Dog Clutch

Clutch with toothed plates that engage when plate teeth become enmeshed

Libraries:
Simscape / Driveline / Clutches

Description

The Dog Clutch block represents a nonslip clutch that uses the positive engagement of interlocking teeth to transfer torque between drive shafts. Dog clutches are common in applications that require high-speed and frequent gear shifts. Dog clutches are typical for motorcycle manual transmissions, and some industrial machinery.

The ring and hub are the primary components of a dog clutch. The input shaft turns the ring, which has slots or teeth. The hub connects to an output shaft that has protruding "dogs" that fit into the slots of the ring. When you shift the transmission,the dogs and slots engage and lock the two components and transmitting power. You shift again to disengage the clutch, which causes the dogs to disengage from the slots and allows the transmission to spin freely. The ring and the hub spin together as a unit.

To control engagement, the dog clutch contains a shift linkage that governs the position of the ring with respect to the hub. You can choose to control the shift linkage with a physical signal or a mechanical translational conserving port by using the Torque transmission model parameter. Choose the parameter setting according to your performance, fidelity, and the clutch behavior:

Two-mode — Fully abstracted torque transmission model based on mode charts. This setting is fast enough for real-time simulation and does not require knowledge of the clutch dimensions. You can control the shift linkage only with a physical or logic-controlled signal.
Friction clutch approximation - Suitable for HIL and linearization — Medium- to high-fidelity composite implementation of the Fundamental Friction Clutch block. This setting supports thermal modeling. You can control the shift linkage with either a physical signal or a mechanical translational conserving port.
Dynamic with backlash — High-fidelity clutch engagement model that accounts for phenomena such as backlash, torsional compliance, and contact forces between the ring and hub teeth.
Dynamic modal — Medium to high-fidelity mode chart implementation that simulates engagement blocking and determines the shift linkage position from a mechanical translational conserving port.

Moving the ring toward the hub so that the teeth interlock changes the clutch state to engaged. Tooth overlap must exceed a minimum value for engagement. Moving the ring in reverse so that the two sets of teeth no longer interlock changes the clutch state back to disengaged. Port S specifies the shift linkage position. When the clutch is fully disengaged, the shift linkage position is zero. When the clutch is fully engaged, the shift linkage position equals the sum of the tooth height and the ring-hub clearance of the fully disengaged state,

$z = h + z_{G a p},$

where:

z is the shift linkage position.
h is the tooth height.
z_Gap is the ring hub clearance when disengaged.

The figure shows side and front views of the dog clutch and some of its relevant variables.

Torque Transmission Models

You can choose from these torque transmission models.

Two-Mode

To simulate an abstracted dog clutch, set Torque transmission model to Two-mode. The two-mode torque transmission model uses mode charts to control whether the clutch is engaged or disengaged. You can control the shift linkage position using logic-based commands or a linkage position physical signal. When you use logic-based commands, false at port X represents a disengaged clutch, and true represents an engaged clutch.

Friction Clutch Approximate Model

When you set Torque transmission model to Friction clutch approximation - Suitable for HIL and, the block treats the clutch engagement as a friction phenomenon between the ring and the hub. This setting is better suited for linearization, fixed-step simulation, and hardware-in-loop (HIL) simulation. The block uses a composite implementation of the Fundamental Friction Clutch block.

When you use this setting, the clutch has three possible configurations: disengaged, engaged, and locked. When disengaged, the contact force between the ring and the hub is zero. This force remains zero until the shift linkage reaches the minimum position for engagement.

When the ring-hub tooth overlap, h, exceeds the minimum value for engagement, the contact force between the two components begins to increase linearly with the shift linkage position, z.

At full engagement, the contact force reaches its maximum value and the clutch state switches to locked. In this state, the ring and the hub spin as a unit without slip. To unlock the clutch, the transmitted torque must exceed the value of the Maximum transmitted torque parameter.

Dynamic with Backlash

When you set Torque transmission model to Dynamic with backlash, the block simulates clutch phenomena such as backlash, torsional compliance, and contact forces between ring and hub teeth. This model provides greater accuracy than the friction clutch approximation.

When you use this setting, the clutch has two possible configurations: disengaged and engaged. When disengaged, the contact force between the ring and the hub is zero. This force remains zero until the shift linkage reaches the minimum position for engagement.

