National Instruments NI-Motion - Manual

Contents NI-Motion User Manual x ni.com C/C++ Code .................................................................................................... 14-6 Running, Stopping, and Pausing Onboard Programs .................................................... 14-8 Running an Onboard Program .............

Contents © National Instruments Corporation xi NI-Motion User Manual Blending Straight-Line Move Segments........................................................................ 15-7 Raster Scanning Using Blended Straight Lines Algorithm ............................. 15-8LabVIEW Code ..................

© National Instruments Corporation xiii NI-Motion User Manual About This Manual This manual provides information about the NI-Motion driver software, including background, configuration, and programming information. The purpose of this manual is to provide a basic understanding of the NI-Motion driv...

About This Manual NI-Motion User Manual xiv ni.com italic Italic text denotes variables, emphasis, a cross reference, or an introduction to a key concept. Italic text also denotes text that is a placeholder for a word or value that you must supply. monospace Text in this font denotes text or charact...

© National Instruments Corporation I-1 NI-Motion User Manual Part I Introduction This user manual provides information about the NI-Motion driver software, motion control setup, and specific task-based instructions for creating motion control applications using the LabVIEW and C/C++ application deve...

© National Instruments Corporation 1-1 NI-Motion User Manual 1 Introduction to NI-Motion About NI-Motion NI-Motion is the driver software for National Instruments 73 xx motion controllers and the NI SoftMotion Controller. You can use NI-Motion to create motion control applications using the included...

Chapter 1 Introduction to NI-Motion NI-Motion User Manual 1-2 ni.com Software and Hardware Interaction Figure 1-1. NI Motion Control Hardware and Software Interaction Note The last block in Figure 1-1 is not applicable to the NI SoftMotion Controller. NI Motion Controller Architecture This section i...

Chapter 1 Introduction to NI-Motion NI-Motion User Manual 1-4 ni.com Figure 1-2 illustrates the physical architecture of the NI motion controller hardware. Figure 1-2. Physical NI Motion Controller Architecture Tip Because the NI SoftMotion Controller is not a hardware device, information about its ...

Chapter 1 Introduction to NI-Motion © National Instruments Corporation 1-7 NI-Motion User Manual The control loop handles closing the position/velocity loop based on feedback, and it defines the response and stability of the system. For stepper systems, the control loop is replaced with a step gener...

Chapter 1 Introduction to NI-Motion NI-Motion User Manual 1-8 ni.com Figure 1-6. NI SoftMotion Controller Functional Architecture for Ormec NI SoftMotion Controller for CANopen When you use the NI SoftMotion Controller with a CANopen device, you can daisy chain up to 15 drives together and connect t...

Chapter 1 Introduction to NI-Motion © National Instruments Corporation 1-9 NI-Motion User Manual Figure 1-7. NI SoftMotion Controller Functional Architecture for CANopen In this configuration, the I/O and the control loop execute on the CANopen drive. The NI SoftMotion Controller uses an NI-CAN devi...

© National Instruments Corporation 2-1 NI-Motion User Manual 2 Creating NI-Motion Applications This chapter describes the basic form of an NI-Motion application and its interaction with other I/O, such as a National Instruments data and/or image acquisition device. Creating a Generic NI-Motion Appli...

Chapter 2 Creating NI-Motion Applications NI-Motion User Manual 2-2 ni.com Figure 2-1. Generic Steps for Designing a Motion Application Adding Measurements to an NI-Motion Application Figure 2-2 illustrates an expanded view of the topics covered in Part III, Programming with NI-Motion , of this manu...

© National Instruments Corporation II-1 NI-Motion User Manual Part II Configuring Motion Control Motion control is divided into two parts: configuration and execution. Part II of this manual discusses configuring the hardware and software components of a motion control system using NI-Motion. Part I...

© National Instruments Corporation 3-1 NI-Motion User Manual 3 Tuning Servo Systems When your motion control system includes a servo motor, you must tune and calibrate the system to ensure proper performance. This chapter covers general information about tuning and calibrating your servo system usin...

Chapter 3 Tuning Servo Systems NI-Motion User Manual 3-2 ni.com A properly tuned servo system exhibits overshoot as shown in Figure 3-1. Figure 3-1. Properly Tuned Servo Motor Behavior The amount of time required for the motors to settle on the commanded position is called the settling time . By tun...

