KUKA LBR Med Medical Robot Integration Guide

KUKA LBR Med Medical Robot Integration Guide

Product positioning: Robot components rather than complete machines

Unlike LBR iiwa, which is aimed at the industrial field, KUKA LBR Med (models 7 R800 and 14 R820) is a special type of "Robot Component" - it is integrated by medical device manufacturers into fixed, permanently installed, or mobile medical devices and marketed as a medical device in the form of a complete system. The document clearly states that this user manual is intended for medical device manufacturers and cannot be directly handed over to end users as a user manual.

LBR Med undertakes two types of tasks in medical devices: tool guidance (including navigation) and action repetition. Typical applications include surgical navigation, biopsy positioning, and other scenarios. Its system composition includes: a robot body with built-in Inside Electrical Med media flange, KUKA Sunrise Cabinet Med controller (available in AC and DC versions), smartPAD teaching pendant (optional), connecting cables, and KUKA Sunrise. OS Med software.

A hard indicator that must be kept in mind is that the operating life of the robot system is 10000 operating hours. This value should be used as the basic input for the overall life design and service cycle planning of the machine.

Compliance Framework: CB Certification and Partial Completion of Machinery

LBR Med has been tested according to the CB Scheme and accompanied by a CB testing certificate to demonstrate compliance with the standards listed in the certificate. There are two red lines in the document that are particularly noteworthy for integration engineers:

Software version binding: Only software components with version numbers listed in the CB test report are compatible with each other and allowed to be installed together. Install software components that deviate from the report, and the CB test report will be invalidated.

Prohibition of modification: Any modification or adaptation of LBR Med and its components (including attachments) is not allowed, as modification will result in the invalidation of CB test certificates and compliance statements.

At the level of the Machinery Directive, LBR Med belongs to partially completed machinery (Appendix II B of 2006/42/EC), and can only be put into operation after being integrated into medical devices and meeting the requirements of the Medical Device Directive/Regulation through compliance assessment procedures. The "General Safety and Performance Requirements" in Appendix I of 2017/745/EU (MDR) are the responsibility of medical device manufacturers. The AC version of the controller comes with EMC and low voltage directive CE markings, while the DC version comes with EMC and RoHS directive CE markings.

List of Expected Uses and Prohibited Items

Among the abuse scenarios listed in the document, the following are directly related to the clinical environment and must be explicitly excluded in the risk assessment:

Non medical applications (such as industrial use)

During the operation of mobile medical equipment, the mobile device itself

Robots move simultaneously with their external axes (such as linear units)

Operating in an oxygen rich environment and near flammable materials (such as anesthetics)

Operating near MRT (magnetic resonance) equipment and strong magnetic fields

Used in conjunction with defibrillators (robots do not have defibrillator safety)

Robots used as Applied Parts

Connect the BF or CF type application parts defined in IEC 60601-1 directly to the robot without appropriate intermediate insulation

Power the application part through data cables (such as PoE)

Unmanned operation, operated by non-medical personnel/patients/third parties

The underlying reason for these limitations lies in the electrical and electromagnetic characteristics of LBR Med, and the insulation concept section below will provide the technical roots.

Technical parameter comparison and medical differentiation design

Parameter item LBR Med 7 R800 LBR Med 14 R820

Workspace volume 1.7 m ³ 1.8 m ³

Posture repeatability (ISO 9283) ± 0.1 mm ± 0.15 mm

Self weight approximately 25.5 kg, approximately 32.3 kg

Rated load 7 kg 14 kg

Maximum operating range 800 mm 820 mm

Protection level IP54 IP54

Maximum shaft torque A1/A2 176 Nm 320 Nm

Controller Sunrise Cabinet Med Sunrise Cabinet Med

Torque sensor measurement accuracy ± 2% ± 2%

Compared with the industrial version of IIWA, the medical version has three significant differences: firstly, the operating environment temperature has been narrowed to+5 ° C to 35 ° C (45 ° C for the industrial version), and the requirements for atmospheric pressure (500-1060 hPa) and maximum installation altitude of 3000 m have been increased; Secondly, the appearance is uniformly in traffic white (RAL 9016), which meets the visual standards of medical environments; Thirdly, the maximum length of the cable is only 7 meters (with five options of 1/1.8/2.3/3/7 meters and no extension allowed), which is much shorter than the industrial version's 15 meters.

The two Cartesian motion abilities are consistent: translational speed of 3.0 m/s, rotational speed of 400 °/s, and translational acceleration of 10 m/s ². The document specifically reminds that the maximum axial acceleration and acceleration given correspond to the rated load condition, and the actual allowable value may be higher under light load - in force control and trajectory planning, the measured constraints of the controller must be used as the standard.

Surface temperature and IEC 60601-1 Table 23

This is a key data unique to the medical version: after using a 50-150 µ m transparent anti-static polyethylene sterile cover and running continuously for seven hours at an ambient temperature of 30 ° C, the surface temperatures of each PDS (electric drive system) cover plate were measured to be PDS1=39.0 ° C, PDS2=47.5 ° C, PDS3=49.1 ° C, PDS4=48.7 ° C, and then the values remained constant. The ambient temperature and the highest surface temperature can be seen as a linear relationship. When the ambient temperature does not exceed 28 ° C, it meets the requirements of Table 23 of IEC 60601-1 for the highest surface temperature; Manufacturers must verify compliance through continuous or intermittent operation testing for complete machine applications exceeding 28 ° C.

