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/*
* DriveMovement.cpp
*
* Created on: 17 Jan 2015
* Author: David
*/
#include "DriveMovement.h"
#include "DDA.h"
#include "Move.h"
#include "RepRap.h"
#include "Libraries/Math/Isqrt.h"
// Prepare this DM for a Cartesian axis move
void DriveMovement::PrepareCartesianAxis(const DDA& dda, const PrepParams& params)
{
const float stepsPerMm = reprap.GetPlatform()->DriveStepsPerUnit(drive) * fabsf(reprap.GetMove()->MotorFactor(drive, dda.directionVector));
mp.cart.twoCsquaredTimesMmPerStepDivA = (uint64_t)(((float)DDA::stepClockRate * (float)DDA::stepClockRate)/(stepsPerMm * dda.acceleration)) * 2;
// Acceleration phase parameters
mp.cart.accelStopStep = (uint32_t)(dda.accelDistance * stepsPerMm) + 1;
startSpeedTimesCdivA = params.startSpeedTimesCdivA;
// Constant speed phase parameters
mp.cart.mmPerStepTimesCdivtopSpeed = (uint32_t)(((float)DDA::stepClockRate * K1)/(stepsPerMm * dda.topSpeed));
accelClocksMinusAccelDistanceTimesCdivTopSpeed = params.accelClocksMinusAccelDistanceTimesCdivTopSpeed;
// Deceleration phase parameters
// First check whether there is any deceleration at all, otherwise we may get strange results because of rounding errors
if (dda.decelDistance * stepsPerMm < 0.5)
{
mp.cart.decelStartStep = totalSteps + 1;
topSpeedTimesCdivAPlusDecelStartClocks = 0;
twoDistanceToStopTimesCsquaredDivA = 0;
}
else
{
mp.cart.decelStartStep = (uint32_t)(params.decelStartDistance * stepsPerMm) + 1;
topSpeedTimesCdivAPlusDecelStartClocks = params.topSpeedTimesCdivAPlusDecelStartClocks;
const uint64_t initialDecelSpeedTimesCdivASquared = isquare64(params.topSpeedTimesCdivA);
twoDistanceToStopTimesCsquaredDivA = initialDecelSpeedTimesCdivASquared + (uint64_t)((params.decelStartDistance * (DDA::stepClockRateSquared * 2))/dda.acceleration);
}
// No reverse phase
reverseStartStep = totalSteps + 1;
mp.cart.fourMaxStepDistanceMinusTwoDistanceToStopTimesCsquaredDivA = 0;
}
// Prepare this DM for a Delta axis move
void DriveMovement::PrepareDeltaAxis(const DDA& dda, const PrepParams& params)
{
const float stepsPerMm = reprap.GetPlatform()->DriveStepsPerUnit(drive);
mp.delta.twoCsquaredTimesMmPerStepDivAK = (uint32_t)((float)DDA::stepClockRateSquared/(stepsPerMm * dda.acceleration * (K2/2)));
// Acceleration phase parameters
mp.delta.accelStopDsK = (uint32_t)(dda.accelDistance * stepsPerMm * K2);
startSpeedTimesCdivA = params.startSpeedTimesCdivA;
// Constant speed phase parameters
mp.delta.mmPerStepTimesCdivtopSpeedK = (uint32_t)(((float)DDA::stepClockRate * K1)/(stepsPerMm * dda.topSpeed));
accelClocksMinusAccelDistanceTimesCdivTopSpeed = params.accelClocksMinusAccelDistanceTimesCdivTopSpeed;
// Deceleration phase parameters
// First check whether there is any deceleration at all, otherwise we may get strange results because of rounding errors
if (dda.decelDistance * stepsPerMm < 0.5)
{
mp.delta.decelStartDsK = 0xFFFFFFFF;
topSpeedTimesCdivAPlusDecelStartClocks = 0;
twoDistanceToStopTimesCsquaredDivA = 0;
}
else
{
mp.delta.decelStartDsK = (uint32_t)(params.decelStartDistance * stepsPerMm * K2);
topSpeedTimesCdivAPlusDecelStartClocks = params.topSpeedTimesCdivAPlusDecelStartClocks;
const uint64_t initialDecelSpeedTimesCdivASquared = isquare64(params.topSpeedTimesCdivA);
twoDistanceToStopTimesCsquaredDivA = initialDecelSpeedTimesCdivASquared + (uint64_t)((params.decelStartDistance * (DDA::stepClockRateSquared * 2))/dda.acceleration);
}
}
// Prepare this DM for an extruder move
void DriveMovement::PrepareExtruder(const DDA& dda, const PrepParams& params, bool doCompensation)
{
const float dv = dda.directionVector[drive];
const float stepsPerMm = reprap.GetPlatform()->DriveStepsPerUnit(drive) * fabsf(dv);
mp.cart.twoCsquaredTimesMmPerStepDivA = (uint64_t)(((float)DDA::stepClockRate * (float)DDA::stepClockRate)/(stepsPerMm * dda.acceleration)) * 2;
// Calculate the pressure advance parameter
const float compensationTime = (doCompensation && dv > 0.0) ? reprap.GetPlatform()->GetPressureAdvance(drive - reprap.GetGCodes()->GetNumAxes()) : 0.0;
const uint32_t compensationClocks = (uint32_t)(compensationTime * DDA::stepClockRate);
// Calculate the net total step count to allow for compensation. It may be negative.
