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AGV需要多少扭矩? 具有工程标准的基于有效负载的答案

AGV需要多少扭矩

AGV需要多少扭矩? 具有工程标准的基于有效负载的答案

Engineers designing Automated Guided Vehicles (AGV) 和自主移动机器人 (抗菌药物耐药性) routinely ask one question early in the project: how much torque does the drive motor actually need? The answer is never a single number. It depends on vehicle mass, acceleration target, slope angle, 轮径, floor friction, 从动轮数量, 变速箱速比, and the thermal duty cycle the motor must sustain. This guide breaks the question down by payload class, provides force-model formulas you can apply immediately, and grounds the recommendations in international motor standards (国际电工委员会 60034-1, NEMA MG 1) and manufacturer technical data from Maxon, Faulhaber, and Yaskawa.

无论您正在构建一个 50 kg indoor AMR or a 60-ton heavy-load transfer cart, the methodology below will get you to a defensible motor torque specification before you issue an RFQ.

Why Torque Sizing Determines AGV Success or Failure

Undersized torque causes motor stall under load, overheating during sustained operation, and failure to climb ramps. Oversized torque wastes battery capacity, increases wheel slip on smooth floors, and raises BOM cost without performance gain. In production environments, AGV reliability is rarely limited by control software — it is limited by the mechanical interaction between motor torque, wheel traction, 和地板条件 [1].

The torque requirement is not a single value but a profile across operating conditions. An AGV that moves smoothly on flat epoxy may stall on a 3% ramp. A motor that handles straight-line cruising may fail during in-place rotation, which typically demands two to five times the straight-line torque in differential-drive configurations [5].

桌子 1. Consequences of Torque Mismatch
健康)状况Torque Too LowTorque Too HighCorrectly Sized
Acceleration from standstillStall, motor overheat, navigation timeoutWheel slip, encoder feedback lossSmooth launch, stable speed ramp
Ramp climbing (3–5% grade)Vehicle stops on slope, rollback riskExcess current draw, battery drainConsistent speed on grade
In-place rotation (differential drive)Cannot complete turn, caster dragTire scuffing, floor damagePredictable turn, minimal wear
Sustained operation (8+ 小时)Thermal trip, winding insulation degradationEnergy waste, oversized controller costStable temperature within insulation class

The Quick Answer: Torque by Payload Class

If you need a ballpark before diving into formulas, the table below maps typical AGV payload classes to per-wheel continuous torque, recommended motor type, voltage platform, 和变速箱速比. These values assume 2 driven wheels, polyurethane tires on smooth concrete (Crr = 0.02), 0.5 米/秒²加速度, flat floor, and a safety factor of 1.5. They are starting points, not final specifications — always validate with the force model in the next section.

桌子 2. Quick-Reference Torque by AGV Payload Class
有效负载等级Gross Mass (千克)Per-Wheel Continuous Torque (牛顿·米)电机类型电压变速箱比典型电机功率
Micro AMR (shelf-scanning, inventory)30–800.5–2.0BLDC 22–42 mm12–24 V DC10:1–20:130–100 W
Light AMR (goods-to-person)80–2002.0–5.0BLDC 42–57 mm24 在直流电15:1–30:1100–300 W
Medium AGV (pallet, 排序)200–5005.0–15.0BLDC 57–86 mm24–36 V DC20:1–50:1300–800 W
Heavy AGV (assembly line, hospital)500–3,00015.0–60.0BLDC 86–115 mm48 在直流电30:1–80:1800–2,000 W
Heavy-load transfer cart (钢, foundry)3,000–60,00060.0–300.0+2× BLDC 115–120 mm (dual motor)48–72 V DC30:1–80:1 (with brake gearbox)2× 1.5–3 kW

The torque values in Table 2 are per driven wheel. For a 2-wheel differential drive, the total tractive torque is double the per-wheel value. For a 4-wheel-drive configuration, divide the per-wheel value by 2 (assuming equal load distribution). Always recalculate using the formulas below for your specific operating conditions.

Force Model: Four Resistance Components

AGV drive torque is determined by the total resistance force the vehicle must overcome. The force model decomposes this into four components, each corresponding to a physical resistance source. This decomposition follows the methodology described in the MDPI Engineering Proceedings paper on motor parametric calculations for robot locomotion [9] and is consistent with the sizing approaches used by Oriental Motor [3] and iNetic Motion [4].

1. Rolling Resistance (Froll)

Rolling resistance is the force required to deform the tire and floor at the contact patch. It depends on the tire material, floor surface, and normal load. Polyurethane tires on smooth epoxy have the lowest rolling resistance; rubber tires on rough concrete have the highest.

