Wheeled Humanoid Robot Motion Control System

Wheeled Humanoid Robot Motion Control System

Open · Efficient · Intelligent

Document version: V1.0 Hardware platform: iNexBot industrial robot controller (RK3588 platform) Application areas: dual-arm collaboration, human-robot collaboration, robot algorithm validation, multi-robot coordinated control, advanced control theory research, industrial manufacturing, healthcare, commercial services, logistics and warehousing, education and research


1. Company Introduction

iNexBot Technology is a technology company focused on the R&D of robot motion control systems. With independently developed advanced control algorithms and extensive industry experience, it is committed to bringing wheeled humanoid robot technology into industrial and service applications. The iNexBot motion control system delivers precise control of key body parts such as the dual arms, waist and neck, giving robots exceptional flexibility and adaptability.


2. Product Overview

The iNexBot Technology wheeled humanoid robot motion control system is designed for complex scenarios and supports multiple configuration options to meet diverse application needs. The platform is built on the ABOX-6116 industrial controller (Rockchip RK3588 + Debian 11 / Ubuntu 20.04) and ships standard with dual robot control engines (14 axes or 12 axes total, expandable up to 32 axes). It exposes the full-chain NexDroid OpenAPI, allowing users to develop their own algorithms end to end, from the joint control layer up to trajectory planning. The modular design offers strong compatibility and seamless integration with third-party wheel bases, dexterous hands and vision systems.

The platform targets universities, research institutes and corporate laboratories, providing a high-realtime, highly open hardware foundation and software ecosystem for research scenarios such as dual-arm coordinated motion control, advanced dynamics algorithms and intelligent control strategies, as well as real-world industrial and service deployments.


3. Product Features

3.1 Dual-Arm Collaborative Control System

  • Supports two dual-arm configurations:
    • Dual 6-axis collaborative robots (2×6 axes)
    • Dual 7-axis collaborative robots (2×7 axes)
  • 7-axis configuration: the wrist supports SRS structures (spherical-revolute-spherical) or cross-intersecting structures, flexibly selectable according to the task
  • High-precision trajectory planning and collision detection
  • Dual-arm collaborative operation modes supporting:
    • Symmetric synchronized motion
    • Asymmetric coordinated manipulation
    • Object handover and transfer
    • Hybrid force-position control

3.2 Waist Control System

  • Multiple configuration options:
    • 1 axis (rotation)
    • 3 axes (X/Y/Z translation)
    • 4 axes (4 serial joints)
    • 6 axes (3 translation + 3 rotation)
  • Dynamic balance compensation
  • Load-adaptive capability

3.3 Neck Control System

  • Single-axis rotation design
  • Expandable to multi-DOF configurations
  • Vision following support

3.4 Chassis Control System

ItemDescription
Chassis structureDual differential drive wheels + auxiliary caster wheels
Communication protocolCAN bus, direct control of the differential wheels

4. Application Scenarios

The iNexBot Technology wheeled humanoid robot motion control system is widely used in the following areas:

4.1 Industrial Manufacturing

  • Automotive assembly lines: precision tasks requiring dual-arm collaboration, such as door installation and dashboard assembly
  • Electronics manufacturing: fine operations such as circuit board assembly and component soldering
  • Machining: auxiliary tasks such as tool changing and parts handling

4.2 Healthcare

  • Surgical assistance: high-precision dual arms assist doctors with delicate operations
  • Rehabilitation training: stable support and assistance
  • Pharmaceutical dispensing: precise operations in sterile environments

4.3 Commercial Services

  • Food and beverage service: tasks such as table setting and drink preparation
  • Hotel reception: luggage handling and concierge services
  • Retail display: product presentation and interactive demonstrations

4.4 Logistics and Warehousing

  • Shelf replenishment: dual-arm collaboration for goods picking and placement
  • Parcel sorting: efficient sorting with vision system support
  • Heavy material handling: the waist support system carries heavier loads

4.5 Education and Research

  • As a teaching and research platform, the robot supports experiments and development in fields such as artificial intelligence and robotics

