Merge pull request #2838 from wavexx/m204_travel_acceleration

Implement M204 T (separate travel acceleration)

Firmware/ConfigurationStore.cpp

@@ -96,7 +96,7 @@ void Config_PrintSettings(uint8_t level)
 		"%SMaximum feedrates - stealth (mm/s):\n%S  M203 X%.2f Y%.2f Z%.2f E%.2f\n"
 		"%SMaximum acceleration - normal (mm/s2):\n%S  M201 X%lu Y%lu Z%lu E%lu\n"
 		"%SMaximum acceleration - stealth (mm/s2):\n%S  M201 X%lu Y%lu Z%lu E%lu\n"
-		"%SAcceleration: S=acceleration, T=retract acceleration\n%S  M204 S%.2f T%.2f\n"
+		"%SAcceleration: P=print, R=retract, T=travel\n%S  M204 P%.2f R%.2f T%.2f\n"
 		"%SAdvanced variables: S=Min feedrate (mm/s), T=Min travel feedrate (mm/s), B=minimum segment time (ms), X=maximum XY jerk (mm/s),  Z=maximum Z jerk (mm/s),  E=maximum E jerk (mm/s)\n%S  M205 S%.2f T%.2f B%.2f X%.2f Y%.2f Z%.2f E%.2f\n"
 		"%SHome offset (mm):\n%S  M206 X%.2f Y%.2f Z%.2f\n"
 		),
@@ -106,7 +106,7 @@ void Config_PrintSettings(uint8_t level)
 		echomagic, echomagic, cs.max_feedrate_silent[X_AXIS], cs.max_feedrate_silent[Y_AXIS], cs.max_feedrate_silent[Z_AXIS], cs.max_feedrate_silent[E_AXIS],
 		echomagic, echomagic, cs.max_acceleration_units_per_sq_second_normal[X_AXIS], cs.max_acceleration_units_per_sq_second_normal[Y_AXIS], cs.max_acceleration_units_per_sq_second_normal[Z_AXIS], cs.max_acceleration_units_per_sq_second_normal[E_AXIS],
 		echomagic, echomagic, cs.max_acceleration_units_per_sq_second_silent[X_AXIS], cs.max_acceleration_units_per_sq_second_silent[Y_AXIS], cs.max_acceleration_units_per_sq_second_silent[Z_AXIS], cs.max_acceleration_units_per_sq_second_silent[E_AXIS],
-		echomagic, echomagic, cs.acceleration, cs.retract_acceleration,
+		echomagic, echomagic, cs.acceleration, cs.retract_acceleration, cs.travel_acceleration,
 		echomagic, echomagic, cs.minimumfeedrate, cs.mintravelfeedrate, cs.minsegmenttime, cs.max_jerk[X_AXIS], cs.max_jerk[Y_AXIS], cs.max_jerk[Z_AXIS], cs.max_jerk[E_AXIS],
 		echomagic, echomagic, cs.add_homing[X_AXIS], cs.add_homing[Y_AXIS], cs.add_homing[Z_AXIS]
 #else //TMC2130
@@ -114,14 +114,14 @@ void Config_PrintSettings(uint8_t level)
 		"%SSteps per unit:\n%S  M92 X%.2f Y%.2f Z%.2f E%.2f\n"
 		"%SMaximum feedrates (mm/s):\n%S  M203 X%.2f Y%.2f Z%.2f E%.2f\n"
 		"%SMaximum acceleration (mm/s2):\n%S  M201 X%lu Y%lu Z%lu E%lu\n"
-		"%SAcceleration: S=acceleration, T=retract acceleration\n%S  M204 S%.2f T%.2f\n"
+		"%SAcceleration: P=print, R=retract, T=travel\n%S  M204 P%.2f R%.2f T%.2f\n"
 		"%SAdvanced variables: S=Min feedrate (mm/s), T=Min travel feedrate (mm/s), B=minimum segment time (ms), X=maximum XY jerk (mm/s),  Z=maximum Z jerk (mm/s),  E=maximum E jerk (mm/s)\n%S  M205 S%.2f T%.2f B%.2f X%.2f Y%.2f Z%.2f E%.2f\n"
 		"%SHome offset (mm):\n%S  M206 X%.2f Y%.2f Z%.2f\n"
 		),
 		echomagic, echomagic, cs.axis_steps_per_unit[X_AXIS], cs.axis_steps_per_unit[Y_AXIS], cs.axis_steps_per_unit[Z_AXIS], cs.axis_steps_per_unit[E_AXIS],
 		echomagic, echomagic, max_feedrate[X_AXIS], max_feedrate[Y_AXIS], max_feedrate[Z_AXIS], max_feedrate[E_AXIS],
 		echomagic, echomagic, max_acceleration_units_per_sq_second[X_AXIS], max_acceleration_units_per_sq_second[Y_AXIS], max_acceleration_units_per_sq_second[Z_AXIS], max_acceleration_units_per_sq_second[E_AXIS],
-		echomagic, echomagic, cs.acceleration, cs.retract_acceleration,
+		echomagic, echomagic, cs.acceleration, cs.retract_acceleration, cs.travel_acceleration,
 		echomagic, echomagic, cs.minimumfeedrate, cs.mintravelfeedrate, cs.minsegmenttime, cs.max_jerk[X_AXIS], cs.max_jerk[Y_AXIS], cs.max_jerk[Z_AXIS], cs.max_jerk[E_AXIS],
 		echomagic, echomagic, cs.add_homing[X_AXIS], cs.add_homing[Y_AXIS], cs.add_homing[Z_AXIS]
 #endif //TMC2130
@@ -184,7 +184,7 @@ static_assert (false, "zprobe_zoffset was not initialized in printers in field t
         "0.0, if this is not acceptable, increment EEPROM_VERSION to force use default_conf");
 #endif
 
