Introduction

As intelligent manufacturing and warehouse automation continue to develop rapidly, towing AGVs are becoming increasingly important in industrial logistics systems. In practical applications, whether the AGV drive system can provide sufficient traction force directly affects transportation efficiency, startup stability, and long-term operational reliability.

As a professional manufacturer focusing on AGV drive systems, AGV drive wheels, servo motors, and intelligent motion control solutions, Yikong Intelligent has accumulated extensive engineering experience in heavy load AGV applications, towing robots, warehouse logistics systems, and industrial automation equipment.

In many non-standard AGV projects, drive system selection is still based mainly on motor power or rated torque, which can easily lead to the following problems:

• Motor overload during startup

• Insufficient traction force causing towing failure

• Slow acceleration response

• Excessive structural impact during docking

• Premature failure of buffer systems

Therefore, AGV drive system design should be based on classical mechanics calculations, combining traction force, rolling resistance, acceleration load, wheel torque, and buffer structures into a complete engineering calculation model.

2. AGV System Load Definition

The foundation of towing AGV power calculation is the total system mass:

M = m_AGV + m_load

Where:

• m_AGV: AGV self-weight

• m_load: Payload or towing cart mass

• M: Total system mass

The total gravitational load is:

W = M × g

Where g = 9.8 m/s².

In practical projects, Yikong Intelligent usually recommends reserving additional load margin for heavy-duty towing AGV systems to ensure stable operation under long-term continuous working conditions.

3. Driving Resistance Analysis

During straight-line operation, AGVs mainly need to overcome rolling resistance and acceleration inertia.

3.1 Rolling Resistance

Rolling resistance is generated by wheel-ground deformation:

Ff = f × M × g

Where f is the rolling resistance coefficient, generally ranging from 0.03 to 0.06.

For warehouse AGVs operating on epoxy floors or concrete surfaces, Yikong Intelligent typically optimizes wheel material and drive wheel structure to reduce rolling resistance and improve transmission efficiency.

Under turning conditions or uneven surfaces, rolling resistance may increase by 5%–10%, so engineering safety margins must be considered during drive wheel selection.

3.2 Air Resistance

For indoor AGV systems operating at low speed:

Fw = 0.5 × rho × Cd × A × v²

This resistance is usually negligible in industrial AGV engineering calculations.

3.3 Acceleration Inertial Resistance

During startup or acceleration:

Fj = M × a

If rotational inertia from motors and reducers is included:

Fj = M × a + Σ(Ji × alpha_i / ri)

However, simplified engineering calculations generally use:

Fj ≈ M × a

3.4 Total Required Traction Force

Therefore, the total traction force required by the AGV is:

F_total = M × a + f × M × g

This equation is one of the core foundations for AGV drive wheel and servo motor selection.

4. Drive Wheel Force and Torque Relationship

The AGV drive wheel converts motor torque into actual ground traction force.

4.1 Basic Mechanical Formula

F = T / r

Where:

• F: Ground traction force

• T: Drive wheel output torque

• r: Drive wheel radius

This explains why compact drive wheel systems with smaller wheel diameters can often achieve higher traction force under the same motor torque conditions.

Yikong Intelligent’s AGV drive wheel systems are optimized for traction efficiency, compact structure, and heavy load capacity, making them suitable for towing AGVs, differential AGVs, AMRs, and outdoor mobile robots.

4.2 Multi-Drive Wheel Systems

For systems with n drive wheels:

T_total = n × T_wheel

Considering gearbox efficiency:

T_wheel = (T_motor × i × eta) / n

Where:

• i: Reduction ratio

• eta: Transmission efficiency (typically 0.9–0.95)

5. Acceleration and Motor Torque Verification

A qualified AGV design must verify not only whether the vehicle can move, but also whether it can achieve the target acceleration under load conditions.

5.1 Acceleration Formula

a = (F_total - f × M × g) / M

Expanded form:

a = (n × T / r - f × M × g) / M

This formula is critical for evaluating AGV acceleration performance.

5.2 Starting Torque Requirement

The startup stage is the most demanding condition for AGV motors:

T_start = ((M × a + f × M × g) × r) / n

For heavy-duty towing AGVs, Yikong Intelligent typically recommends reserving additional startup torque margin to prevent overload under full-load conditions.

5.3 Steady-State Running Torque

During constant-speed operation:

T_steady = (f × M × g × r) / n

6. Engineering Example Analysis

Example parameters:

M = 100 kg

r = 0.015 m

f = 0.05

n = 2

Target acceleration:

a = 0.5 m/s²

6.1 Rolling Resistance

Ff = 100 × 9.8 × 0.05 = 49 N

6.2 Total Traction Force

F_total = 100 × 0.5 + 49 = 99 N

6.3 Single Wheel Torque Requirement

T = (99 × 0.015) / 2 = 0.7425 N·m

Engineering Conclusion

This example demonstrates that AGV drive system design must be based on actual acceleration targets and real load conditions rather than relying only on motor rated power.

In actual industrial projects, Yikong Intelligent often combines servo motors, planetary gear reducers, AGV drive wheels, and motor controllers into integrated drive solutions to improve overall system stability and traction performance.

7. Spring Buffer System Design

During docking or anti-collision processes, towing AGVs require spring buffer systems to absorb impact energy.

7.1 Hooke’s Law

F = k × x

Where:

• k: Spring stiffness

• x: Compression displacement

7.2 Multi-Spring Load Distribution

For systems using n_s springs:

F_spring = (M × g) / n_s

Spring stiffness:

k = F_spring / x

7.3 Design Principles

An effective AGV buffer system should:

• Evenly distribute impact load

• Maintain sufficient compression stroke

• Prevent rigid impact transmission to the vehicle frame

8. Conclusion

The core of towing AGV drive system design is the balance between traction force, resistance, inertia, and structural buffering capability.

For industrial AGV applications, motor power alone cannot determine whether a drive system is suitable. Engineers must comprehensively evaluate:

• Total vehicle mass

• Target acceleration

• Wheel radius

• Gear reduction ratio

• Drive wheel torque

• Rolling resistance

• Buffer structure design

As an AGV drive system manufacturer, Yikong Intelligent continues to provide customized drive wheel systems, servo motors, differential drive solutions, and heavy load AGV power systems for intelligent logistics and industrial automation applications worldwide.