Chapter 3 Tuning Servo Systems NI-Motion User Manual 3-4 ni.com PID Loop Descriptions The following are common variables relating to the PID control loop. Kp (Proportional Gain) The proportional gain (Kp) determines the contribution of restoring force that is directly proportional to the position er...

Chapter 3 Tuning Servo Systems NI-Motion User Manual 3-6 ni.com Velocity feedforward is an open-loop compensation technique and cannot affect the stability of the system. However, if you use too large a value for Vff, following error can reverse during the constant velocity portion, thus degrading p...

Chapter 3 Tuning Servo Systems © National Instruments Corporation 3-7 NI-Motion User Manual Ga Ga is the Amplifier Gain. Kt Kt is the Torque Constant of the motor. Kt is represented in Newton Meters per Amp. 1/J 1/J represents the motor plus load inertia of the motion system. Ke Ke represents the co...

© National Instruments Corporation III-1 NI-Motion User Manual Part III Programming with NI-Motion You can use the C/C++ functions and LabVIEW VIs, included with NI-Motion, to configure and execute motion control applications. Part III of this manual covers the NI-Motion algorithms you need to use a...

© National Instruments Corporation 4-1 NI-Motion User Manual 4 What You Need to Know about Moves This chapter discusses the concepts necessary for programming motion control. Move Profiles The basic function of a motion controller is to make moves. The trajectory generator takes in the type of move ...

Chapter 4 What You Need to Know about Moves NI-Motion User Manual 4-2 ni.com Figure 4-1. Trapezoidal Move Profile S-Curve The acceleration and deceleration portions of an s-curve motion profile are smooth, resulting in less abrupt transitions, as shown in Figure 4-2. This limits the jerk in the moti...

Chapter 4 What You Need to Know about Moves © National Instruments Corporation 4-3 NI-Motion User Manual • Contoured Move —Is a user-defined move; you generate the trajectory, and the points loaded into the motion controller are splined to create a smooth profile The motion controller uses the speci...

Chapter 4 What You Need to Know about Moves NI-Motion User Manual 4-4 ni.com grouping axes into coordinate spaces. Using a multi-start automatically starts all axes virtually simultaneously. To simultaneously end the moves, you must calculate the move constraints to end travel at the same time. In c...

Chapter 4 What You Need to Know about Moves © National Instruments Corporation 4-5 NI-Motion User Manual NI 73 xx Time Base Velocity and acceleration values are loaded in counts/s, RPM, RPS/s, steps/s, and so on, which are all functions of seconds or minutes. However, the trajectory generator update...

Chapter 4 What You Need to Know about Moves NI-Motion User Manual 4-8 ni.com You can calculate the maximum velocity with the following equation: where Vmax = 20 MHz for servos 8 MHz for steppers on a NI 7350 controller 4 MHz for steppers on a NI 7330, NI 7340, or NI 7390 motion controller and is con...

Chapter 4 What You Need to Know about Moves © National Instruments Corporation 4-9 NI-Motion User Manual You can calculate the minimum acceleration increment with the following formula: where Amin = 1/65,536 counts/sample 2 or steps/sample 2 Ts = sample period in seconds per sample For a typical ser...

Chapter 4 What You Need to Know about Moves © National Instruments Corporation 4-11 NI-Motion User Manual You can calculate the maximum RPS/s using the following equation: where Amax = 32 counts/sample 2 Ts = sample period in seconds per sample R = counts or steps per revolution and is constrained a...

Chapter 4 What You Need to Know about Moves NI-Motion User Manual 4-12 ni.com Note If the distance of the move is too small, it may not be possible to reach the commanded maximum move constraints. In such instances, NI-Motion adjusts the move constraints lower to reach the commanded position. NI 73 ...

Chapter 4 What You Need to Know about Moves © National Instruments Corporation 4-13 NI-Motion User Manual NI 73 xx Arc Move Limitations The following are limitations to the velocity and acceleration of arc moves. Arc moves must use the following equations or an NIMC_invalidVelocityError is generated...

Chapter 4 What You Need to Know about Moves NI-Motion User Manual 4-14 ni.com Timing Loops National Instruments recommends that you use the loop timings discussed in the following sections. Status Display When you are displaying status information to the user, such as position, move status, or veloc...