-static_assert (sizeof(M500_conf) == 192, "sizeof(M500_conf) has changed, ensure that EEPROM_VERSION has been incremented, "
+static_assert (sizeof(M500_conf) == 196, "sizeof(M500_conf) has changed, ensure that EEPROM_VERSION has been incremented, "
         "or if you added members in the end of struct, ensure that historically uninitialized values will be initialized."
         "If this is caused by change to more then 8bit processor, decide whether make this struct packed to save EEPROM,"
         "leave as it is to keep fast code, or reorder struct members to pack more tightly.");
@@ -232,8 +232,21 @@ static const M500_conf default_conf PROGMEM =
 #else // TMC2130
     {16,16,16,16},
 #endif
+    DEFAULT_TRAVEL_ACCELERATION,
 };
 
+
+static bool is_uninitialized(void* addr, uint8_t len)
+{
+    while(len--)
+    {
+        if(reinterpret_cast<uint8_t*>(addr)[len] != 0xff)
+            return false;
+    }
+    return true;
+}
+
+
 //! @brief Read M500 configuration
 //! @retval true Succeeded. Stored settings retrieved or default settings retrieved in case EEPROM has been erased.
 //! @retval false Failed. Default settings has been retrieved, because of older version or corrupted data.
@@ -257,13 +270,9 @@ bool Config_RetrieveSettings()
         for (uint8_t i = 0; i < (sizeof(cs.max_feedrate_silent)/sizeof(cs.max_feedrate_silent[0])); ++i)
         {
             const uint32_t erased = 0xffffffff;
-            bool initialized = false;
-
-            for(uint8_t j = 0; j < sizeof(float); ++j)
-            {
-                if(0xff != reinterpret_cast<uint8_t*>(&(cs.max_feedrate_silent[i]))[j]) initialized = true;
+            if (is_uninitialized(&(cs.max_feedrate_silent[i]), sizeof(float))) {
+                memcpy_P(&cs.max_feedrate_silent[i],&default_conf.max_feedrate_silent[i], sizeof(cs.max_feedrate_silent[i]));
             }
-            if (!initialized) memcpy_P(&cs.max_feedrate_silent[i],&default_conf.max_feedrate_silent[i], sizeof(cs.max_feedrate_silent[i]));
             if (erased == cs.max_acceleration_units_per_sq_second_silent[i]) {
                 memcpy_P(&cs.max_acceleration_units_per_sq_second_silent[i],&default_conf.max_acceleration_units_per_sq_second_silent[i],sizeof(cs.max_acceleration_units_per_sq_second_silent[i]));
             }
@@ -293,6 +302,9 @@ bool Config_RetrieveSettings()
 		tmc2130_set_res(E_AXIS, cs.axis_ustep_resolution[E_AXIS]);
 #endif //TMC2130
 