4.6 Dual-Arm Assembly

  • The master arm holds the workpiece while the slave arm holds the tool
  • Compliant assembly strategy based on torque sensing
  • Hybrid force-position control

4.7 Dual-Arm Handling

  • Coordinated gripping of large or irregularly shaped workpieces
  • Master-slave pose-constrained motion
  • Optimized load distribution between the arms

4.8 Dual-Arm Polishing/Buffing

  • The master arm positions the workpiece while the slave arm performs the polishing
  • Constant-force tracking control
  • Trajectory coordination compensation

4.9 Algorithm Validation Platform

  • Rapid deployment of new control laws (MPC/RL/adaptive)
  • Dynamics parameter identification
  • Dual-arm impedance/admittance control
  • Human-robot physical interaction (pHRI) algorithms

5. Product Advantages

5.1 High-Performance Processing Platform

  • Powered by the Rockchip RK3588 processor (8 cores: 4×Cortex-A76 + 4×Cortex-A55, up to 2.4GHz, built-in 6 TOPS NPU expandable to 20 TOPS); see Section 7, Hardware Specifications
  • Onboard LPDDR5 8GB RAM + 64GB eMMC storage
  • Fanless aluminum-magnesium alloy body, operating temperature -20°C ~ 70°C

5.2 Realtime Motion Control

  • EtherCAT communication for high speed and precision; slave synchronization jitter <20μs
  • Control cycle down to 1ms (position loop/velocity loop), minimum 250μs
  • Self-developed motion control algorithms supporting dual-arm collaboration

5.3 Flexible Configuration Options

  • Waist supports multiple axis configurations (1~6 axes) for different task needs
  • Dual arms compatible with both 6-axis and 7-axis robots for greater operational diversity
  • Independent dual-arm configurations supporting serial multi-joint, SCARA and custom configurations
  • DH parameters open and configurable, modifiable online

5.4 Exceptional Openness and Compatibility

Communication protocols:

  • EtherCAT (master/slave)
  • PROFINET RT/IRT
  • Ethernet/IP
  • Modbus TCP/RTU
  • CANopen
  • OPC-UA

For physical interfaces see Section 7.2; for software protocols see Section 8.3.

Third-party device integration:

  • Wheeled chassis (via CAN bus)
  • Dexterous hands (Modbus/TCP, Modbus/RTU protocols)
  • Vision systems (EtherNet)

Standard API interfaces:

  • ROS/ROS2 support
  • Python, C#, C++ SDKs

6. Motion Control System Specifications

6.1 Basic Parameters

ItemSpecification
Dual-arm axes14 axes total (left arm 7 axes + right arm 7 axes), or 12 axes total (left arm 6 axes + right arm 6 axes)
Maximum axes32 axes (total system capacity, incl. external axes)
Control cycle1ms (position loop/velocity loop), minimum 250μs
EtherCAT synchronizationDistributed clocks (DC), slave synchronization jitter 20μs
Multi-axis synchronization error< 50μs
Interpolation modesPTP / Line / Arc / Spline / FLYBY
Coordinate systemsJoint coordinates, robot coordinates, tool coordinates, user coordinates
Robot configurationsIndependent dual-arm configurations; serial multi-joint, SCARA and custom configurations; 7-axis wrists support SRS / cross-intersecting structures
DH parametersOpen and configurable, modifiable online
Repeat positioning accuracy±0.005mm
Maximum velocity2m/s
Maximum acceleration5m/s²
Force control resolution0.1N
Torque control accuracy±0.5% FS

6.2 Dual-Arm Collaboration Modes

FeatureDescription
Collaboration modesDual-robot coordination (master-slave / loosely coupled / tightly coupled)
Synchronization accuracyStart/stop fully synchronized between the two robots, based on EtherCAT distributed clocks
Interference zonesDual-arm interference zone definition and collision protection
Coordinate system associationSlave arm workspace definable in the master arm's base coordinate system
Coordination commandsDual-robot point-to-point (CoordPTP), dual-robot line (CoordLine), dual-robot arc
Independent operationEach robot's parameters/programs/variables are independent; synchronized start/stop also supported