© National Instruments Corporation 5-1 NI-Motion User Manual 5 Straight-Line Moves A straight-line move executes the shortest move between two points. Position-Based Straight-Line Moves Position-based straight-line moves use the specified target position to generate the move trajectory. For example,...

Chapter 5 Straight-Line Moves © National Instruments Corporation 5-5 NI-Motion User Manual C/C++ Code The following example code is not necessarily complete, and may not compile if copied exactly. Refer to the examples folder on the NI-Motion CD for files that are complete and compile as is. 1D Stra...

Chapter 5 Straight-Line Moves © National Instruments Corporation 5-7 NI-Motion User Manual // Error Handling nimcHandleError; // NIMCCATCHTHIS: // Check to see if there were any modal errors if (csr & NIMC_MODAL_ERROR_MSG){ do { // Get the command ID, resource ID, and the error code of the // mo...

Chapter 5 Straight-Line Moves © National Instruments Corporation 5-11 NI-Motion User Manual Algorithm Figure 5-4 is a generic algorithm applicable to both C/C++ and VI code. Figure 5-4. Velocity-Based Straight-Line Move Algorithm

Chapter 5 Straight-Line Moves © National Instruments Corporation 5-13 NI-Motion User Manual LabVIEW Code Figure 5-6. Velocity-Based Straight-Line Move in LabVIEW C/C++ Code The following example code is not necessarily complete, and may not compile if copied exactly. Refer to the examples folder on ...

Chapter 5 Straight-Line Moves © National Instruments Corporation 5-17 NI-Motion User Manual flex_read_csr_rtn (boardID,&csr); } while (csr & NIMC_MODAL_ERROR_MSG); } else // Display regular error nimcDisplayError(err,0,0); return ;// Exit the Application } Velocity Profiling Using Velocity O...

© National Instruments Corporation 6-1 NI-Motion User Manual 6 Arc Moves An arc move causes a coordinate space of axes to move on a circular, spherical, or helical path. You can move two-dimensional vector spaces in a circle only on a 2D plane. You can move a 3D vector space on a spherical or helica...

Chapter 6 Arc Moves NI-Motion User Manual 6-2 ni.com To move axes in a circular arc, the motion controller needs the following information: • Radius —Specifies the distance from the center of the arc to its edge • Start Angle —Orients the arc on its plane using the starting point as an axis to spin ...

Chapter 6 Arc Moves © National Instruments Corporation 6-3 NI-Motion User Manual Figure 6-3. Positive and Negative Travel Angles Arc Move Algorithm Figure 6-4. Circular Arc Move Algorithm 1 Positive Travel Angle 2 Negative Travel Angle 1 2 Load Velocity Start Motion Load Acceleration/ Deceleration P...

Chapter 6 Arc Moves © National Instruments Corporation 6-7 NI-Motion User Manual flex_read_error_msg_rtn (boardID,&commandI D,&resourceID, &errorCode); nimcDisplayError(errorCode,commandID,res ourceID); // Read the communication status register flex_read_csr_rtn (boardID,&csr); } whi...

Chapter 6 Arc Moves © National Instruments Corporation 6-13 NI-Motion User Manual // Get the command ID, resource ID, and the error code of the // modal error from the error stack on the device flex_read_error_msg_rtn (boardID,&commandI D,&resourceID, &errorCode); nimcDisplayError(errorC...

© National Instruments Corporation 7-1 NI-Motion User Manual 7 Contoured Moves A contoured move moves an axis or a coordinate space of axes in a pattern that you define. The trajectory generator on the motion controller is not used during a contoured move. The controller takes position data in the f...

Chapter 7 Contoured Moves NI-Motion User Manual 7-2 ni.com The difference between absolute contouring and relative contouring is how the points in the buffer are treated. The previous example was of an absolute contour move. A relative contour move treats the points as deltas according to the follow...

Chapter 7 Contoured Moves NI-Motion User Manual 7-4 ni.com All contoured moves are relative, meaning motion starts from the position of the axis or axes at the time the contouring move starts. This behavior is similar to the way arc moves work. Depending on the operation mode you use, you can load a...