When the ring-hub tooth overlap, h, exceeds the engagement threshold value, the clutch transmits torque. This torque is the sum of torsional spring and damper components, including backlash between the ring and hub teeth, such that $T_{C} = {\begin{matrix} - k_{R H} (ϕ - \frac{δ}{2}) - μ_{R} \cdot ω & ϕ > \frac{δ}{2} \\ 0 & - \frac{δ}{2} < ϕ < \frac{δ}{2} \\ - k_{R H} (ϕ + \frac{δ}{2}) - μ_{R} ω & ϕ < - \frac{δ}{2} \end{matrix},$ where:

k_RH is the torsional stiffness of the ring-hub coupling.
ϕ is the relative angle, about the common rotation axis, between the ring and the hub.
δ is the backlash between ring and hub teeth.
ω is the relative angular velocity between the ring and the hub. This variable describes how fast the two components slip past each other.

Compliant end stops limit the translational motion of the clutch shift linkage and the ring. The compliance model treats the end stops as linear spring-damper sets. The location of the end stops depends on the relative angle and angular velocity between the ring and hub teeth:

If the teeth align and the relative angular velocity is smaller than the maximum value for clutch engagement, the end stop location is the sum of the ring-hub clearance when fully disengaged and the tooth height. The clutch can engage in this end stop position.
If the teeth do not align or the relative angular velocity exceeds the maximum value for clutch engagement, the end-stop location is set to prevent the ring from engaging the hub. The clutch does not engage in this end stop position.

Translational friction opposes shift linkage and ring motion. This friction is the sum of Coulomb and viscous components, such that $F_{Z} = - k_{K} \cdot F_{N} \cdot \tanh (\frac{4 v}{v_{t h}}) - μ_{T} v,$ where:

F_Z is the net translational friction force acting on the shift linkage and ring.
k_K is the kinetic friction coefficient between ring and hub teeth.
F_N is the normal force between ring and hub teeth, where F_N = T_C/R_m.
v is the translational velocity of the shift linkage and the ring.
v_th is the translational velocity threshold. Below this threshold, a hyperbolic tangent function smooths the Coulomb friction force to zero as the shift linkage and ring velocity tends to zero.
μ_T is the viscous damping coefficient acting on the shift linkage and the ring.

Dynamic Modal

When you set Torque transmission model to Dynamic modal, the block determines the discrete clutch modal behavior by taking the shift linkage position from the mechanical translational conserving port S. This setting captures more complex clutch dynamics than the Two-mode parameterization and is faster than the Friction clutch approximation and Dynamic with backlash settings.

You can use the Dynamic modal setting to simulate engagement blocking when the speed difference is too large for the clutch plates to engage. The block represents engagement blocking as a spring-damper system where you can parameterize the spring and damping coefficients. The engagement modes overlap, which prevents the mode from changing until the shift linkage position is beyond the engagement overlap region. You define the engagement overlap region using the Tooth overlap to engage parameter.

Diagram depicting the mode transitions between engaged and disengage. The z variable represents the shift linkage position. The Engaged and Disengaged modal regions overlap, which attenuates the mode transition rate.

The linkage position constrains are:

z is the shift linkage position at port S.
h is the Tooth height parameter.
z_Gap is the Ring hub clearance when disengaged parameter.
z_Overlap is the Tooth overlap to engage parameter.
ω_thr is the Engagement speed threshold parameter.

The engagement mode positions are:

z = 0 — The clutch is fully disengaged.
0 < z < z_Gap — The clutch is disengaged when the shift linkage position is in the region defined by z_Gap. The clutch can transition from disengaged to engaged at x = z_Gap + z_Overlap.
z_Gap < z < h — The clutch is engaged when z is in the region defined by h. The clutch can transition from engaged to disengaged when z = z_Gap.
z = z_Gap + h — The clutch is fully engaged.
z = z_Gap + z_Overlap — When z is in the engagement overlap region, the clutch engages only when the speed difference is less than the value of the ω_thr parameter.

Rotational Power Dissipation

When the clutch slips under an applied torque, it dissipates power. The power loss equals the product of the slip angular velocity and the contact torque between the ring and the hub, such that

$P_{l o s s} = ω \cdot T_{C},$

where:

P_loss is the dissipated power due to slipping.
T_C is the kinetic contact torque.