桌子 3. Rolling Resistance Coefficients (Crr) by Wheel/Floor Combination
Wheel MaterialFloor TypeCrr 范围Typical AGV Application
Polyurethane (Shore 92A–95A)Smooth epoxy0.010–0.015Cleanroom, electronics factory
PolyurethanePolished concrete0.015–0.025仓库, distribution center
PolyurethaneConcrete with joints0.020–0.035Manufacturing floor
RubberEpoxy floor0.020–0.030医院, 食品加工
RubberRough concrete / asphalt0.035–0.060Outdoor transfer path
Nylon / VulkollanSteel rail / V-track0.005–0.010Heavy-load rail-guided AGV

Formula: Froll = m × g × Crr × cos(我)

在哪里 is gross vehicle mass (千克), = 9.81 米/秒², Crr is the rolling resistance coefficient, 和 is the slope angle. On flat ground, 因斯(0°) = 1, so the term simplifies to m × g × Crr.

2. Acceleration Force (Facc)

Newton’s second law: the force required to accelerate the vehicle’s mass from rest to target speed. This is typically the largest force component during startup.

Formula: Facc = m × a

在哪里 一个 is the target acceleration (米/秒²). AGV acceleration is usually 0.3–0.8 m/s² for stability. AMRs may reach 1.0 米/秒². Emergency deceleration can require 1.5–2.0 m/s², which produces the highest force transient.

桌子 4. Recommended Acceleration by AGV Type
AGV类型Normal Acceleration (米/秒²)Emergency Deceleration (米/秒²)笔记
Micro AMR0.5–1.01.5–2.0Light payload, rapid start-stop
Light AMR (goods-to-person)0.4–0.81.0–1.5Balance of speed and load stability
Medium AGV (pallet)0.3–0.60.8–1.2Prevent pallet shift during braking
Heavy AGV (assembly line)0.2–0.50.5–1.0Smooth ramp critical for precision loads
Heavy-load transfer cart0.1–0.30.3–0.5Liquid loads (molten metal) demand ultra-low jerk

3. Grade Resistance (Fgrade)

When the AGV operates on a ramp — loading dock approaches, floor transitions, or inclined transport paths — gravity adds a component parallel to the slope. This force can be substantial even on modest grades.

Formula: Fgrade = m × g × sin(我)

桌子 5. Grade Resistance at Common Ramp Slopes
SlopeAngle (度数)Fgrade per 1000 千克 (否)Typical Scenario
1%0.57°98Floor tolerance, barely perceptible
3%1.72°294Loading dock approach ramp
5%2.86°490Warehouse floor transition
8%4.57°783Parking garage ramp
10%5.71°977Outdoor transfer path, steep grade

一个 1,200 kg AGV on a 3% ramp must overcome 353 N of grade resistance alone — nearly equal to its rolling resistance on flat ground. If your AGV encounters ramps, grade resistance often becomes the dominant force component.

4. Turning Resistance (F转动) — Differential Drive Only

In differential-drive AGVs (two powered wheels, multiple casters), in-place rotation generates the highest torque demand. Caster wheels must pivot, creating significant scrub resistance. An engineering approximation from field data [5]:

Formula: Fspin = (2 × Froll × √( + )) / W

在哪里 W is wheel track width and L is vehicle length. 在实践中, rotation torque is 2–5× the straight-line torque, and it usually determines the peak torque rating of the motor.

Core Torque Formulas and Variables

Combining the four force components, the total driving force and wheel torque are calculated as follows. This formulation is consistent with the method described in the MDPI Engineering Proceedings paper [9] and the AGV Drive Wheel sizing guide [2].

Total Driving Force

Ftotal = Froll + Facc + Fgrade

(Turning resistance is evaluated separately as a peak condition, not added to the continuous force.)

Per-Wheel Torque

时间车轮 = (Ftotal × r车轮) / n驾驶

在哪里 r车轮loaded 车轮半径 (not the nominal radius — a polyurethane tire compresses 2–5 mm under load), 和 n驾驶 is the number of driven wheels sharing traction.

Motor-Side Continuous Torque

时间马达 = (时间车轮 × SF) / (i × η)

Where SF is the safety factor (1.25–1.5 for indoor, 2.0 for heavy industrial, 2.5 for safety-critical), 一世 is the gearbox reduction ratio, 和 或者 is the gearbox efficiency.