6.3 Control Modes

ModeSupport LevelDescription
Joint position modePosition loopJoint angle targets are given; the controller plans and executes the trajectory
Joint velocity modeVelocity loopJoint velocity commands issued directly; open-loop or closed-loop
Joint torque/current modeCurrent loopJoint torque commands issued directly (requires matching servo support)

7. Hardware Specifications

7.1 Controller

ItemParameter
ModelABOX-6116 industrial controller
CPURockchip RK3588, 8 cores (4×Cortex-A76 + 4×Cortex-A55, up to 2.4GHz)
GPUMali-G610 MC4
NPU6 TOPS (INT8); optional M.2 RK1820 compute card expands to 20 TOPS
MemoryOnboard LPDDR5 8GB
StorageOnboard 64GB eMMC; optional M.2 2280 SATA3 SSD
Network5× Gigabit Ethernet (4× Intel i210 + 1× RTL8211F)
Wi-Fi / BTOnboard dual-band 2.4G/5G Wi-Fi 6 + Bluetooth 5.0
4G LTE1× Mini-PCIe, supports LTE 4G modules (optional)
Operating systemUbuntu + iNexBot control system
PowerDC 12~24V ±10%, power consumption ≤20W, overcurrent/overvoltage/reverse-polarity protection
CoolingFanless design, aluminum-magnesium alloy enclosure + aluminum profile heatsink
Dimensions170mm × 112mm × 48mm (excluding mounting bracket)
Weight1.5kg
MountingWall mount / DIN-Rail
Operating temperature-20°C ~ 70°C

7.2 Communication and Control Interfaces

InterfaceQtyDescription
Gigabit Ethernet5 ports4× Intel i210 + 1× RTL8211F; 1 port is used as the EtherCAT master with distributed clock (DC) synchronization
USB 3.02 ports1 port shared with OTG; each port supports 5V@2A
USB 2.01 portPeripheral connection
HDMI1 portUp to 8K (7680×4320) output
RS2322 channelsIsolated, 3.5mm Phoenix terminal
RS4852 channelsIsolated, 3.5mm Phoenix terminal, supports Modbus RTU
Isolated DI8 channelsDry/wet contact auto-switching, isolation voltage 2500Vrms
Isolated DO8 channelsNPN/PNP switchable (DIP switch), isolation voltage 2500Vrms
PWM output4 channelsLight source control, supports external hardware trigger (DC 5~24V), max 1A per channel (optional)
Micro SIM1 slotSIM card for 4G LTE module

7.3 Servo Drive System (Selection Recommendations)

OptionRecommended ModelDescription
EtherCAT servoEtherCAT joint modules compliant with the CIA402 standard-
Encoder typeAbsolute encoders supported

7.4 Teach Pendant (Optional)

ItemParameter
ModelT30 robot-specific teach pendant
Screen8-inch TFT full touchscreen, 1024×600
Operating systemLinux + QT
FunctionsTeach programming, parameter configuration, status monitoring, program debugging

7.5 Environmental Requirements

ItemRequirement
Power supplyDC 12~24V ±10% (≤20W; 12V 40W adapter recommended)
Operating temperature-20°C ~ 70°C
Servo rated currentSelected according to the manipulator specifications
Host computerWindows / Linux workstation with a Gigabit Ethernet port

8. Software Platform Specifications

8.1 System Architecture

System architecture diagram

8.2 Secondary Development Interfaces (NexDroid OpenAPI)

Dual-arm control:

Interface CategoryContentDevelopment Language
Joint controlJoint position/velocity/torque command issuingC#, Python, TCP Socket
Kinematics interfacesForward kinematics (FK) input/output accessC#, Python, TCP Socket
Trajectory planningCustom trajectory generation and path issuingC#, Python, TCP Socket
Admittance controlSimultaneous target position + stiffness parameter (K) + damping parameter (D) issuing for compliant interactionC#, Python, TCP Socket
State feedbackRealtime reading of joint position, velocity, torque and IO statesC#, Python, TCP Socket
Variable systemGlobal/local variable read/writeC#, Python, TCP Socket
Servo controlServo power on/off, alarm resetC#, Python, TCP Socket
DH parametersOnline modification of robot DH parametersTeach pendant / configuration file
Configuration managementController configuration import/exportFile system