// Note that we add totalSteps in floating point mode, to round the number of steps down consistently
const float compensationDistance = (dda.endSpeed - dda.startSpeed) * compensationTime;
const int32_t netSteps = (int32_t)(compensationDistance * stepsPerMm) + (int32_t)totalSteps;
// Calculate the acceleration phase parameters
const float accelCompensationDistance = compensationTime * (dda.topSpeed - dda.startSpeed);
// Acceleration phase parameters
mp.cart.accelStopStep = (uint32_t)((dda.accelDistance + accelCompensationDistance) * stepsPerMm) + 1;
startSpeedTimesCdivA = params.startSpeedTimesCdivA + compensationClocks;
// Constant speed phase parameters
mp.cart.mmPerStepTimesCdivtopSpeed = (uint32_t)(((float)DDA::stepClockRate * K1)/(stepsPerMm * dda.topSpeed));
accelClocksMinusAccelDistanceTimesCdivTopSpeed = (int32_t)params.accelClocksMinusAccelDistanceTimesCdivTopSpeed - (int32_t)(compensationClocks * params.compFactor);
// Calculate the deceleration and reverse phase parameters
// First check whether there is any deceleration at all, otherwise we may get strange results because of rounding errors
if (dda.decelDistance * stepsPerMm < 0.5) // if less than 1 deceleration step
{
totalSteps = (uint)max<int32_t>(netSteps, 0);
mp.cart.decelStartStep = reverseStartStep = netSteps + 1;
topSpeedTimesCdivAPlusDecelStartClocks = 0;
mp.cart.fourMaxStepDistanceMinusTwoDistanceToStopTimesCsquaredDivA = 0;
twoDistanceToStopTimesCsquaredDivA = 0;
}
else
{
mp.cart.decelStartStep = (uint32_t)((params.decelStartDistance + accelCompensationDistance) * stepsPerMm) + 1;
const int32_t initialDecelSpeedTimesCdivA = (int32_t)params.topSpeedTimesCdivA - (int32_t)compensationClocks; // signed because it may be negative and we square it
const uint64_t initialDecelSpeedTimesCdivASquared = isquare64(initialDecelSpeedTimesCdivA);
topSpeedTimesCdivAPlusDecelStartClocks = params.topSpeedTimesCdivAPlusDecelStartClocks - compensationClocks;
twoDistanceToStopTimesCsquaredDivA =
initialDecelSpeedTimesCdivASquared + (uint64_t)(((params.decelStartDistance + accelCompensationDistance) * (DDA::stepClockRateSquared * 2))/dda.acceleration);
const float initialDecelSpeed = dda.topSpeed - dda.acceleration * compensationTime;
const float reverseStartDistance = (initialDecelSpeed > 0.0)
? fsquare(initialDecelSpeed)/(2 * dda.acceleration) + params.decelStartDistance
: params.decelStartDistance;
// Reverse phase parameters
if (reverseStartDistance >= dda.totalDistance + compensationDistance)
{
// No reverse phase
totalSteps = (uint)max<int32_t>(netSteps, 0);
reverseStartStep = netSteps + 1;
mp.cart.fourMaxStepDistanceMinusTwoDistanceToStopTimesCsquaredDivA = 0;
}
else
{
reverseStartStep = (initialDecelSpeed < 0.0)
? mp.cart.decelStartStep
: (twoDistanceToStopTimesCsquaredDivA/mp.cart.twoCsquaredTimesMmPerStepDivA) + 1;
// Because the step numbers are rounded down, we may sometimes get a situation in which netSteps = 1 and reverseStartStep = 1.