Media Inside Electrical Med and 1 MOPP Insulation Concept

The media flange is the core interface integrated by LBR Med, weighing 262 g, and the hole position complies with DIN ISO 9409-1-50-7-M6. Robots can only operate with this media flange. It provides two power supplies (maximum 48 V DC/8 A via X651, maximum 48 V DC/5 A via X76), analog signal and CAT5 data interface, and internal connectors. The maximum number of insertions and removals of the Tool Connector is 100 times, and the minimum bending radius of the outgoing cable is 5.85 mm.

The insulation concept is the safety core of the entire electrical design. The document assumes that the external environment of the robot is pollution level 2 (it can operate in a pollution level 3 environment under IP54), and the insulation achieved is designed according to 1 MOPP (Patient Protection Measures). The key rules include:

Insulated paths 1-10 are located inside the robot and media flange, with the second layer of protection provided by PE;

The insulation paths 11-14 are located inside the tool connector, and the second MOPP must be achieved by the medical device manufacturer by properly integrating the tool connector into the customer's tool - this is the manufacturer's non transferable responsibility;

The shielding layers of CTR1 and CTR2 must not be connected to PE or grounded enclosures, otherwise the achieved quantity of 1 MOPP will not meet the requirements;

The CTR3 shielding layer between the controller casing and the media flange casing has been internally connected to the flange casing;

The exposed cable end must be insulated, otherwise it may cause short circuit and damage to the media flange;

IP54 cannot be maintained without connecting all connecting cables, and appropriate sealing measures must be implemented between the flange and the tool.

This set of rules explains the root cause of the "BF/CF application section prohibits direct connection" in the previous abuse list: the robot body only meets the requirements of the B-type application section.

Stop distance data and braking testing mechanism

The document provides STOP 0 data according to Appendix B of DIN EN ISO 10218-1. Taking LBR Med 14 R820 as an example, the results of the traditional four axis assessment method (100% extension, 100% POV, maximum load) are: A1 axis 5.742 °/0.188 s, A2 axis 5.998 °/0.200 s, A3 axis 9.323 °/0.198 s, A4 axis 3.162 °/0.092 s.

The medical version has added seven axis flange space stop distance data, which has more clinical reference value: when STOP 0 is triggered from rest, the maximum stop distance of the entire machine flange is only 0.152 mm (A2 axis dominant, 13.9 ms); When moving at 400.0 mm/s, the complete machine stops at a distance of 22.05 mm (133.8 ms); When moving at 598.0 mm/s, it is 41.80 mm (144.8 ms). For surgical scenes with limited space, this millimeter level data directly determines the setting of the protected space.

Special reminder: The STOP 0 data for axes 1-2 are measured values. To avoid risks, it is recommended to multiply the stopping distance and time results by a safety factor of 2.0. Brake wear is related to the number of STOP 0 triggers, and it is recommended to check the stopping distance at least once a year.

The medical version has a qualitative difference in brake testing: the brake test cannot be turned off by the system integrator, and the system enforces periodic brake testing. If not executed, the system will shut down. The document also states that the brake is only applied as a safety measure in the event of a malfunction, and the system will provide a warning message in advance to indicate torque decay before reaching the minimum allowable holding torque - medical device manufacturers must include the time occupation of periodic brake testing in application development.

Installation, startup, and daily operation and maintenance

Installation specification: Both models should use 4 M10x30-8.8 hexagon socket bolts (torque 45 Nm) uniformly, and tighten them in diagonal sequence in multiple stages. After running for 100 hours, tighten them again. The positioning holes are Ø 6 H7 with two depths of 15mm, and the fastening threads are M10x1.5 with four depths of 20mm. We recommend Misumi LANAN6-P6-B5-L5 (cylindrical) and LANDN6-P6-B5-L5 (flat side) positioning pins. The bending radius of the fixed cable laying shall not be less than 45 mm, and an additional 4 mm ² grounding conductor (M4 ring cable terminal) shall be laid according to DIN EN 60204 requirements to achieve low resistance equipotential connection, in order to meet the EMC level of Group 1 of Class B in EN 55011.

Absolute precision model installation constraint: The gravity direction during calibration must be consistent with that during operation - a deviation of ≤ 5 ° will only result in loss of pose accuracy, while a deviation greater than 5 ° will prevent the controller from starting properly. The W/A/B/C information on the label must be interpreted according to the KUKA agreement (ZYX intrinsic Euler angle) and must be entered in Sunrise. Wordbench.

The pre startup functional testing is consistent with the industrial version framework (emergency stop, enable switch, panic position, mode selection switch, safety output shutdown capability), but the panic position test requires holding down the panic position for 3 seconds. If smartPAD is configured as pluggable, at least one external emergency stop device that is always accessible must be installed. When starting incompletely, alternative risk minimization measures (safety fences, warning signs, main opening and closing locks, etc.) must be taken and recorded.