Chassis control:

CategoryInterfaceDescription
Chassis managementEnableEnables the chassis into a controllable state
E-stopImmediately stops chassis motion
Error clearClears chassis faults/alarm states
Control mode switchingRemote control mode, navigation mode and idle mode
Direct controlVelocity/angular velocity issuingLinear and angular velocities issued via protocol for forward/reverse driving, turning and in-place rotation
Navigation controlPath trackingIssues a path point sequence for tracking; forward and reverse paths supported
Path replacementReplaces the current path points during operation
ReplanningTriggers path replanning
In-place rotationRotates in place to a specified heading in navigation mode
Stop navigationAborts the current navigation task
Status and configurationCurrent status queryQueries realtime chassis status (position, velocity, mode, etc.)
Set odometry parametersConfigures odometry resolution, wheelbase and other parameters
Set heading angleSets/corrects the chassis current heading angle

8.3 Communication Protocols

ProtocolPurposeCharacteristics
Port 7000 protocolCore control protocol (JSON over TCP)Query/issue joint coordinates, variables, IO; single-point and continuous trajectories
Custom TCP communicationHost computer ↔ controllerServer/Client modes; 9 process numbers concurrent
Modbus TCP/RTUPLC/sensor integrationFlexible master/slave configuration
OPC-UAData acquisition/monitoring systemsStandardized industrial interconnection
EtherNet/IPAllen-Bradley PLCsCIP protocol support
FinsTCPOmron PLCsCommand/response format

Physical-layer communication performance: EtherCAT minimum cycle 100μs, PROFINET IRT minimum cycle 250μs, communication jitter 20μs; see Section 7.2.

8.4 ROS / ROS2 Ecosystem Support

ModuleStatusDescription
ROS driver nodeIntegratableEncapsulates ROS joint_state_publisher / trajectory_msgs via the port 7000 protocol
ROS2 driver nodeIntegratableROS2 nodes built on the NexDroid OpenAPI, with lifecycle management support
URDF modelAvailable on requestURDF descriptions auto-generated from DH parameters
TF treeIntegratablePublishes joint transforms in realtime → builds a complete TF tree
MoveIt adaptationIntegratableExposes joint_trajectory_action / follow_joint_trajectory
ROS2 ControlIntegratableInterfaces with the ros2_control framework via the hardware interface layer

Note: ROS/ROS2 drivers require secondary development integration based on the NexDroid OpenAPI; iNexBot provides interface documentation and example code.

ToolPurpose
Visual Studio / VS CodeC# host application development
Python 3.8+Algorithm prototyping and validation
ROS / ROS2Robot software ecosystem integration
Lua scriptsRapid logic development on the teach pendant
TCP/UDP debugging toolsCommunication protocol validation

9. Open Dynamics Interface Specifications

9.1 Open Interfaces

InterfaceAccessDescription
Joint angle θRealtime read (1ms)Current joint angles of the 7 axes
Joint velocity θ̇Realtime read (1ms)Current joint angular velocities of the 7 axes
Joint torque τRealtime read (1ms)Current joint torques of the 7 axes (requires servo feedback)
Joint command τ_cmdWriteJoint torque commands issued directly in torque mode
DH parameter tableRead/writeStandard DH / modified DH parameters, modifiable at runtime
Mass/inertia parametersRead/writeLink masses, centers of mass and inertia tensors
Forward kinematicsCallθ → TCP pose; built-in or user-defined
Inverse kinematicsCallTCP pose → θ; built-in or user-defined
Jacobian matrix J(q)ComputeGeometric/analytic Jacobian

9.2 User-Defined Algorithm Entry Points

Replacement PointReplaceable FunctionInterface Form
Joint control lawPID → sliding mode / adaptive / MPC / RLJoint position/velocity/torque commands
Forward kinematicsDefault algorithm → customθ → XYZ+RPY
Inverse kinematicsDefault algorithm → customXYZ+RPY → θ
Trajectory planningTrapezoidal/S-curve → customPath point sequence → time-parameterized trajectory
Dynamics feedforwardGravity/Coriolis compensation addedτ_ff = M(q)q̈ + C(q,q̇) + G(q)