// This would lead to totalSteps = -1, which must be avoided.
const int32_t overallSteps = (int32_t)(2 * (reverseStartStep - 1)) - netSteps;
if (overallSteps > 0)
{
totalSteps = overallSteps;
mp.cart.fourMaxStepDistanceMinusTwoDistanceToStopTimesCsquaredDivA =
(int64_t)((2 * (reverseStartStep - 1)) * mp.cart.twoCsquaredTimesMmPerStepDivA) - (int64_t)twoDistanceToStopTimesCsquaredDivA;
}
else
{
totalSteps = (uint)max<int32_t>(netSteps, 0);
reverseStartStep = totalSteps + 1;
mp.cart.fourMaxStepDistanceMinusTwoDistanceToStopTimesCsquaredDivA = 0;
}
}
}
}
void DriveMovement::DebugPrint(char c, bool isDeltaMovement) const
{
if (state != DMState::idle)
{
debugPrintf("DM%c%s dir=%c steps=%u next=%u rev=%u interval=%u sstcda=%u "
"acmadtcdts=%d tstcdapdsc=%u 2dtstc2diva=%" PRIu64 "\n",
c, (state == DMState::stepError) ? " ERR:" : ":", (direction) ? 'F' : 'B', totalSteps, nextStep, reverseStartStep, stepInterval, startSpeedTimesCdivA,
accelClocksMinusAccelDistanceTimesCdivTopSpeed, topSpeedTimesCdivAPlusDecelStartClocks, twoDistanceToStopTimesCsquaredDivA);
if (isDeltaMovement)
{
debugPrintf("hmz0sK=%d minusAaPlusBbTimesKs=%d dSquaredMinusAsquaredMinusBsquared=%" PRId64 "\n"
"2c2mmsdak=%u asdsk=%u dsdsk=%u mmstcdts=%u\n",
mp.delta.hmz0sK, mp.delta.minusAaPlusBbTimesKs, mp.delta.dSquaredMinusAsquaredMinusBsquaredTimesKsquaredSsquared,
mp.delta.twoCsquaredTimesMmPerStepDivAK, mp.delta.accelStopDsK, mp.delta.decelStartDsK, mp.delta.mmPerStepTimesCdivtopSpeedK
);
}
else
{
debugPrintf("accelStopStep=%u decelStartStep=%u 2CsqtMmPerStepDivA=%" PRIu64 "\n"
"mmPerStepTimesCdivtopSpeed=%u fmsdmtstdca2=%" PRId64 "\n",
mp.cart.accelStopStep, mp.cart.decelStartStep, mp.cart.twoCsquaredTimesMmPerStepDivA,
mp.cart.mmPerStepTimesCdivtopSpeed, mp.cart.fourMaxStepDistanceMinusTwoDistanceToStopTimesCsquaredDivA
);
}
}
else
{
debugPrintf("DM%c: not moving\n", c);
}
}
// Calculate and store the time since the start of the move when the next step for the specified DriveMovement is due.
// Return true if there are more steps to do.
// This is also used for extruders on delta machines.
bool DriveMovement::CalcNextStepTimeCartesianFull(const DDA &dda, bool live)
pre(nextStep < totalSteps; stepsTillRecalc == 0)
{
// Work out how many steps to calculate at a time.
uint32_t shiftFactor;
if (stepInterval < DDA::MinCalcIntervalCartesian)
{
uint32_t stepsToLimit = ((nextStep <= reverseStartStep && reverseStartStep <= totalSteps)
? reverseStartStep
: totalSteps
) - nextStep;
if (stepInterval < DDA::MinCalcIntervalCartesian/4 && stepsToLimit > 8)
{
shiftFactor = 3; // octal stepping
}
else if (stepInterval < DDA::MinCalcIntervalCartesian/2 && stepsToLimit > 4)
{
shiftFactor = 2; // quad stepping
}
else if (stepsToLimit > 2)
{
shiftFactor = 1; // double stepping
}
else
{
shiftFactor = 0; // single stepping
}
}
else
{
shiftFactor = 0; // single stepping
}
stepsTillRecalc = (1u << shiftFactor) - 1u; // store number of additional steps to generate
uint32_t nextCalcStep = nextStep + stepsTillRecalc;
uint32_t lastStepTime = nextStepTime; // pick up the time of the last step
if (nextCalcStep < mp.cart.accelStopStep)
{
// acceleration phase
nextStepTime = isqrt64(isquare64(startSpeedTimesCdivA) + (mp.cart.twoCsquaredTimesMmPerStepDivA * nextCalcStep)) - startSpeedTimesCdivA;
}
else if (nextCalcStep < mp.cart.decelStartStep)
{
// steady speed phase
nextStepTime = (uint32_t)((int32_t)(((uint64_t)mp.cart.mmPerStepTimesCdivtopSpeed * nextCalcStep)/K1) + accelClocksMinusAccelDistanceTimesCdivTopSpeed);
}
else if (nextCalcStep < reverseStartStep)
{
// deceleration phase, not reversed yet
