(β) = 2*tan(β/ | + | |
- | //(6) sin(β) = (1-tan^2(β/ | + | |
- | \\ | + | |
- | Leads to: | + | |
- | \\ \\ | + | |
- | // | + | |
- | + | ||
- | + | ||
- | + | ||
- | + | ||
- | OLD OLD OLD | + | |
- | + | ||
- | The subtraction of a cosine function from a sine function results in another sine function with phase shift. So we are looking for a function in the form of \\ | + | |
- | \\ | + | |
- | //(4) A*sin(β+φ) = L*sin(β)-B*cos(β)// | + | |
- | \\ | + | |
- | By using the addition theorem we get \\ | + | |
- | \\ | + | |
- | // | + | |
- | \\ | + | |
- | Now we can compare the coefficients from sin(β) and cos(β) \\ | + | |
- | \\ | + | |
- | //(5) L=A*cos(φ)// | + | |
- | //(6) -B=A*sin(φ)// | + | |
- | \\ | + | |
- | By dividing (6) by (5) we get \\ | + | |
- | \\ | + | |
- | // -B/ | + | |
- | \\ | + | |
- | Taking the square of each function and adding them together results in\\ | + | |
- | \\ | + | |
- | // L< | + | |
- | // A = sqrt(L< | + | |
- | \\ | + | |
- | Inserting the values in (4)\\ | + | |
- | \\ | + | |
- | // | + | |
- | \\ | + | |
- | we can now solve for β\\ | + | |
- | \\ | + | |
- | // | + | |
- | \\ | + | |
- | Hence, the maximum angle the axis can turn is // 90° + γ + β ≅ 120°// | + | |
- | + | ||
- | ==== Mechanical Limits of the Tool Center Point Motor ==== | + | |
- | The TCP rotation is also limited by two metall pins. The maximum turn angle is calculated as follows: | + | |
- | {{ : | + | |
- | + | ||
- | //sin(γ/2) = r/R//\\ | + | |
- | // | + | |
- | \\ | + | |
- | That is the value for one side. The other side is identical, so the maximum turn angle is\\ | + | |
- | \\ | + | |
- | //2*PI - 2 * 0.06 = 6.16 (rad) ≅ 353°//. | + | |