桌子 6. Gearbox Efficiency by Type and Stage Count
变速箱类型Stages效率 (或者)Typical Ratio Range间隙
行星式 (精确)1 阶段0.94–0.963:1–10:1< 5 弧分
行星式 (精确)2 stages0.88–0.9210:1–50:1< 5 弧分
行星式 (精确)3 stages0.82–0.8650:1–200:1< 7 弧分
Spur gear (parallel)1 阶段0.90–0.932:1–8:110–30 弧分
Worm gear (直角)1 阶段0.60–0.755:1–60:1不适用 (self-locking)

适用于 AGV 应用, two-stage planetary gearboxes are the most common choice because they offer the best balance of efficiency, 扭矩密度, and backlash. For an in-depth comparison of gearbox types, 看看我们的 spur gear motor vs. 行星齿轮马达 分析. Worm gearboxes are generally avoided in AGVs due to their low efficiency (which wastes battery capacity) and self-locking behavior (which prevents coasting and regenerative braking).

Power Check

P车轮 = Ftotal × v
P马达 = P车轮 / (或者 × η马达)

在哪里 v is target travel speed (多发性硬化症), and η马达 is the motor efficiency (0.85–0.92 for BLDC at rated load). This power figure should include a 30–50% margin for surge, braking hold, and ramp startup.

工作示例: 150 kg AMR and 1,200 kg AGV

例子 1: 150 kg AMR (Goods-to-Person Robot)

桌子 7. Step-by-Step Torque Calculation — 150 kg AMR
范围价值Calculation
1Gross mass (米)150 千克100 公斤有效负载 + 50 kg chassis
2加速 (一个)0.5 米/秒²Typical for goods-to-person AMR
3Slope angle (我)0° (flat)Indoor warehouse, no ramps
4Crr0.015PU tire on polished concrete
5Loaded wheel radius (r)0.10 米200 mm nominal, 5 mm compression
6Driven wheels (n)2差动驱动
7Froll22.1 否150 × 9.81 × 0.015
8Facc75.0 否150 × 0.5
9Fgrade0 否Flat ground
10Ftotal97.1 否22.1 + 75.0 + 0
11时间车轮 (per wheel)4.86 牛顿·米(97.1 × 0.10) / 2
12Safety factor applied6.55 牛顿·米4.86 × 1.35 (indoor)
13Gearbox ratio (一世)20:12-stage planetary
14Gearbox efficiency (或者)0.902-stage planetary
15时间马达 (continuous)0.36 牛顿·米6.55 / (20 × 0.90)
16Travel speed (v)1.5 多发性硬化症Goods-to-person target
17P马达 (和 40% margin)226 W → select 250 W(97.1 × 1.5) / (0.90 × 0.88) × 1.4

结果: 一个 150 kg AMR requires approximately 0.36 N·m continuous motor torque per drive wheel with a 20:1 行星齿轮箱. 一个 24在 BLDC 电机中 in the 200–300 W range with a 42–57 mm frame size is appropriate. 这 complete AGV motor selection guide provides additional payload classes and motor model recommendations.

例子 2: 1,200 kg AGV (Assembly Line Transport)

桌子 8. Step-by-Step Torque Calculation — 1,200 kg AGV
范围价值Calculation
1Gross mass (米)1,200 千克1,000 公斤有效负载 + 200 kg chassis
2加速 (一个)0.5 米/秒²Smooth launch for assembly parts
3Slope angle (我)1.72° (3% grade)Loading dock approach
4Crr0.020PU tire on industrial concrete
5Loaded wheel radius (r)0.10 米200 mm nominal, loaded
6Driven wheels (n)2Rear differential drive
7Froll235.4 否1,200 × 9.81 × 0.020 × cos(1.72°)
8Facc600.0 否1,200 × 0.5
9Fgrade353.2 否1,200 × 9.81 × 罪恶(1.72°)
10Ftotal1,188.6 否235.4 + 600.0 + 353.2
11时间车轮 (per wheel)59.4 牛顿·米(1,188.6 × 0.10) / 2
12Safety factor applied80.2 牛顿·米59.4 × 1.35
13Gearbox ratio (一世)30:12-stage planetary, 重负
14Gearbox efficiency (或者)0.882-stage planetary
15时间马达 (continuous)3.04 牛顿·米80.2 / (30 × 0.88)
16Travel speed (v)1.0 多发性硬化症Assembly line pace
17P马达 (和 50% margin)2,144 W → select 2× 1.5 千瓦(1,188.6 × 1.0) / (0.88 × 0.90) × 1.5

结果: 这 1,200 kg AGV requires approximately 3.04 N·m continuous motor torque per wheel with a 30:1 变速箱. A 48V BLDC motor in the 1–2 kW range (86–115 mm frame) is appropriate. Note that the grade resistance (353 否) contributes 30% of the total force — if the AGV operates only on flat ground, the required torque drops to 2.2 N·m and the power to 1,540 W. This highlights why you must size for the worst-case operating point, not the average.