uint64_t temp = mp.cart.twoCsquaredTimesMmPerStepDivA * nextCalcStep;
// Allow for possible rounding error when the end speed is zero or very small
nextStepTime = (twoDistanceToStopTimesCsquaredDivA > temp)
? topSpeedTimesCdivAPlusDecelStartClocks - isqrt64(twoDistanceToStopTimesCsquaredDivA - temp)
: topSpeedTimesCdivAPlusDecelStartClocks;
}
else
{
// deceleration phase, reversing or already reversed
if (nextCalcStep == reverseStartStep)
{
direction = !direction;
if (live)
{
reprap.GetPlatform()->SetDirection(drive, direction);
}
}
nextStepTime = topSpeedTimesCdivAPlusDecelStartClocks
+ isqrt64((int64_t)(mp.cart.twoCsquaredTimesMmPerStepDivA * nextCalcStep) - mp.cart.fourMaxStepDistanceMinusTwoDistanceToStopTimesCsquaredDivA);
}
stepInterval = (nextStepTime - lastStepTime) >> shiftFactor; // calculate the time per step, ready for next time
if (nextStepTime > dda.clocksNeeded)
{
// The calculation makes this step late.
// When the end speed is very low, calculating the time of the last step is very sensitive to rounding error.
// So if this is the last step and it is late, bring it forward to the expected finish time.
// Very rarely on a delta, the penultimate step may also be calculated late. Allow for that here in case it affects Cartesian axes too.
if (nextStep == totalSteps || nextStep + 1 == totalSteps)
{
nextStepTime = dda.clocksNeeded;
}
else
{
// We don't expect any step except the last to be late
state = DMState::stepError;
stepInterval = 10000000 + nextStepTime; // so we can tell what happened in the debug print
return false;
}
}
return true;
}
// Calculate the time since the start of the move when the next step for the specified DriveMovement is due
// Return true if there are more steps to do
bool DriveMovement::CalcNextStepTimeDeltaFull(const DDA &dda, bool live)
pre(nextStep < totalSteps; stepsTillRecalc == 0)
{
// Work out how many steps to calculate at a time.
// The simulator suggests that at 200steps/mm, the minimum step pulse interval for 400mm/sec movement is 4.5us
uint32_t shiftFactor;
if (stepInterval < DDA::MinCalcIntervalDelta)
{
const uint32_t stepsToLimit = ((nextStep < reverseStartStep && reverseStartStep <= totalSteps)
? reverseStartStep
: totalSteps
) - nextStep;
if (stepInterval < DDA::MinCalcIntervalDelta/8 && stepsToLimit > 16)
{
shiftFactor = 4; // hexadecimal stepping
}
else if (stepInterval < DDA::MinCalcIntervalDelta/4 && stepsToLimit > 8)
{
shiftFactor = 3; // octal stepping
}
else if (stepInterval < DDA::MinCalcIntervalDelta/2 && stepsToLimit > 4)
{
shiftFactor = 2; // quad stepping
}
else if (stepsToLimit > 2)
{
shiftFactor = 1; // double stepping
}
else
{
shiftFactor = 0; // single stepping
}
}
else
{
shiftFactor = 0; // single stepping
}
stepsTillRecalc = (1u << shiftFactor) - 1; // store number of additional steps to generate
if (nextStep == reverseStartStep)
{
direction = false;
if (live)
{
reprap.GetPlatform()->SetDirection(drive, false); // going down now
}
}
// Calculate d*s*K as an integer, where d = distance the head has travelled, s = steps/mm for this drive, K = a power of 2 to reduce the rounding errors
if (direction)
{
mp.delta.hmz0sK += (int32_t)(K2 << shiftFactor);
}
else
{
mp.delta.hmz0sK -= (int32_t)(K2 << shiftFactor);
}
const int32_t hmz0scK = (int32_t)(((int64_t)mp.delta.hmz0sK * dda.cKc)/Kc);
const int32_t t1 = mp.delta.minusAaPlusBbTimesKs + hmz0scK;
// Due to rounding error we can end up trying to take the square root of a negative number if we do not take precautions here
const int64_t t2a = (int64_t)isquare64(t1) + mp.delta.dSquaredMinusAsquaredMinusBsquaredTimesKsquaredSsquared - (int64_t)isquare64(mp.delta.hmz0sK);