+        if(is_uninitialized(&cs.travel_acceleration, sizeof(cs.travel_acceleration)))
+            cs.travel_acceleration = cs.acceleration;
+
 		reset_acceleration_rates();
 
 		// Call updatePID (similar to when we have processed M301)

Firmware/ConfigurationStore.h

@@ -38,6 +38,7 @@ typedef struct
     float max_feedrate_silent[4]; //!< max speeds for silent mode
     unsigned long max_acceleration_units_per_sq_second_silent[4];
     unsigned char axis_ustep_resolution[4];
+    float travel_acceleration; //!< travel acceleration mm/s^2
 } M500_conf;
 
 extern M500_conf cs;

Firmware/Marlin_main.cpp

@@ -7260,7 +7260,7 @@ Sigma_Exit:
           // Legacy acceleration format. This format is used by the legacy Marlin, MK2 or MK3 firmware,
           // and it is also generated by Slic3r to control acceleration per extrusion type
           // (there is a separate acceleration settings in Slicer for perimeter, first layer etc).
-          cs.acceleration = code_value();
+          cs.acceleration = cs.travel_acceleration = code_value();
           // Interpret the T value as retract acceleration in the old Marlin format.
           if(code_seen('T'))
             cs.retract_acceleration = code_value();
@@ -7270,13 +7270,8 @@ Sigma_Exit:
             cs.acceleration = code_value();
           if(code_seen('R'))
             cs.retract_acceleration = code_value();
-          if(code_seen('T')) {
-            // Interpret the T value as the travel acceleration in the new Marlin format.
-            /*!
-            @todo Prusa3D firmware currently does not support travel acceleration value independent from the extruding acceleration value.
-            */
-            // travel_acceleration = code_value();
-          }
+          if(code_seen('T'))
+            cs.travel_acceleration = code_value();
         }
       }
       break;
@@ -10970,6 +10965,10 @@ void uvlo_()
 #endif
 	eeprom_update_word((uint16_t*)(EEPROM_EXTRUDEMULTIPLY), (uint16_t)extrudemultiply);
 
+	eeprom_update_float((float*)(EEPROM_UVLO_ACCELL), cs.acceleration);
+	eeprom_update_float((float*)(EEPROM_UVLO_RETRACT_ACCELL), cs.retract_acceleration);
+	eeprom_update_float((float*)(EEPROM_UVLO_TRAVEL_ACCELL), cs.travel_acceleration);
+
     // Store the saved target
     eeprom_update_float((float*)(EEPROM_UVLO_SAVED_TARGET+0*4), saved_target[X_AXIS]);
     eeprom_update_float((float*)(EEPROM_UVLO_SAVED_TARGET+1*4), saved_target[Y_AXIS]);
@@ -11314,6 +11313,13 @@ void restore_print_from_eeprom(bool mbl_was_active) {
     sprintf_P(cmd, PSTR("G1 Z%f"), eeprom_read_float((float*)(EEPROM_UVLO_CURRENT_POSITION_Z)));
 	enquecommand(cmd);
 
+    // Restore acceleration settings
+    float acceleration = eeprom_read_float((float*)(EEPROM_UVLO_ACCELL));
+    float retract_acceleration = eeprom_read_float((float*)(EEPROM_UVLO_RETRACT_ACCELL));
+    float travel_acceleration = eeprom_read_float((float*)(EEPROM_UVLO_TRAVEL_ACCELL));
+    sprintf_P(cmd, PSTR("M204 P%f R%f T%f"), acceleration, retract_acceleration, travel_acceleration);
+    enquecommand(cmd);
+
   // Unretract.
     sprintf_P(cmd, PSTR("G1 E%0.3f F2700"), default_retraction);
     enquecommand(cmd);