© National Instruments Corporation 8-1 NI-Motion User Manual 8 Reference Moves Use reference moves to move the axes to a known starting location and orientation. Reference functions include Find Reference, Check Reference, Wait Reference, Read Reference Status, Load Reference Parameters, and Get Ref...

Chapter 8 Reference Moves NI-Motion User Manual 8-2 ni.com Reference Move Algorithm Figure 8-1. Find Reference Move Algorithm Load Velocity Load Jerk Load Acceleration/ Deceleration Find Reference Typically a Find Home Find Reference Typically a Find Index MoveConstraints Loop Waiting for Find Compl...

© National Instruments Corporation 9-1 NI-Motion User Manual 9 Blending Moves Use blending moves to create continuous motion between two or more move segments. Blending Blending, also called velocity blending, superimposes the velocity profiles of two moves to maintain continuous motion. Blending is...

Chapter 9 Blending Moves NI-Motion User Manual 9-2 ni.com There are three ways you can start the second move in a blend: • Superimpose the two moves by starting the second move as the first move starts to decelerate • Start the second move after the first profile is complete • Start the second move ...

Chapter 9 Blending Moves © National Instruments Corporation 9-3 NI-Motion User Manual Blend after First Move Is Complete Blending moves after the first move is complete causes the first move segment to come to a complete stop before starting the profile of the second segment, as shown in Figure 9-3....

Chapter 9 Blending Moves NI-Motion User Manual 9-4 ni.com Blend after Delay You can blend two moves after a delay at the end of the first move, as shown in Figure 9-4. Figure 9-4. Blending after a Delay Blending in this manner is useful if you want to start two move segments after a deterministic de...

© National Instruments Corporation 10-1 NI-Motion User Manual 10 Electronic Gearing and Camming Use electronic gearing or camming to synchronize the movement of one or more slave axes to the movement of a master device, which can be an encoder, ADC, or the trajectory of another axis. The movement of...

Chapter 10 Electronic Gearing and Camming NI-Motion User Manual 10-4 ni.com Changing a gear ratio on-the-fly during absolute gearing allows you to quickly synchronize the slave axis with the master axis. Note When the gear ratio is changed on-the-fly, the slave axis moves at full torque to the new p...

Chapter 10 Electronic Gearing and Camming NI-Motion User Manual 10-8 ni.com Camming Electronic camming operates similarly to electronic gearing in that the move distance of an axis is proportional to the move distance of its master device. Camming differs from gearing in how the master/slave ratio i...

Chapter 10 Electronic Gearing and Camming NI-Motion User Manual 10-12 ni.com Camming Table When a camming operation is active, the slave axis follows a profile that is established using a list of master and slave positions pairs, called the camming table. Refer to Table 10-1 for an example of a camm...

Chapter 10 Electronic Gearing and Camming © National Instruments Corporation 10-13 NI-Motion User Manual 2,000 counts in the opposite direction of the conveyor belt at half the speed that the conveyor belt is traveling at. Figure 10-10 shows the move profile of the first and second move segments. Fi...

Chapter 10 Electronic Gearing and Camming © National Instruments Corporation 10-15 NI-Motion User Manual Figure 10-13. Gear Ratio Change Figure 10-14 shows that when the master reaches position 6000, the slave axis moves back the original position, and the camming cycle begins again. Figure 10-14. C...

Chapter 10 Electronic Gearing and Camming © National Instruments Corporation 10-17 NI-Motion User Manual Master Offset If the material and welding point are not initially aligned, as shown in Figure 10-16, the master offset must be applied to consider the position difference. Figure 10-16. Misaligne...

Chapter 12 Synchronization NI-Motion User Manual 12-2 ni.com Table 12-1 shows the availability of breakpoint modes on each NI motion controller. Note If you are using a data or image acquisition device with your motion control system, be aware that the NI SoftMotion Controller does not support the R...

Chapter 12 Synchronization NI-Motion User Manual 12-8 ni.com Single Position Breakpoints Single position breakpoints execute one breakpoint per enabling. Single Position Breakpoint Algorithm Figure 12-3 shows the basic algorithm for implementing single position breakpoints. Figure 12-3. Single Posit...