const int32_t t2 = (t2a > 0) ? isqrt64(t2a) : 0;
const int32_t dsK = (direction) ? t1 - t2 : t1 + t2;
// Now feed dsK into a modified version of the step algorithm for Cartesian motion without elasticity compensation
if (dsK < 0)
{
state = DMState::stepError;
nextStep += 1000000; // so that we can tell what happened in the debug print
return false;
}
uint32_t lastStepTime = nextStepTime; // pick up the time of the last step
if ((uint32_t)dsK < mp.delta.accelStopDsK)
{
// Acceleration phase
nextStepTime = isqrt64(isquare64(startSpeedTimesCdivA) + ((uint64_t)mp.delta.twoCsquaredTimesMmPerStepDivAK * (uint32_t)dsK)) - startSpeedTimesCdivA;
}
else if ((uint32_t)dsK < mp.delta.decelStartDsK)
{
// Steady speed phase
nextStepTime = (uint32_t)((int32_t)(((uint64_t)mp.delta.mmPerStepTimesCdivtopSpeedK * (uint32_t)dsK)/(K1 * K2)) + accelClocksMinusAccelDistanceTimesCdivTopSpeed);
}
else
{
uint64_t temp = (uint64_t)mp.delta.twoCsquaredTimesMmPerStepDivAK * (uint32_t)dsK;
// Because of possible rounding error when the end speed is zero or very small, we need to check that the square root will work OK
nextStepTime = (temp < twoDistanceToStopTimesCsquaredDivA)
? topSpeedTimesCdivAPlusDecelStartClocks - isqrt64(twoDistanceToStopTimesCsquaredDivA - temp)
: topSpeedTimesCdivAPlusDecelStartClocks;
}
stepInterval = (nextStepTime - lastStepTime) >> shiftFactor; // calculate the time per step, ready for next time
if (nextStepTime > dda.clocksNeeded)
{
// The calculation makes this step late.
// When the end speed is very low, calculating the time of the last step is very sensitive to rounding error.
// So if this is the last step and it is late, bring it forward to the expected finish time.
// Very rarely, the penultimate step may be calculated late, so allow for that too.
if (nextStep == totalSteps || nextStep + 1 == totalSteps)
{
nextStepTime = dda.clocksNeeded;
}
else
{
// We don't expect any step except the last to be late
state = DMState::stepError;
stepInterval = 10000000 + nextStepTime; // so we can tell what happened in the debug print
return false;
}
}
return true;
}
// Reduce the speed of this movement. Called to reduce the homing speed when we detect we are near the endstop for a drive.
void DriveMovement::ReduceSpeed(const DDA& dda, float inverseSpeedFactor)
{
if (dda.isDeltaMovement)
{
// Force the linear motion phase
mp.delta.accelStopDsK = 0;
mp.delta.decelStartDsK = 0xFFFFFFFF;
// Adjust the speed
mp.delta.mmPerStepTimesCdivtopSpeedK = (uint32_t)(inverseSpeedFactor * mp.delta.mmPerStepTimesCdivtopSpeedK);
// Adjust the acceleration clocks to as to maintain continuity of movement
const int32_t hmz0scK = (int32_t)(((int64_t)mp.delta.hmz0sK * dda.cKc)/Kc);
const int32_t t1 = mp.delta.minusAaPlusBbTimesKs + hmz0scK;
const int32_t t2 = isqrt64(isquare64(t1) + mp.delta.dSquaredMinusAsquaredMinusBsquaredTimesKsquaredSsquared - isquare64(mp.delta.hmz0sK));
const int32_t dsK = (direction) ? t1 - t2 : t1 + t2;
accelClocksMinusAccelDistanceTimesCdivTopSpeed = (int32_t)nextStepTime - (int32_t)(((uint64_t)mp.delta.mmPerStepTimesCdivtopSpeedK * (uint32_t)dsK)/(K1 * K2));
}
else
{
// Force the linear motion phase
mp.cart.decelStartStep = totalSteps + 1;
mp.cart.accelStopStep = 0;
// Adjust the speed
mp.cart.mmPerStepTimesCdivtopSpeed = (uint32_t)(inverseSpeedFactor * mp.cart.mmPerStepTimesCdivtopSpeed);
// Adjust the acceleration clocks to as to maintain continuity of movement
accelClocksMinusAccelDistanceTimesCdivTopSpeed = (int32_t)nextStepTime - (int32_t)(((uint64_t)mp.cart.mmPerStepTimesCdivtopSpeed * nextStep)/K1);
}
}
// End
|