Firmware/eeprom.h

@@ -319,8 +319,10 @@ static_assert(sizeof(Sheets) == EEPROM_SHEETS_SIZEOF, "Sizeof(Sheets) is not EEP
 | ^					| ^			| ^										| 00h 0			| ^						| PINDA has no temp compensation PINDA v1/2    		| ^				| ^
 | ^					| ^			| ^										| 01h 1			| ^						| PINDA has temp compensation aka SuperPINDA       	| ^				| ^
 | 0x0D15 3349		| char[20]	| EEPROM_PRUSA_SN						| SN[19] == 0	| ffffffffffffffff...	| PRUSA Serial number string						| PRUSA SN		| D3 Ax0d15 C20
+| 0x0D11 3345		| float		| EEPROM_UVLO_ACCELL                	| ???			| ff ff ff ffh			| Power panic saved normal acceleration     		| ???			| D3 Ax0d11 C4
+| 0x0D0D 3341		| float		| EEPROM_UVLO_RETRACT_ACCELL			| ???			| ff ff ff ffh			| Power panic saved retract acceleration     		| ???			| D3 Ax0d0d C4
+| 0x0D09 3337		| float		| EEPROM_UVLO_TRAVEL_ACCELL				| ???			| ff ff ff ffh			| Power panic saved travel acceleration     		| ???			| D3 Ax0d09 C4
 
-  
 | Address begin		| Bit/Type 	| Name 									| Valid values	| Default/FactoryReset	| Description 										| Gcode/Function| Debug code
 | :--:				| :--: 		| :--: 									| :--:			| :--:					| :--:												| :--:			| :--:
 | 0x0012 18			| uint16	| EEPROM_FIRMWARE_VERSION_END			| ???			| ff ffh 65535			| ???												| ???			| D3 Ax0012 C2
@@ -525,8 +527,13 @@ static Sheets * const EEPROM_Sheets_base = (Sheets*)(EEPROM_SHEETS_BASE);
 #define EEPROM_EXPERIMENTAL_VISIBILITY (EEPROM_ALTFAN_OVERRIDE-1) //uint8
 #define EEPROM_PINDA_TEMP_COMPENSATION (EEPROM_EXPERIMENTAL_VISIBILITY-1) //uint8
 #define EEPROM_PRUSA_SN (EEPROM_PINDA_TEMP_COMPENSATION-20) //char[20]
+
+#define EEPROM_UVLO_ACCELL (EEPROM_PRUSA_SN-4) // float
+#define EEPROM_UVLO_RETRACT_ACCELL (EEPROM_UVLO_ACCELL-4) // float
+#define EEPROM_UVLO_TRAVEL_ACCELL (EEPROM_UVLO_RETRACT_ACCELL-4) // float
+
 //This is supposed to point to last item to allow EEPROM overrun check. Please update when adding new items.
-#define EEPROM_LAST_ITEM EEPROM_PRUSA_SN
+#define EEPROM_LAST_ITEM EEPROM_UVLO_TRAVEL_ACCELL
 // !!!!!
 // !!!!! this is end of EEPROM section ... all updates MUST BE inserted before this mark !!!!!
 // !!!!!

Firmware/planner.cpp

@@ -1082,7 +1082,8 @@ Having the real displacement of the head, we can calculate the total movement le
   }
   else
   {
-    block->acceleration_st = ceil(cs.acceleration * steps_per_mm); // convert to: acceleration steps/sec^2
+    float acceleration = (block->steps_e.wide == 0? cs.travel_acceleration: cs.acceleration);
+    block->acceleration_st = ceil(acceleration * steps_per_mm); // convert to: acceleration steps/sec^2
 
     #ifdef LIN_ADVANCE
     /**

Firmware/variants/1_75mm_MK2-RAMBo10a-E3Dv6full.h

@@ -90,8 +90,9 @@ AXIS SETTINGS
 #define DEFAULT_MAX_ACCELERATION      {9000,9000,500,10000}    // X, Y, Z, E maximum start speed for accelerated moves. E default values are good for Skeinforge 40+, for older versions raise them a lot.
 #define DEFAULT_MAX_ACCELERATION_SILENT     {960, 960, 200, 5000}    // (mm/sec^2) max acceleration (M201), silent mode
 
-#define DEFAULT_ACCELERATION          1500    // X, Y, Z and E max acceleration in mm/s^2 for printing moves
+#define DEFAULT_ACCELERATION          1500   // X, Y, Z and E max acceleration in mm/s^2 for printing moves
 #define DEFAULT_RETRACT_ACCELERATION  1500   // X, Y, Z and E max acceleration in mm/s^2 for retracts
+#define DEFAULT_TRAVEL_ACCELERATION   1500   // X, Y, Z and E max acceleration in mm/s^2 for travels
 