Thermal Modeling

When you set Torque transmission model to Friction clutch approximation - Suitable for HIL and linearization, you can model the effects of heat flow and temperature change by using the optional thermal conserving port, T.

Linearization

To optimize your model for linearization, use the Clutch > Torque transmission model parameter default setting, Friction clutch approximation - Suitable for HIL and linearization.

Hardware-in-the-Loop Simulation

For optimal simulation performance, use the Clutch > Torque transmission model parameter default setting, Friction clutch approximation - Suitable for HIL and linearization.

Examples

Dog Clutch with Dynamic Modal Model

The engage and disengage behavior of a dog clutch using the dynamic modal model for torque transmission. The block parameterization uses mode charts to control the clutch engagement. The clutch fails to engage when the speed difference between the ring and hub is too great.

Open Model

Vehicle with Dual Clutch Transmission

A vehicle with a five-speed dual-clutch transmission. Gear shifts are implemented via the two clutches, one clutch pressure being ramped up as the other clutch pressure is ramped down. Gear pre-selection via dog clutches ensures that the correct gear is fully selected before the on-going clutch is enabled.

Open Model

Ports

Input

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S — Logical shift linkage, unitless
physical signal

Physical signal input port associated with the shift linkage, unitless. A logical true allows the clutch to engage if the relative speeds of the hub and ring are within tolerance. A logical false causes the clutch to disengage.

Dependencies

To enable this port, set Torque transmission model to:

Two-mode
Friction clutch approximation - Suitable for HIL and linearization, and set Shift linkage control to Physical signal
Dynamic with backlash, and set Shift linkage control to Physical signal

Output

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X — Clutch position, m or unitless
physical signal

Physical signal output port associated with the clutch position, in m or unitless. When you set Torque transmission model to Two-mode, the port outputs a logical value true for engaged or false for disengaged. Otherwise, the port outputs the position of the clutch.

Conserving

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H — Clutch hub
mechanical rotational

Mechanical rotational conserving port associated with the clutch hub

R — Clutch ring
mechanical rotational

Mechanical rotational conserving port associated with the clutch ring.

S — Shift linkage
mechanical translational

Mechanical translational conserving port associated with shift linkage.

Dependencies

To enable this port, set Torque transmission model to:

Friction clutch approximation - Suitable for HIL and linearization
Dynamic modal
Dynamic with backlash and set Shift linkage control to Conserving port

T — Heat flow
thermal

Thermal conserving port associated with heat flow.

Dependencies

To enable this port, set Torque transmission model to Friction clutch approximation - Suitable for HIL and linearization, and set Thermal port to Model.

Parameters

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Clutch

Torque transmission model — Torque transmission model
`Two-mode` (default) | `Friction clutch approximation - Suitable for HIL and linearization` | `Dynamic with backlash` | `Dynamic modal`

Method to model the behavior of the dog clutch:

Two-mode — Fully abstracted torque transmission model based on mode charts. This setting is fast enough for real time simulation and does not require knowledge of the clutch dimensions. You can control the shift linkage only with a physical or logic-controlled signal.
Friction clutch approximation - Suitable for HIL and linearization — Medium- to high-fidelity composite implementation of the Fundamental Friction Clutch block. This setting supports thermal modeling. You can control the shift linkage by using either a physical signal or a mechanical translational conserving connection.
Dynamic with backlash — High-fidelity clutch engagement model, that accounts for phenomena such as backlash, torsional compliance, and contact forces between the ring and hub teeth.
Dynamic modal — System-level clutch engagement model that captures the effects of engagement blocking due to the speed differential.

Engagement speed threshold — Engagement speed threshold
`5` `rpm` (default) | positive scalar

Minimum rotational speed at which the clutch delivers power.

Dependencies

To enable this parameter, set Torque transmission model to Two-mode or Dynamic modal.

Thermal port — Option to enable thermal port
`Omit` (default) | `Model`

Whether to enable the thermal conserving port, T.

Dependencies

To enable this parameter, set Torque transmission model to Friction clutch approximation - Suitable for HIL and linearization.