9.3 Data Acquisition and Logging

FunctionSupport
High-frequency state loggingJoint position/velocity/torque, 1ms sampling period
Host computer data streamRealtime push via port 7000 (1ms level)
Offline logsLocal controller logs, exportable for analysis, format compatible with .csv

10. Precision Calibration Solution — NexAutoCali Automatic Calibration System

The iNexBot wheeled humanoid robot solution integrates the self-developed NexAutoCali robot automatic calibration system, providing full-parameter precision calibration for 7-axis and 6-axis humanoid arms to ensure sub-millimeter repeat positioning accuracy in dual-arm collaborative operations.

Detailed documentation: see NexAutoCali Automatic Calibration System.

10.1 Full-Parameter Calibration

Full-parameter calibration is currently the optimal way to achieve high-fidelity alignment between the robot's theoretical model and the physical unit. It supports gear ratio calibration, zero-point calibration, link length calibration and full-parameter calibration, unlocking the equipment's own accuracy limits. After full-parameter calibration, TCP accuracy can be improved from 3mm to 0.5mm — an improvement of up to 500%.

10.2 Full Coverage of 7-Axis / 6-Axis Robots

Compatible with 7-axis collaborative arms (SRS / cross-intersecting structures) and 6-axis collaborative/industrial arms, and with the independent dual-arm configuration of wheeled humanoid robots; custom model adaptation available on request.

10.3 Fully Automated Workflow

Leveraging iNexBot's drive-control strengths, the entire workflow is automated end to end — automatic measurement point planning → automatic execution → automatic laser tracker measurement → algorithm computation → calibration result output — greatly improving ease of use and reliability.

10.4 Fast and Efficient

  • Streamlined operation logic reduces training and usage difficulty
  • Quick-mount design: software/hardware environment ready in 5 minutes
  • Optimized calibration flow: a 50-point full-parameter calibration takes < 5 minutes typically

10.5 Highly Integrated All-in-One System

The system integrates laser tracker measurement, robot motion control, automatic calibration/measurement point planning, fully automatic calibration/test process control and algorithm computation into one package — a single software suite handles all calibration and measurement work with no additional programming.

10.6 Full-Feature Testing

  • Built-in robot calibration modules: gear ratio calibration, zero-point calibration, link length calibration, full-parameter calibration
  • Built-in 14-indicator robot performance test module
  • Fully compliant with the national standard GB/T 12642—2013 / ISO 9283:1998

10.7 Multi-Brand Tracker Compatibility

Already compatible with the API Radian Core and other high-precision laser trackers; more brands are continuously being added.

10.8 Calibration Process Overview

Connect robot → read parameters → automatically plan measurement points → run tests automatically → data acquisition → algorithm computation → generate calibration results

11. Packaging Contents

No.ComponentQtyRemarks
1Controller main unit1ABOX-6116, with Debian 11 / Ubuntu 20.04
2T30 teach pendant (optional)1Including 5m connecting cable
3Power cable1DC 12~24V terminal connector
4EtherCAT network cable2CAT5e or above
5Technical documentation USB drive1Including development manuals, SDK and protocol documentation
6NexDroid OpenAPI development kit1C# / Python example code

The following are public access links to related documents in the iNexBot Technology knowledge base (doc.inexbot.com):

12.1 Product Documentation

DocumentLink
iNexBot Industrial Robot Controller Datasheethttps://doc.inexbot.com/产品资料/控制系统/工业机器人控制器C1201
iNexBot Industrial Robot Controller (Compact) Datasheethttps://doc.inexbot.com/产品资料/控制系统/工业机器人控制器C1102
iNexBot Industrial Robot Controller (Multi-Axis) Series Datasheethttps://doc.inexbot.com/产品资料/控制系统/工业机器人控制器C2200系列
T30 Teach Pendant Datasheethttps://doc.inexbot.com/产品资料/控制系统/T30示教器
NexAutoCali Automatic Calibration Systemhttps://doc.inexbot.com/产品资料/精度标定/自动标定系统NexAutoCali
Supported Servo Modelshttps://doc.inexbot.com/技术资料/支持的伺服型号
Supported Robot Typeshttps://doc.inexbot.com/技术资料/支持的机器人类型
Supported External Axis Typeshttps://doc.inexbot.com/技术资料/支持的外部轴类型