 
 #define MANUAL_FEEDRATE {3000, 3000, 1000, 100}   // set the speeds for manual moves (mm/min)

Firmware/variants/1_75mm_MK2-RAMBo13a-E3Dv6full.h

@@ -90,8 +90,9 @@ AXIS SETTINGS
 #define DEFAULT_MAX_ACCELERATION      {9000,9000,500,10000}    // X, Y, Z, E maximum start speed for accelerated moves. E default values are good for Skeinforge 40+, for older versions raise them a lot.
 #define DEFAULT_MAX_ACCELERATION_SILENT     {960, 960, 200, 5000}    // (mm/sec^2) max acceleration (M201), silent mode
 
-#define DEFAULT_ACCELERATION          1500    // X, Y, Z and E max acceleration in mm/s^2 for printing moves
+#define DEFAULT_ACCELERATION          1500   // X, Y, Z and E max acceleration in mm/s^2 for printing moves
 #define DEFAULT_RETRACT_ACCELERATION  1500   // X, Y, Z and E max acceleration in mm/s^2 for retracts
+#define DEFAULT_TRAVEL_ACCELERATION   1500   // X, Y, Z and E max acceleration in mm/s^2 for travels
 
 
 #define MANUAL_FEEDRATE {3000, 3000, 1000, 100}   // set the speeds for manual moves (mm/min)

Firmware/variants/1_75mm_MK25-RAMBo10a-E3Dv6full.h

@@ -94,8 +94,9 @@
 #define DEFAULT_MAX_ACCELERATION      {1000, 1000, 200, 5000}  // (mm/sec^2) max acceleration (M201)
 #define DEFAULT_MAX_ACCELERATION_SILENT     {960, 960, 200, 5000}    // (mm/sec^2) max acceleration (M201), silent mode
 
-#define DEFAULT_ACCELERATION          1250   // X, Y, Z and E max acceleration in mm/s^2 for printing moves (M204S)
-#define DEFAULT_RETRACT_ACCELERATION  1250   // X, Y, Z and E max acceleration in mm/s^2 for retracts (M204T)
+#define DEFAULT_ACCELERATION          1250   // X, Y, Z and E max acceleration in mm/s^2 for printing moves (M204P)
+#define DEFAULT_RETRACT_ACCELERATION  1250   // X, Y, Z and E max acceleration in mm/s^2 for retracts (M204R)
+#define DEFAULT_TRAVEL_ACCELERATION   1250   // X, Y, Z and E max acceleration in mm/s^2 for travels (M204T)
 
 #define MANUAL_FEEDRATE {2700, 2700, 1000, 100}   // set the speeds for manual moves (mm/min)
 

Firmware/variants/1_75mm_MK25-RAMBo13a-E3Dv6full.h

@@ -95,8 +95,9 @@
 #define DEFAULT_MAX_ACCELERATION_SILENT     {960, 960, 200, 5000}    // (mm/sec^2) max acceleration (M201), silent mode
 
 
-#define DEFAULT_ACCELERATION          1250   // X, Y, Z and E max acceleration in mm/s^2 for printing moves (M204S)
-#define DEFAULT_RETRACT_ACCELERATION  1250   // X, Y, Z and E max acceleration in mm/s^2 for retracts (M204T)
+#define DEFAULT_ACCELERATION          1250   // X, Y, Z and E max acceleration in mm/s^2 for printing moves (M204P)
+#define DEFAULT_RETRACT_ACCELERATION  1250   // X, Y, Z and E max acceleration in mm/s^2 for retracts (M204R)
+#define DEFAULT_TRAVEL_ACCELERATION   1250   // X, Y, Z and E max acceleration in mm/s^2 for travels (M204T)
 
 #define MANUAL_FEEDRATE {2700, 2700, 1000, 100}   // set the speeds for manual moves (mm/min)
 

Firmware/variants/1_75mm_MK25S-RAMBo10a-E3Dv6full.h

@@ -94,8 +94,9 @@
 #define DEFAULT_MAX_ACCELERATION      {1000, 1000, 200, 5000}  // (mm/sec^2) max acceleration (M201)
 #define DEFAULT_MAX_ACCELERATION_SILENT     {960, 960, 200, 5000}    // (mm/sec^2) max acceleration (M201), silent mode
 