Clutch teeth mean radius — Clutch teeth mean radius
`50` `mm` (default) | positive scalar

Distance from the ring or hub center to the corresponding tooth center. The mean tooth radius determines the normal contact forces between the ring and hub teeth given the transmission torque between the two components. The value must be greater than zero.

Dependencies

To enable this parameter, set Torque transmission model to Friction clutch approximation - Suitable for HIL and linearization or Dynamic with backlash.

Maximum transmitted torque — Maximum transmitted torque
`1000` `N*m` (default) | positive scalar

Largest torque that the clutch can transmit. This value corresponds to a nonslip engaged configuration. If the torque transmitted between the ring and the hub exceeds this value, the two components begin to slip with respect to each other. This torque determines the static friction limit in the friction clutch approximation.

Dependencies

To enable this parameter, set Torque transmission model to Friction clutch approximation - Suitable for HIL and linearization, and set Thermal port to Omit.

Temperature vector — Temperature
`[280, 300, 320]` `K` (default) | vector

Temperature values. The minimum number of values depends on the interpolation method that you select. For linear interpolation, provide at least two values per dimension. For smooth interpolation, provide at least three values per dimension. The values in the vector must increase from left to right.

Dependencies

To enable this parameter, set Torque transmission model to Friction clutch approximation - Suitable for HIL and linearization, and set Thermal port to Model.

Maximum transmitted torque vector — Maximum transmitted torque
`[1000, 1050, 1000]` `N*m` (default) | vector

Maximum transmitted torque for a given temperature in the Temperature vector parameter.

Dependencies

To enable this parameter, set Torque transmission model to Friction clutch approximation - Suitable for HIL and linearization, and set Thermal port to Model.

Interpolation method — Interpolation method
`Linear` (default) | `Smooth`

Interpolation method for approximating the output value when the input value is between two consecutive grid points:

Linear — Select this option for the best performance.
Smooth — Select this option to produce a continuous curve with continuous first-order derivatives.

For more information on interpolation algorithms, see the PS Lookup Table (1D) block reference page.

Dependencies

To enable this parameter, set Torque transmission model to Friction clutch approximation - Suitable for HIL and linearization, and set Thermal port to Model.

Extrapolation method — Extrapolation method
`Linear` (default) | `Nearest` | `Error`

Extrapolation method for determining the output value when the input value is outside the range specified in the argument list:

Linear — Select this option to produce a curve with continuous first-order derivatives in the extrapolation region and at the boundary with the interpolation region.
Nearest — Select this option to produce an extrapolation that does not go above the highest point in the data or below the lowest point in the data.
Error — Select this option to avoid going into the extrapolation mode. If the input signal is outside the range of the table, the simulation stops and generates an error.

For more information on extrapolation algorithms, see the PS Lookup Table (1D) block reference page.

Dependencies

To enable this parameter, set Torque transmission model to Friction clutch approximation - Suitable for HIL and linearization, and set Thermal port to Model.

Number of teeth — Number of ring or hub teeth
`6` (default) | positive nonzero scalar integer

Total number of teeth in the ring or the hub. The two components have equal tooth numbers. The value must be greater than or equal to one.

Dependencies

To enable this parameter, set Torque transmission model to Dynamic with backlash.

Rotational backlash — Rotational backlash
`10` `deg` (default) | positive scalar

Allowable angular motion, or play, between the ring and hub teeth when the clutch is engaged. The value must be greater than zero.

Dependencies

To enable this parameter, set Torque transmission model to Dynamic with backlash.

Torsional stiffness — Torsional stiffness
`10e6` `N*m/rad` (default) | positive scalar

Linear torsional stiffness coefficient at the contact interface between the ring and hub teeth. This coefficient characterizes the restoring component of the contact force between the two sets of teeth. Greater stiffness values correspond to greater contact forces. The value must be greater than zero.

Dependencies

To enable this parameter, set Torque transmission model to Dynamic with backlash.

Torsional damping — Torsional damping
`100` `Nms/rad` (default) | positive scalar

Linear torsional damping coefficient at the contact interface between the ring and hub teeth. This coefficient characterizes the dissipative component of the contact force between the two sets of teeth. Greater damping values correspond to greater energy dissipation during contact. The value must be greater than zero.

Dependencies

To enable this parameter, set Torque transmission model to Dynamic with backlash.