Chapter 12 Synchronization NI-Motion User Manual 12-12 ni.com } Sleep (10); // Check every 10 ms } while (!(axisStatus & NIMC_POS_BREAKPOINT_BIT)); // Wait for breakpoint to be triggered } return ;// Exit the Application ////////////////////// // Error Handling nimcHandleError; // NIMCCATCHTHIS:...

Chapter 12 Synchronization NI-Motion User Manual 12-16 ni.com return ;// Exit the Application /////////////////////////////////////////////////// // Error Handling // nimcHandleError; // NIMCCATCHTHIS: // Check to see if there were any Modal Errors if (csr & NIMC_MODAL_ERROR_MSG){ do { // Get th...

Chapter 12 Synchronization © National Instruments Corporation 12-39 NI-Motion User Manual Position Breakpoints Using RTSI You can use the Select Signal function to route position breakpoints using one of the RTSI lines. In this case, the motion controller triggers the external device at a given posi...

© National Instruments Corporation 13-1 NI-Motion User Manual 13 Torque Control To maintain constant torque or force, the sensor that returns the feedback to the motion controller must return a value proportional to the torque or force. The motion controller operates torque-control and position-cont...

Chapter 13 Torque Control NI-Motion User Manual 13-8 ni.com Monitoring Force You can use this second force-feedback mode if you have a position sensor on the motor, in addition to the torque sensor. The control loop on the motion controller closes the position and velocity loops as usual. Use MAX to...

Chapter 13 Torque Control NI-Motion User Manual 13-14 ni.com Speed Control Based on Analog Value In a system where a feed roll must run at speeds based on an input voltage, the algorithm to maintain the speed consists of reading the analog voltage connected to one of the analog channels on the motio...

Chapter 14 Onboard Programs NI-Motion User Manual 14-2 ni.com Using Onboard Programs with NI 73 xx Motion Controllers You can use the real-time operating system on the NI 73 xx motion controller to run custom programs. This functionality allows you to offload some motion-specific tasks from the host...

Chapter 14 Onboard Programs © National Instruments Corporation 14-3 NI-Motion User Manual Figure 14-1. Onboard Program Priority Note If you continuously poll data from the host, the onboard program gets preempted and has less time to run. To keep this from happening, insert a small delay in the poll...

Chapter 14 Onboard Programs NI-Motion User Manual 14-8 ni.com Running, Stopping, and Pausing Onboard Programs Use the Run Program, Stop Program, and Pause/Resume Program functions to run, stop, and pause an onboard program that resides in the onboard memory of a motion controller. Running an Onboard...

Chapter 14 Onboard Programs © National Instruments Corporation 14-9 NI-Motion User Manual You can resume an onboard program with a function call from the host or from another running onboard program. Note It is not possible for an onboard program to resume itself. Tip Similarly to the Stop Program f...

Chapter 14 Onboard Programs NI-Motion User Manual 14-14 ni.com CheckError; return ;// Exit the Application ////////////////////// // Error Handling nimcHandleError; // NIMCCATCHTHIS : // Check to see if there were any Modal Errors if (csr & NIMC_MODAL_ERROR_MSG){ do { // Get the command ID, reso...

Chapter 14 Onboard Programs © National Instruments Corporation 14-19 NI-Motion User Manual ////////////////////// // Error Handling // nimcHandleError; // NIMCCATCHTHIS : // Check to see if there were any Modal Errors if (csr & NIMC_MODAL_ERROR_MSG){ do { // Get the command ID, resource ID, and ...

Chapter 14 Onboard Programs NI-Motion User Manual 14-20 ni.com Onboard Program Algorithm Figure 14-10 shows an onboard program waiting for an I/O line to go active before starting a move. Figure 14-10. Using Labels with Onboard Programs Start Move Set a Label Wait for Move Event Signal Jump to Label...

Chapter 14 Onboard Programs NI-Motion User Manual 14-24 ni.com // Read the communication status register flex_read_csr_rtn (boardID,&csr); } while (csr & NIMC_MODAL_ERROR_MSG); } else // Display regular error nimcDisplayError(err,0,0); return ;// Exit the Application } Math Operations NI-Mot...

Chapter 14 Onboard Programs © National Instruments Corporation 14-25 NI-Motion User Manual Figure 14-12. Reading an Indirect Variable Using indirect variables can be very useful in looping in onboard programs, as well as dynamically changing the input values to functions. Onboard Buffers You can use...