-#define DEFAULT_ACCELERATION          1250   // X, Y, Z and E max acceleration in mm/s^2 for printing moves (M204S)
-#define DEFAULT_RETRACT_ACCELERATION  1250   // X, Y, Z and E max acceleration in mm/s^2 for retracts (M204T)
+#define DEFAULT_ACCELERATION          1250   // X, Y, Z and E max acceleration in mm/s^2 for printing moves (M204P)
+#define DEFAULT_RETRACT_ACCELERATION  1250   // X, Y, Z and E max acceleration in mm/s^2 for retracts (M204R)
+#define DEFAULT_TRAVEL_ACCELERATION   1250   // X, Y, Z and E max acceleration in mm/s^2 for travels (M204T)
 
 #define MANUAL_FEEDRATE {2700, 2700, 1000, 100}   // set the speeds for manual moves (mm/min)
 

Firmware/variants/1_75mm_MK25S-RAMBo13a-E3Dv6full.h

@@ -95,8 +95,9 @@
 #define DEFAULT_MAX_ACCELERATION_SILENT     {960, 960, 200, 5000}    // (mm/sec^2) max acceleration (M201), silent mode
 
 
-#define DEFAULT_ACCELERATION          1250   // X, Y, Z and E max acceleration in mm/s^2 for printing moves (M204S)
-#define DEFAULT_RETRACT_ACCELERATION  1250   // X, Y, Z and E max acceleration in mm/s^2 for retracts (M204T)
+#define DEFAULT_ACCELERATION          1250   // X, Y, Z and E max acceleration in mm/s^2 for printing moves (M204P)
+#define DEFAULT_RETRACT_ACCELERATION  1250   // X, Y, Z and E max acceleration in mm/s^2 for retracts (M204R)
+#define DEFAULT_TRAVEL_ACCELERATION   1250   // X, Y, Z and E max acceleration in mm/s^2 for travels (M204T)
 
 #define MANUAL_FEEDRATE {2700, 2700, 1000, 100}   // set the speeds for manual moves (mm/min)
 

Firmware/variants/1_75mm_MK3-EINSy10a-E3Dv6full.h

@@ -99,8 +99,9 @@
 #define DEFAULT_MAX_ACCELERATION_SILENT     {960, 960, 200, 5000}    // (mm/sec^2) max acceleration (M201), silent mode
 
 
-#define DEFAULT_ACCELERATION          1250   // X, Y, Z and E max acceleration in mm/s^2 for printing moves (M204S)
-#define DEFAULT_RETRACT_ACCELERATION  1250   // X, Y, Z and E max acceleration in mm/s^2 for retracts (M204T)
+#define DEFAULT_ACCELERATION          1250   // X, Y, Z and E max acceleration in mm/s^2 for printing moves (M204P)
+#define DEFAULT_RETRACT_ACCELERATION  1250   // X, Y, Z and E max acceleration in mm/s^2 for retracts (M204R)
+#define DEFAULT_TRAVEL_ACCELERATION   1250   // X, Y, Z and E max acceleration in mm/s^2 for travels (M204T)
 
 #define MANUAL_FEEDRATE {2700, 2700, 1000, 100}   // set the speeds for manual moves (mm/min)
 

Firmware/variants/1_75mm_MK3S-EINSy10a-E3Dv6full.h

@@ -101,8 +101,9 @@
 #define DEFAULT_MAX_ACCELERATION_SILENT     {960, 960, 200, 5000}    // (mm/sec^2) max acceleration (M201), silent mode
 
 
-#define DEFAULT_ACCELERATION          1250   // X, Y, Z and E max acceleration in mm/s^2 for printing moves (M204S)
-#define DEFAULT_RETRACT_ACCELERATION  1250   // X, Y, Z and E max acceleration in mm/s^2 for retracts (M204T)
+#define DEFAULT_ACCELERATION          1250   // X, Y, Z and E max acceleration in mm/s^2 for printing moves (M204P)
+#define DEFAULT_RETRACT_ACCELERATION  1250   // X, Y, Z and E max acceleration in mm/s^2 for retracts (M204R)
+#define DEFAULT_TRAVEL_ACCELERATION   1250   // X, Y, Z and E max acceleration in mm/s^2 for travels (M204T)
 
 #define MANUAL_FEEDRATE {2700, 2700, 1000, 100}   // set the speeds for manual moves (mm/min)