For a deeper treatment of torque calculation methodology, including differential-drive turning torque and inertia matching, 看看我们的 AGV电机扭矩计算指南 with full force models and standard references.

基于有效负载的电机选择矩阵

The table below synthesizes the calculations from the worked examples and extends them across the full payload range. It assumes 2-wheel differential drive, polyurethane tires on smooth concrete, 0.5 米/秒²加速度, and includes both flat-ground and 3% grade scenarios.

桌子 9. AGV Motor Selection Matrix by Payload Class
范围有效负载等级
Micro AMRLight AMRMedium AGVHeavy AGVTransfer Cart
Gross mass (千克)501505001,2005,000
Target speed (多发性硬化症)1.51.51.01.00.5
Ftotal flat (否)32972468352,453
Ftotal 3% grade (否)812435291,1893,923
Per-wheel T (flat) (牛顿·米)1.64.912.341.8122.6
Per-wheel T (grade) (牛顿·米)4.112.226.559.4196.2
Safety factor1.51.351.51.52.0
时间马达 cont. (牛顿·米)0.30.71.83.414.5
电机功率 (W)50–100200–300500–8001,000–2,0002× 1,500–3,000
Motor frame (毫米)22–4242–5757–8686–115115–120 (双重的)
电压 (在直流电)12–242424–364848–72
Gearbox ratio10:1–20:115:1–30:120:1–50:130:1–80:130:1–80:1

For custom motor specifications outside these standard payload classes, GreenSky Power offers custom electric motor design with frame sizes from 22 mm to 120 毫米, voltage options from 12V to 72V DC, and integrated gearbox solutions.

热验证: 国际电工委员会 60034-1 Duty Cycles

Torque alone does not guarantee motor survival. The motor must sustain the required torque within its thermal limits over the actual duty cycle. 国际电工委员会 60034-1:2022 (版 15, published March 2026) defines ten duty cycle classifications, of which five are most relevant to AGV applications [7].

桌子 10. 国际电工委员会 60034-1 Duty Cycle Classifications for AGV Applications
IEC Class描述Thermal BehaviorAGV Application MatchTorque Derating
S1Continuous runningSteady-state temperature reachedConveyor-style AGV, 24/7 line operationNone — rated torque = continuous torque
S2Short-time dutyCools to ambient between runsBatch transport, long idle between movesCan exceed S1 torque by 1.5–2× for short bursts
S3Intermittent periodic dutyNo significant cooling between cyclesGoods-to-person AMR, cyclic pick-and-placeDepends on duty cycle % (ed = on-time / total cycle)
S4Intermittent with starting influenceStarting losses includedFrequent start-stop AGV (assembly line feeder)Starting current heats winding; derate 10–20% vs. S1
S5Intermittent with electric brakingBraking energy adds heatAGV with regenerative braking on rampsBraking energy must be dissipated or regenerated

Most AGV applications fall under S3 or S4 duty. The key distinction: if your AGV starts and stops frequently (typical cycle: 10 seconds moving, 20 seconds loading), the motor winding does not fully cool between cycles, and the continuous torque rating must cover the RMS torque over the full cycle, not just the peak.

RMS Torque Calculation

For intermittent duty, calculate the RMS torque over one complete cycle:

时间RMS = √[(T₁²×t₁ + T₂²×t₂ + … + 时间n²×tn) / (t₁ + t₂ + … + tn)]

The motor’s rated continuous torque must exceed TRMS at the operating ambient temperature. If TRMS exceeds the rated torque, the motor will overheat — even if the peak torque is well within the motor’s capability.

Thermal Derating by Ambient Temperature

Motor torque ratings in datasheets are specified at 25°C ambient (per Maxon standard specification 100/101) [11]. At higher ambient temperatures, the permissible continuous torque decreases.

桌子 11. Thermal Derating for BLDC Motors (Class B Insulation, 130℃)
环境温度额定电流 (%)额定扭矩 (%)笔记
25℃ (catalog baseline)100%100%Maxon/Faulhaber catalog values
40℃ (IEC standard ambient)85–90%85–90%Typical industrial environment
50℃70–75%70–75%Foundry, steel mill, hot warehouse
60℃50–55%50–55%Extreme environment; upgrade to Class F/H

If your AGV operates in a 40°C ambient (common in un-air-conditioned warehouses), you must derate the motor by 10–15%. A motor rated for 5 N·m continuous at 25°C delivers only 4.25–4.50 N·m at 40°C. For high-temperature environments, specify Class F (155℃) 或H级 (180℃) 绝缘, which allows 100% rated current up to 50°C ambient [12].