12.2 Operation Manuals

DocumentLink
Motion Control Commandshttps://doc.inexbot.com/操作手册/24.03版本/运动控制类指令
Robot DH Parameter Descriptionhttps://doc.inexbot.com/操作手册/24.03版本/机器人DH参数说明
Multi-Robot and Dual-Robot Collaborationhttps://doc.inexbot.com/操作手册/24.03版本/多机与双机协作
New Dual-Robot Featureshttps://doc.inexbot.com/操作手册/24.03版本/新双机功能
Multi-Robot Coordination Commandshttps://doc.inexbot.com/操作手册/24.03版本/多机协调类指令
Interference Zoneshttps://doc.inexbot.com/操作手册/24.03版本/干涉区
External Axis User Manualhttps://doc.inexbot.com/操作手册/24.03版本/外部轴使用手册
Independent Axis Controlhttps://doc.inexbot.com/操作手册/24.03版本/独立轴控制
Servo Response Timehttps://doc.inexbot.com/操作手册/24.03版本/伺服响应时间
System Function Debugging Manualhttps://doc.inexbot.com/操作手册/24.03版本/系统功能调试手册
Target Configuration Calculation Commandshttps://doc.inexbot.com/操作手册/24.03版本/计算目标形态指令
Tool Frame Calibration Manualhttps://doc.inexbot.com/操作手册/24.03版本/工具手标定手册
User Coordinate Calibration Manualhttps://doc.inexbot.com/操作手册/24.03版本/用户坐标标定手册

12.3 Secondary Development and Communication Protocols

DocumentLink
Port 7000 User Manualhttps://doc.inexbot.com/操作手册/24.03版本/7000端口
TCP Communication Function Manualhttps://doc.inexbot.com/操作手册/24.03版本/TCP通讯功能手册
Modbus Function User Manualhttps://doc.inexbot.com/操作手册/24.03版本/Modbus功能使用手册
OPC-UA Parametershttps://doc.inexbot.com/操作手册/24.03版本/OPC-UA参数
EIP Function Operating Instructionshttps://doc.inexbot.com/操作手册/24.03版本/EIP功能操作说明
FINSTCP User Manualhttps://doc.inexbot.com/操作手册/24.03版本/FINSTCP使用手册
Lua Tutorialhttps://doc.inexbot.com/操作手册/24.03版本/Lua教程
PC Simulation Software Tutorialhttps://doc.inexbot.com/操作手册/24.03版本/PC支持仿真软件使用教程
Communication Protocol & Address Codeshttps://doc.inexbot.com/技术资料/通讯协议&地址码

12.4 Process Applications

DocumentLink
Vision Processhttps://doc.inexbot.com/操作手册/24.03版本/视觉工艺
Conveyor Tracking Process Manualhttps://doc.inexbot.com/操作手册/24.03版本/传送带跟踪工艺手册
Welding Processhttps://doc.inexbot.com/操作手册/24.03版本/焊接工艺
Palletizing Processhttps://doc.inexbot.com/操作手册/24.03版本/码垛工艺
Laser Cutting Processhttps://doc.inexbot.com/操作手册/24.03版本/激光切割工艺

Disclaimer

The ROS/ROS2 support, open dynamics interfaces and other features listed in this datasheet are based on the NexDroid OpenAPI platform; some integration work must be completed by the user following the provided development documentation and example code. The actual level of feature implementation is subject to the technical annex of the contract. RK3588 platform parameters are reference values; actual performance may vary with system configuration and operating environment.

文档反馈

Wheeled Humanoid Robot Motion Control System-Embodied Humanoid-iNexBot