Shift Linkage

Abstract shift linkage control — Two-mode linkage control option
`Logic-controlled` (default) | `Physical signal`

Abstract shift linkage control to use for two-mode torque transmission.

Logic-controlled — Input the shift linkage as a Boolean operator using the physical signal port S.
Physical signal — Input shift linkage position directly through the physical signal port S.

Dependencies

To enable this parameter, set Torque transmission model to Two-mode.

Shift linkage control — Shift linkage control port
`Physical signal` (default) | `Conserving port`

Port type for shift linkage control:

Physical signal — Input shift linkage position directly through the physical signal port, S.
Conserving port — Input the shift linkage position dynamically through the translational conserving port, S.

Dependencies

To enable this parameter, set Torque transmission model to Friction clutch approximation - Suitable for HIL and linearization or Dynamic with backlash.

Tooth height — Tooth height
`10` `mm` (default) | positive scalar

Distance between the base and crest of a tooth. The ring and hub teeth share the same height. The tooth height and the ring-hub clearance when fully disengaged determine the maximum travel span of the shift linkage. The value of this parameter must be greater than zero.

Dependencies

To enable this parameter, set Torque transmission model to:

Friction clutch approximation - Suitable for HIL and linearization
Dynamic with backlash
Dynamic modal
Two-mode, and set Abstract shift linkage control to Physical signal

Ring-hub clearance when disengaged — Ring-hub clearance when disengaged
`3` `mm` (default) | positive scalar

Maximum open gap between the ring and hub tooth crests along the shift linkage translation axis. This gap corresponds to the fully disengaged clutch state. The tooth height and the ring-hub clearance when fully disengaged determine the maximum travel span of the shift linkage. The value of this parameter must be greater than zero.

Dependencies

To enable this parameter, set Torque transmission model to:

Friction clutch approximation - Suitable for HIL and linearization
Dynamic with backlash
Dynamic modal
Two-mode, and set Abstract shift linkage control to Physical signal

Hard stop at back of shift linkage — Hard stop backing option
`on` (default) | `off`

Whether to enable a hard stop when the shift linkage travels beyond the fully disengaged position.

Dependencies

To enable this parameter, set Torque transmission model to:

Dynamic modal
Friction clutch approximation - Suitable for HIL and linearization, and set Shift linkage control to Conserving port
Dynamic with backlash and set Shift linkage control to Conserving port

Ring stop stiffness — Ring stop stiffness
`10e5` `N/m` (default) | positive scalar

Linear stiffness coefficient of the ring end stop. This coefficient characterizes the restoring component of the contact force that resists translational motion past the end stops. Greater stiffness values correspond to greater contact forces and a smaller end stop compliance. The value must be greater than zero.

Dependencies

To enable this parameter, set Torque transmission model to Friction clutch approximation - Suitable for HIL and linearization or Dynamic with backlash and set Shift linkage control to Conserving port.

Ring stop damping — Ring stop damping
`1e3` `N*s/m` (default) | nonegative scalar

Linear damping coefficient of the ring end stop. This coefficient characterizes the dissipative component of the contact force that resists translational motion past the end stops. Greater damping values correspond to greater energy dissipation during contact. The value must be greater than or equal to zero

Dependencies

Shift linkage viscous friction coefficient — Shift linkage viscous friction coefficient
`100` `N*s/m` (default) | positive scalar

Linear damping coefficient acting on the shift linkage. This coefficient characterizes the dissipative force that resists shift linkage motion due to viscous damping. Greater coefficient values correspond to greater energy dissipation during shift linkage motion. The value must be greater than zero.

Dependencies

Tooth-tooth friction coefficient — Tooth-tooth contact kinetic friction coefficient
`0.05` (default) | positive scalar

Kinetic friction coefficient at the contact interface between the ring and hub teeth. This coefficient characterizes the dissipative force that resists shift linkage motion due to tooth-to-tooth contact during clutch engagement and disengagement.

Greater coefficient values correspond to greater energy dissipation during shift linkage motion. The value must be greater than zero.

Dependencies

To enable this parameter, set:

Torque transmission model to Dynamic with backlash
Shift linkage control to Conserving port

Shift linkage engaged friction coefficient — Engaged friction coefficient
`100` `N*s/m` (default) | positive scalar

Friction coefficient at the shift linkage when the ring and hub are engaged. This value is the friction between the shift linkage and its support.