NEMA MG 1 Torque Classifications for AGV Motors

NEMA MG 1-2021 classifies motors into four design types based on torque characteristics and starting-load inertia. While NEMA standards are primarily used for AC induction motors, the torque classification framework is useful for understanding motor behavior under AGV startup conditions. IEC Design N and Design H classifications are roughly equivalent to NEMA Design B and C, 分别 [8].

桌子 12. NEMA MG 1 Design Types and AGV Relevance
NEMA DesignLocked Rotor Torque (% of full-load)Pull-Up Torque (% of full-load)Breakdown Torque (% of full-load)IEC EquivalentAGV 适用性
Design A100–200%100–140%200–250%Low starting torque; not ideal for AGV (load may stall on startup)
Design B (most common)150–200%100–140%200–250%IEC Design N通用型; adequate for AGVs with gearbox (gearbox multiplies starting torque)
Design C200–250%140–200%190–225%IEC Design H高启动扭矩; suitable for AGVs with heavy payloads and frequent starts
Design D275%+不适用 (high slip)Highest starting torque; used for heavy-load transfer carts with flywheel effect

For BLDC motors used in AGVs, the NEMA design classification is less directly applicable because BLDC motors are electronically commutated and their torque-speed curve is determined by the controller, not the rotor design. 然而, the concept of locked-rotor (开始) torque maps to the BLDC motor’s peak torque rating, which is typically 2–3× the continuous torque rating for 30–60 seconds before thermal protection activates.

The relationship between NEMA torque classifications and BLDC motor selection is discussed in our BLDC motor vs. 伺服电机 comparison, which covers how electronic commutation changes the torque-speed envelope.

Peak vs. 连续扭矩: Why Most Sizing Errors Happen Here

The single most common mistake in AGV motor selection is sizing for peak torque without validating continuous thermal performance. Motor datasheets advertise peak torque prominently because it is the higher number, but peak torque is only available for a limited duration (typically 30–60 seconds) before the winding reaches its thermal limit.

桌子 13. Peak vs. 连续扭矩: Motor Data Interpretation
范围定义Typical BLDC Ratio (Peak/Continuous)AGV Sizing Rule
连续扭矩 (额定)Torque the motor can deliver indefinitely without exceeding insulation class temperature1.0× (baseline)Must exceed TRMS of the duty cycle
峰值扭矩 (最大限度)Maximum torque before demagnetization or thermal trip2.0–3.0×Must exceed worst-case transient (加速度, ramp start, 转动)
堵转扭矩Torque at zero speed (motor held stationary at rated voltage)3.0–5.0×Never operate at stall; causes rapid overheating
Torque constant (Kt)Torque per unit current (N·m/A)Use to calculate required current: I = T / Kt

Maxon specifies that motor constants have tolerances of up to ±10% and change with motor temperature — catalog values apply at 25°C, and a warm motor produces less torque [11]. Faulhaber’s DC Motors Technical Information notes that for optimal motor operation, the required speed should be higher than half the no-load speed, and the load torque should be less than the maximum continuous torque [12]. Yaskawa’s SigmaSelect sizing software generates a comparison report between servo system capability and application requirements, explicitly separating peak and continuous operating points [13].

Practical rule: Size the continuous torque to cover the RMS torque of the duty cycle (including derating for ambient temperature), then verify that the peak torque covers the worst-case transient. If the peak/continuous ratio of your selected motor is less than 2.0×, you may need a larger motor even if the continuous torque appears adequate.

Gearbox Matching: Reflected Torque and Inertia

The gearbox does more than reduce speed and multiply torque. It also transforms the load inertia as seen by the motor, which affects control stability and acceleration response.

反射惯性

The load inertia reflected to the motor shaft is divided by the square of the gearbox ratio:

Ĵreflected = J加载 /

在哪里 Ĵ加载 is the vehicle inertia at the wheel and 一世 is the gearbox ratio. 一个 20:1 gearbox reduces the reflected inertia by a factor of 400, making the motor see a much smaller inertia. This is critical for servo-controlled AGVs where the inertia ratio affects tuning stability.

桌子 14. Recommended Inertia Match Ratios
控制类型Recommended J加载马达 比率Consequence of Exceeding
伺服 (闭环, FOC)< 5:1Oscillation, tuning difficulty, audible noise
步进机 (开环)< 10:1Lost steps, resonance at low speeds
BLDC with Hall sensors (速度环)< 10:1Sluggish response, speed droop under load

For AGV applications using BLDC motors with Hall-sensor feedback, an inertia ratio below 10:1 is generally acceptable because the velocity control loop does not require the precision of a position loop. For applications requiring precise positioning (例如, AGV docking), consider upgrading to a motor controller with encoder feedback and targeting an inertia ratio below 5:1.

