It appears from previous posts, that the gantry is about 1.5 meters long and rides on rails. What is the support/bearing mechanism for the gantry to ride on the rails? In particular, if there are two or more supports for each side of the gantry, how far apart are the furthest supports on each side?
One of the problems with a gantry style machine is that unless you are careful, the gantry will skew with respect to the other axis. Skewing can cause uneven motion and/or distorted motion. There are a variety of ways to prevent that. For example, if the bearing supports for the gantry are as far apart as the width of the gantry, the forces causing the gantry to skew are resisted. Another technique is to use a motor on each side of the gantry so that the two sides are driven in tandem. A third technique is to use a rack and pinion drive with a rack and pinion on each side and a shaft connecting the two pinions. Then a single motor can drive both sides at once. There are engineering solutions to these engineering problems. A good reference is some of Slocum's books/papers. You can google for them -- I don't have a handy reference. Ken aaron Moore wrote: > One stepper per axis > Gantry runs on X axis rails and weighs about 90kg - 100kg > Y axis weighs about 20 -30 kg > And the spindle and mount 10-20kg > > All axis run directly from trapezoidal screws 16mm dia, 4mm pitch with brass > nuts. > At present it is set for 16 microsteps. > Not sure if this answers the last question > > The motors are actually FL86STH156-4208 > Voltage: 5.25V > Current (phase): 4.2A > Resistance (Phase): 1.25Ohm > Inductance (Phase): 8mH > Holding Torque: 11.96Nm > Length: 156mm > > Thanks > > Aaron > > >> ----- Original Message ----- >> From: "Dave Engvall" <[EMAIL PROTECTED]> >> To: "Enhanced Machine Controller (EMC)" <emc-users@lists.sourceforge.net> >> Subject: [Emc-users] Micro stepper driver MSD542 / KL-5042 cont >> Date: Wed, 21 May 2008 13:26:15 -0700 >> >> >> Aaron, >> >> Other responders have indicated they needed more infomation. >> If you can fill in the blanks and confirm or correct assumptions >> then someone has a real chance of providing >> concrete help. It won't be me as I'm a servo person. Sorry. >> >> OK, lets gather some more information here: >> >> Stated or implied. 1.5m x 1.5 m gantry. One stepper motor per axis. >> I assume the gantry is the X axis and the Y which lags is mounted on the X. >> How much weight are you driving per axis? >> How do you drive the axes; eg. gears, timing belts, etc and what >> are the ratios? >> Another way to put this is one step moves you how far? >> Step rate under normal conditions. >> >> >> >> This info is for the stepper experts. :-) >> Copied off a vendor site. >> >> Stepper motor: >> >> The FL60STH86-3008BF is a High Torque three stack Nema 23, 1.8 >> degree hybrid stepper motor with a holding torque of 3Nm (425 >> Oz-in) >> >> Driver: >> >> Supply voltage up to +50VDC, current output >> up to 4.2A peak >> Optically isolated input signals, pulse >> frequency up to 400 KHz >> Automatic idle-current reduction >> 3-state current control for less motor heating >> 15 selectable resolutions in decimal and >> binary >> Suitable for 4,6,8 lead motors >> Stepping on upward or downward pulse edge >> (selectable) >> DIP switch current settingvalue >> >> >> 4.1 Connector P1 configuration >> Signal Functions >> PUL+(+5V) >> PUL- (PUL) >> Pulse signal: in single pulse(pulse/direction) mode, this input >> represents pulse signal, >> effective for each upward – rising edge; in double pulse mode >> (pulse/ pulse) this input >> represents clockwise(CW)pulse. For reliable response, pulse width >> should be longer >> than 1.5μs. >> DIR+ (+5V) >> >> DIR- (DIR) >> Direction signal: in single-pulse mode, this signal has low/high >> voltage levels, >> representing two directions of motor rotation; in double-pulse mode >> (set by inside >> jumper JMP1), this signal is counter-clock (CCW) pulse, effective >> on each rising edge. >> For reliable motion response, direction signal should be sent to >> driver 2μs before the >> first pulse in the reverse motion direction. >> ENA+ (+5V) >> ENA- (ENA) Enable signal: this signal is used for enable/disable, >> high level for enabling driver and low level for disabling driver. >> Usually left unconnected(enabled). >> >> HTH >> >> Dave >> >> ------------------------------------------------------------------------- >> This SF.net email is sponsored by: Microsoft >> Defy all challenges. Microsoft(R) Visual Studio 2008. >> http://clk.atdmt.com/MRT/go/vse0120000070mrt/direct/01/ >> >> _______________________________________________ >> Emc-users mailing list >> Emc-users@lists.sourceforge.net >> https://lists.sourceforge.net/lists/listinfo/emc-users > > > -- Kenneth Lerman Mark Kenny Products Company, LLC 55 Main Street Newtown, CT 06470 888-ISO-SEVO 203-426-7166 ------------------------------------------------------------------------- This SF.net email is sponsored by: Microsoft Defy all challenges. Microsoft(R) Visual Studio 2008. http://clk.atdmt.com/MRT/go/vse0120000070mrt/direct/01/ _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