Chapter 14 Onboard Programs NI-Motion User Manual 14-34 ni.com Onboard Subroutines You can create subroutines to run as onboard programs and execute them from within an onboard program. Algorithm Figure 14-19 shows an onboard program algorithm that checks the I/O line state to determine which onboar...

Chapter 14 Onboard Programs NI-Motion User Manual 14-42 ni.com Automatically Starting Onboard Programs You can configure the onboard program to start automatically without calling the Run Program function. The onboard program runs as soon as the motion controller exits the reset state. To use this f...

© National Instruments Corporation IV-1 NI-Motion User Manual Part IV Creating Applications Using NI-Motion You can combine the moves, input/output, and other functionality discussed in Part III, Programming with NI-Motion , to create complete motion control applications. The following chapters show...

© National Instruments Corporation 15-1 NI-Motion User Manual 15 Scanning The goal of the scanning application is to inspect a wafer under a fixed laser. Multiple detectors collect the scattered laser light and feed the data to an analysis system that maps any defects. The wafer rests on an XY stage...

Chapter 15 Scanning © National Instruments Corporation 15-7 NI-Motion User Manual Blending Straight-Line Move Segments Blending the straight-line move segments enables continuous motion, which decreases the cycle time of the scan. The cycle time is much faster because the motors are not forced to st...

Chapter 15 Scanning © National Instruments Corporation 15-13 NI-Motion User Manual return ;// Exit the Application // Error Handling nimcHandleError; // NIMCCATCHTHIS : // Check to see if there were any Modal Errors if (csr & NIMC_MODAL_ERROR_MSG){ do { // Get the command ID, resource ID, and th...

© National Instruments Corporation 16-1 NI-Motion User Manual 16 Rotating Knife The purpose of this application is to cut a web with a rotating knife. The blade must cut precisely between labels on the web. Because the web material can stretch under certain conditions, it is not enough to cut the we...

© National Instruments Corporation A-1 NI-Motion User Manual A Sinusoidal Commutation for Brushless Servo Motion Control Sinusoidal commutation allows you to use less expensive servo motor drives with NI motion controllers that support this feature. Phase Initialization When the system is first powe...

Appendix A Sinusoidal Commutation for Brushless Servo Motion Control NI-Motion User Manual A-2 ni.com Direct Set Direct set is an initialization method where the controller sets the current position as the specified phase angle. This initialization method is recommended only for a custom system with...

Appendix A Sinusoidal Commutation for Brushless Servo Motion Control © National Instruments Corporation A-3 NI-Motion User Manual Troubleshooting Hall Effect Sensor Connections Complete the following steps if you have problems with Hall effect sensor connections. 1. Check the manuals that shipped wi...

Appendix B Initializing the Controller Programmatically NI-Motion User Manual B-2 ni.com 10. Call halt on all axes to activate them. Use the Stop Motion VI with S top Type (Decel) set to Halt stop . 11. Configure capture and compare settings. Use the VIs on the Motion I/O palette to configure the ca...

© National Instruments Corporation C-1 NI-Motion User Manual C Using the Motion Controller with the LabVIEW Real-Time Module Using NI-Motion on a real-time (RT) system is designed to be almost transparent for anyone familiar with NI-Motion. Using NI-Motion with RT requires the following hardware and...

Appendix C Using the Motion Controller with the LabVIEW Real-Time Module © National Instruments Corporation C-3 NI-Motion User Manual To remove the mapped motion controller, browse to My System under Device and Interfaces . Right-click the mapped controller and select Unmap Remote Device . You shoul...

© National Instruments Corporation D-1 NI-Motion User Manual D Technical Support and Professional Services Visit the following sections of the National Instruments Web site at ni.com for technical support and professional services: • Support —Online technical support resources at ni.com/support incl...

© National Instruments Corporation I-1 NI-Motion User Manual Index A absolute contouring, 7-4acceleration feedforward, 3-6acceleration in counts/s 2 , 4-8 acceleration in RPS/s, 4-9acquiring data algorithm, 11-2C/C++ code, 11-4data path, 11-1LabVIEW code, 11-4 adding, measurements to an NI-Motion ap...