Gearbox Selection for AGV Drives

For AGV drive systems, the gearbox ratio is selected to place the motor’s operating speed in its efficiency sweet spot (typically 1,500–3,000 RPM for BLDC motors). 以下 1,000 转速, torque ripple and cogging become noticeable; 多于 3,500 转速, bearing life degrades and noise increases [12].

我们的 spur vs. planetary gearbox comparison provides a detailed analysis of why planetary gearboxes are preferred for AGV applications — higher torque density, 较低的间隙, and coaxial output that simplifies wheel-hub integration. For applications requiring right-angle output (例如, steering drives), 我们的 变速箱产品页面 lists NMRV worm gearboxes and bevel-helical options.

Traction Verification: Preventing Wheel Slip

Calculating the required torque is necessary but not sufficient. The torque must be transmissible through the wheel-floor contact. If the applied torque exceeds the friction limit, the wheel slips — and encoder feedback becomes unreliable, directly affecting navigation accuracy [1].

Traction Limit Formula

Ftraction_max = μ × N驾驶

Where μ is the static friction coefficient between wheel and floor, and N驾驶 is the normal force on the driven wheel (not the total vehicle weight — only the weight borne by the driven wheels).

桌子 15. Static Friction Coefficients by Wheel/Floor Pair
Wheel MaterialFloor Material米 (static)笔记
Polyurethane (Shore 95A)Epoxy floor0.6Standard warehouse combination
PolyurethaneConcrete0.7Manufacturing floor
RubberEpoxy floor0.8Higher grip, faster floor wear
RubberConcrete0.9Maximum grip, 重型应用
NylonSteel rail0.3–0.4Rail-guided AGV; 低摩擦, requires high normal force

Verification rule: The per-wheel tractive force (Ftotal / n驾驶) must not exceed Ftraction_max. If it does, either increase the number of driven wheels, add ballast to increase normal force on driven wheels, or select a higher-friction tire compound.

For differential-drive AGVs, the in-place rotation condition is the most likely to cause slip because all the tractive force is concentrated on two wheels pivoting in place. If the calculated Fspin exceeds the traction limit, the AGV will scrub instead of rotating cleanly, causing tire wear and position error.

Reading Motor Datasheets: 麦克森, Faulhaber, and Yaskawa

Motor manufacturers present torque data in different formats. Understanding how to read these datasheets is essential for accurate AGV motor selection.

麦克森: Speed-Torque Line and Motor Constants

Maxon’s catalog specifies the speed-torque line, which is linear for coreless DC motors and BLDC motors with slotless windings. The key parameters are [11]:

  • Torque constant (k) in mNm/A — the proportional relationship between current and torque. For coreless Maxon motors, torque and current are strictly proportional, allowing the motor to function as a torque sensor by measuring current.
  • Speed-torque gradient (Δn/ΔM) in rpm/mNm — how much speed drops per unit of torque increase. A smaller value means a stiffer motor. The gradient is constant for most motors and equals the ratio of no-load speed to stall torque.
  • Nominal torque (maximum continuous torque) — the torque the motor can deliver indefinitely at 25°C ambient without exceeding its thermal class.
  • 堵转扭矩 — the torque at zero speed. Never an operating point; causes rapid overheating.

Maxon notes that motor constants have tolerances of up to ±10% and change with temperature. A warm motor is weaker — the speed-torque gradient increases as the motor heats up. This means a motor sized at the edge of its continuous torque rating at 25°C may be underpowered at 40°C ambient.

Faulhaber: Operating Range and Thermal Limits

Faulhaber’s DC Motors Technical Information [12] defines the motor’s operating range on the speed-torque diagram, bounded by:

  • Maximum continuous torque (thermal limit line) — the torque sustainable indefinitely.
  • Maximum speed (mechanical limit) — determined by bearing and commutation capabilities.
  • Maximum output power line — typically at 50% of stall torque and 50% of no-load speed.

Faulhaber recommends operating the motor such that the required speed is higher than half the no-load speed at nominal voltage, and the load torque is less than the maximum continuous torque. This ensures the motor operates in its efficient range and avoids excessive copper losses.

安川: SigmaSelect Sizing Methodology

Yaskawa’s SigmaSelect software [13] takes a system-level approach to servo motor selection. The user inputs:

  • Application load data (mass, 摩擦, external forces)
  • Mechanical transmission parameters (变速箱速比, 效率, 惯性)
  • Motion profile (速度, 加速度, dwell time)

The software then generates a report comparing the servo system’s capability (峰值扭矩, continuous torque, 速度, thermal capacity) against the application’s requirements (RMS torque, 峰值扭矩, maximum speed). This report format is valuable because it explicitly separates peak and continuous operating points and includes a thermal margin calculation. While Yaskawa’s SigmaSelect is designed for AC servo motors, the methodology applies directly to BLDC servo systems used in AGVs.