Maintenance cycle table:

Periodic tasks

Daily (before operation) visual inspection for damage and liquid leakage; Perform brake testing; Check the operational readiness status (controller error); cleaning robot

Replace all worn stickers within a maximum of 6 months; Check the fastening of the connectors; Check for cable damage; Check the tightness of the threaded connection

1 year inspection of emergency stop device availability; Measure leakage current and grounding conductor resistance; SmartPAD All Enable Switch Function Test

Periodic electrical testing must be carried out by the user in accordance with IEC 62353 and is limited to personnel who have received specialized training - this is the key point that distinguishes the medical version from the industrial version, which states' no maintenance required for intended use '.

The boundary between cleaning, disinfection, and sterilization

The cleaning specification in the medical environment is extremely strict: only wet cloth is allowed to wipe, and spray is strictly prohibited (spray may form combustible mixture or penetrate into the equipment); Cleaning agents are limited to 96% ethanol and medical wiping alcohol (undiluted); Disinfectants are limited to specified formulas such as phenolic derivatives (6% concentrated solution+94% water), aldehydes (undiluted or 12%+88% water), aldehydes+quaternary ammonium salts (10%+90% water), etc. Residual disinfectants and cleaning agents must be thoroughly removed to avoid contamination and infection risks for patients; Clean all parts that come into contact with the patient before each use.

An absolute ban: Robots are not allowed to sterilize. If the intended use requires direct operation in a sterile environment, medical device manufacturers must define corresponding measures (such as using appropriate Drape sterile covers), and the applicability of Drape must be included in the risk management assessment - it must not restrict the robot's mobility, affect the manual guidance mode (no additional external force generated after stretching), cause damage or displacement during movement, and not cause overheating.

List of Key Risk Management Points for Medical Device Manufacturers

The document appendix provides a fairly complete risk management framework, with the following core items that must be implemented item by item:

Liquid accumulation: There are gaps and open cavities on the structure of the robot that can accumulate liquid, and measures to prevent condensation and drainage need to be evaluated.

Application component determination: Evaluate whether non application parts that may come into contact with patients must meet the requirements of B/BF/CF according to clause 4.6 of IEC 60601-1.

Controller isolation: Patients are not allowed to touch the controller and a casing must be installed. Only maintenance personnel can use tools to open it.

Leakage current: Measure the leakage current of the whole machine according to the classification of application parts to ensure that it does not exceed the limit.

Vibration: Running vibration transmission may cause discomfort to patients and should be minimized.

Unexpected stop and fault stop behavior: If risk management allows, safety stop 1 should be prioritized over brake stop (safety stop 0) in emergency situations to avoid unnecessary wear and tear on the brake.

Single fault safety: Security configuration must be correctly configured in Sunrise. WGbench Med based on its own application risk management.

Alarm system: An alarm system that complies with IEC 60601-1-8 can be established based on LBR Med data.

PEMS network integration: Analyze three types of threats: data error flow (CRC/timestamp/packet counter, timing watchdog), network overload, and direct/indirect network access (complete isolation on the network side, system reinforcement, physical access protection), and record protective measures.

Clamping hazard: Assess the squeezing risk of operators at potential clamping points and configure corresponding safety functions.

Strong magnetic fields and implants: The electromagnetic fields generated by motors and magnets may cause dysfunction of implants such as pacemakers, and evaluation and measures must be taken.

Absolute accuracy model failure: Transportation stress, improper installation, excessive process force, collision, aging and wear, maintenance and replacement can all cause accuracy loss. Simply resetting to zero is not enough to restore absolute accuracy and must be externally verified.

Additional load of energy supply system: When adding an energy supply system to the application section, ensure that the rated load does not exceed 7 kg or 14 kg, and evaluate its impact on collision detection, manual guidance, and impedance motion.

Maintenance and retirement

The maintenance of robots and media flanges can only be carried out by KUKA customer service personnel, and internal module maintenance is limited to KUKA trained personnel only. Before carrying out live work, it is necessary to strictly follow the five step safety method: power off → prevent accidental restart → verify no power → ground and short-circuit → shield or block adjacent live parts. After the controller is powered off, wait for at least 5 minutes before verifying the power (there has been a general warning for residual voltage exceeding 60 V).

When replacing the A3/A5 slot plate, use M2.5x6-A4-70-KLF stainless steel Torx screws (torque 0.5 Nm). Old screws must not be reused, and the slot plate and robot must not tilt - friction edges will interfere with the torque sensor. When installing the ES adapter to secure the energy supply system, the screw insertion depth should not exceed 4 mm, and it is strictly prohibited to use magnets or magnetic components to fix it. Magnetic fields can interfere with the sensor system under the slot plate and damage the robot.

Before returning for repair, a hygiene declaration must be filled out and attached to the goods (refer to BVMed official website information) - products that appear or are actually contaminated may pose a health hazard to contact personnel due to infectious biological materials. During long-term storage, the media flange must be equipped with a contact protection cap and packaged in a dust-proof ESD bag. If necessary, desiccants should be added.