Seven Common Torque Sizing Mistakes

桌子 16. Common AGV Torque Sizing Errors and Corrections
#MistakeConsequenceCorrect Approach
1Using nominal wheel diameter instead of loaded radiusTorque underestimated by 5–10%Subtract tire compression (2–5 mm for PU) from nominal radius
2Ignoring slope torque because ramps are “短的”AGV stalls on ramp; motor overcurrent tripAlways include Fgrade in worst-case calculation, even for 3% grades
3Sizing by peak torque onlyMotor overheats during sustained operationCalculate TRMS over the duty cycle; verify against continuous rating
4Treating all drive wheels as equal traction contributorsInner wheel in turns gets less normal force, 纸条Account for load transfer during turning; verify traction per wheel
5Missing gearbox efficiency in motor-side torqueMotor undersized by 10–18% (1–2 stage planetary)Always divide wheel torque by (i × η), not just i
6Using catalog torque at 25°C without thermal deratingMotor trips on thermal protection at 40°C ambientApply derating factor per Table 11; specify insulation class
7Not verifying traction limitWheel slip, encoder feedback loss, navigation errorCompare per-wheel tractive force against μ × N驾驶

6-Step Torque Selection Workflow

The following workflow consolidates the methodology from this guide into a practical sequence for AGV motor selection. It is compatible with the approaches used by Oriental Motor’s AGV sizing tool [3], iNetic Motion’s calculator [4], and Yaskawa’s SigmaSelect [13].

桌子 17. 6-Step AGV Motor Torque Selection Workflow
ActionInput输出Common Error
1Define vehicle parametersGross mass, 目标速度, 加速度, max slope, 轮径, # driven wheelsLocked input set for calculationUsing brochure payload instead of gross mass (机壳 + 电池 + 有效负载)
2Calculate resistance forcesCrr, slope angle, 加速度, mass, 克Froll, Facc, Fgrade, FtotalUsing wrong Crr for the actual wheel/floor combination
3Compute wheel and motor torqueFtotal, r车轮, n驾驶, 安全系数, 变速箱速比, 或者时间车轮, 时间马达 (continuous)Forgetting safety factor or gearbox efficiency
4Select motor type and frame size时间马达, 目标速度, voltage platformMotor model, 框架尺寸, 电压, 额定功率Selecting by peak torque; ignoring continuous thermal rating
5Thermal validationDuty cycle profile, 环境温度, insulation class时间RMS, derated continuous torque, thermal marginNot applying ambient derating; using S1 rating for S4 duty
6Traction and inertia verification米, 否驾驶, Ĵ加载, Ĵ马达, 变速箱速比Slip margin, inertia ratio, control stability assessmentNot checking in-place rotation traction (highest slip risk)

For AGV applications requiring precise positioning (对接, pallet handling), also evaluate the servo motor vs. 步进电机 tradeoff, and consider the direct drive vs. 齿轮马达 comparison for hub-drive configurations. 我们的 BLDC 与. servo motors for AGVs analysis provides a three-layer comparison (标准无刷直流电机, 无刷直流伺服, 交流伺服) specific to AGV drive systems.

常问问题

How much torque does a typical AGV need?

It depends on payload. 一个 150 kg AMR needs approximately 0.4–0.7 N·m continuous motor torque per wheel (与一个 20:1 变速箱). 一个 1,200 kg AGV needs 3–5 N·m. A 5-ton transfer cart needs 10–15 N·m. The quick-reference table in Section 2 provides values for five payload classes.

What is the formula for AGV motor torque?

时间马达 = (Ftotal × r车轮 × SF) / (n驾驶 × i × η), where Ftotal = Froll + Facc + Fgrade, SF is the safety factor, i is the gearbox ratio, and η is the gearbox efficiency.

What safety factor should I use for AGV torque?

1.25–1.5 for indoor AMRs on smooth floors. 1.5–2.0 for industrial AGVs with ramps or frequent starts. 2.5 for safety-critical applications (医疗的, 食品加工, molten metal transport). The safety factor covers measurement uncertainty, friction variation, and degradation over the motor’s service life.

How does slope angle affect AGV torque?

Grade resistance is Fgrade = m × g × sin(我). 一个 3% ramp (1.72°) adds 294 N per 1,000 kg of mass. 对于一个 1,200 kg AGV, the grade force on a 3% ramp equals 353 N — nearly matching the rolling resistance. Always size for the worst-case slope in the operating environment.

Should I size for peak or continuous torque?

Both. The continuous torque must exceed the RMS torque of the duty cycle (thermal validation). The peak torque must exceed the worst-case transient (acceleration from standstill, ramp start, in-place rotation). Peak torque is typically 2–3× continuous for BLDC motors, available for 30–60 seconds.

What IEC standard applies to AGV motor torque?

国际电工委员会 60034-1:2022 defines duty cycle classifications (S1–S10). Most AGVs operate under S3 (intermittent periodic) or S4 (intermittent with starting influence). The motor’s rated torque must exceed the RMS torque at the operating ambient temperature, accounting for thermal derating per IEC 60034-1 thermal class limits.

下一步

If you have your AGV parameters ready — gross mass, 目标速度, 加速度, 坡, wheel diameter — our engineering team can run the torque calculation and recommend a motor, 变速箱, and controller combination. Contact GreenSky Power with your specifications, or browse our complete motor product catalog for BLDC motors, 行星齿轮箱, 和 电机控制器 suitable for AGV drive systems.

All GreenSky Power motors are tested per 国际电工委员会 60034 和国标 1032 检测标准, with dynamometer test reports included with every shipment. For AGV-specific applications, 我们提供 custom motor design with integrated encoder, 制动, and gearbox options.

参考

  1. Honest Edrive Equipment Co., 有限公司. (2026). 扭矩, 牵引力, and Tread: Engineering Factors in AGV Drive Wheels. 从 https 检索://www.hagvwheel.com/engineering-factors-in-agv-drive-wheels.html
  2. AGV Drive Wheel. (2026). How to Calculate AGV Drive Wheel Torque and Motor Sizing. 从 https 检索://agvdrivewheel.com/blog/how-to-calculate-agv-drive-wheel-torque-and-motor-sizing
  3. 东方汽车. (2026). AGV — Automatic Guided Vehicle Sizing Tool. 从 https 检索://www.orientalmotor.com/motor-sizing/agv-sizing.html
  4. iNetic Motion. (2026). 自动导引车 & AMR Motor Calculator for Robotics and Mobility. 从 https 检索://ineticmotion.com/agv-motor-calculator/
  5. Yikong Intelligent Equipment (Bicontrols). (2026). Differential Drive Wheel AGV Motor Sizing Guide: Torque Calculation and Inertia Matching. 从 https 检索://en.bicontrols.com/news_detail/104.html
  6. Yikong Intelligent Equipment (Bicontrols). (2025). AGV驱动电机的扭矩计算与优化: Enabling Flexible Logistics in Automotive Manufacturing. 从 https 检索://en.bicontrols.com/news_detail/50.html
  7. 国际电工委员会. (2026). 国际电工委员会 60034-1:2022 — Rotating Electrical Machines — Part 1: Rating and Performance. 版 15. Geneva: 国际电工委员会. 检索自 https://www.iec.ch/government-regulators/electric-motors
  8. Engineering ToolBox. (2026). Electric Motors — IEC and NEMA Standard Torques. 从 https 检索://www.engineeringtoolbox.com/iec-nema-standards-torques-d_741.html
  9. Siddiqui, F. A., et al. (2022). “Motor Parametric Calculations for Robot Locomotion.Engineering Proceedings, 20(1), 8. MDPI. 从 https 检索://www.mdpi.com/2673-4591/20/1/8
  10. DFRobot. (2025). How to Calculate the Motor Torque for a Mobile Robot. 从 https 检索://wiki.dfrobot.com/tutorial/20135
  11. 麦克森集团. (2025). Motor Data and Simulation — maxon Support. Standard Specification 100 (直流电机) / 101 (EC Motor). 从 https 检索://support.maxongroup.com/hc/en-us/articles/360013761160-Motor-data-and-simulation
  12. 博士. Fritz Faulhaber GmbH & 钴. 千克. (2022). Technical Information: 直流电机. 从 https 检索://www.faulhaber.com/fileadmin/Import/Media/EN_TECHNICAL_INFORMATION.pdf
  13. 安川美国, 公司. (2025). SigmaSelect Servo Sizing Software — Product Overview. 从 https 检索://www.yaskawa.com/products/motion/sigma-7-servo-products/software-tools/sigmaselect
  14. University of Florida, Machine Design Lab. (2015). Useful Motor/Torque Equations for EML2322L. 从 https 检索://web.mae.ufl.edu/designlab/motors/Useful%20Equations.pdf
  15. AGV Motor. (2025). AGV/AMR Design Calculator: Key Points from Parameter Calculations to Selection Guidelines. 从 https 检索://agvmotor.com/blogs/knowledge/agv-amr-design-calculator-key-points-from-parameter-calculations-to-selection-guidelines

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