Dependencies

To enable this parameter, set Torque transmission model to Dynamic modal.

Shift linkage disengaged friction coefficient — Disengaged friction coefficient
`50` `N*s/m` (default) | positive scalar

Friction coefficient at the shift linkage when the ring and hub are disengaged. This value is the friction between the shift linkage and its support.

Dependencies

To enable this parameter, set Torque transmission model to Dynamic modal.

Static contact speed threshold — Static contact speed threshold
`0.1` `m/s` (default) | positive scalar

Dependencies

To enable this parameter, set Torque transmission model to Dynamic modal.

Static contact release force threshold — Release force threshold
`0.001` `N` (default) | positive scalar

Force threshold above which the ring and hub can unlock and disengage.

Dependencies

To enable this parameter, set Torque transmission model to Dynamic modal.

Engagement Conditions

Linkage travel direction — Engagement condition travel direction
`Positive shift linkage displacement engages clutch` (default) | `Negative shift linkage displacement engages clutch`

Direction the shift linkage must travel in to engage the clutch.

Dependencies

To enable this parameter, set Torque transmission model to:

Friction clutch approximation - Suitable for HIL and linearization
Dynamic with backlash
Dynamic modal

Maximum engagement speed — Engagement speed upper velocity threshold
`inf` (default) | positive scalar

Relative angular velocity between the ring and the hub above which the clutch cannot engage. The value is specific to the specific gearbox or transmission. Minimizing the value helps avoid high dynamic impact during engagement. The value must be greater than zero.

Dependencies

To enable this parameter, set Torque transmission model to Friction clutch approximation - Suitable for HIL and linearization or Dynamic with backlash.

Tooth overlap to engage — Tooth overlap engagement threshold
`3` `mm` (default) | positive scalar

Overlap length between the ring and hub teeth along the common longitudinal axis. The clutch engages when the tooth overlap is greater than this value. The clutch remains disengaged until the meshing gear teeth overlap by at least this length. The value must be greater than zero.

Dependencies

To enable this parameter, set Torque transmission model to

Dynamic modal
Friction clutch approximation - Suitable for HIL and linearization, and set Shift linkage control to Conserving port
Dynamic with backlash and set Shift linkage control to Conserving port

Engagement block stiffness — Engagement blocking stiffness coefficient
`10e6` `N/m` (default) | positive scalar

Stiffness coefficient during engagement blocking.

Dependencies

To enable this parameter, set Torque transmission model to Dynamic modal.

Engagement block damping — Engagement blocking damping coefficient
`300` `N*s/m` (default) | positive scalar

Damping coefficient when during engagement blocking.

Dependencies

To enable this parameter, set Torque transmission model to Dynamic modal.

Initial Conditions

Clutch locked — Initial clutch state
`off` (default) | `on`

Clutch state at the start of simulation:

off — Clutch transmits zero torque between the ring and the hub.
on — Clutch transmits torque between the ring and the hub.

Initial shift linkage position — Initial shift linkage position
`0` `mm` (default) | scalar

Shift linkage position at simulation time zero. The clutch is disengaged when this value is between zero and the sum of the ring-hub clearance.

Dependencies

To enable this parameter, set:

Torque transmission model to Dynamic with backlash
Thermal model to Omit
Shift linkage control to Conserving port

Initial ring-hub offset angle — Initial ring-hub offset angle
`0` `deg` (default) | scalar

Rotation angle between the ring and the hub at simulation time zero. This angle determines whether the ring and hub teeth can engage. The initial offset angle must satisfy these conditions:

If the clutch initial state is disengaged, the initial offset angle must fall in the range

$- \frac{180^{°}}{N} \leq ϕ_{0} \leq + \frac{180^{°}}{N},$
where N is the number of teeth present in the ring or the hub. The two components contain the same number of teeth.
If the clutch initial state is engaged, the initial offset angle must fall in the range

$- \frac{δ}{2} \leq ϕ_{0} \leq + \frac{δ}{2},$
where δ is the backlash angle between the ring and hub teeth.

Dependencies

To enable this parameter, set Torque transmission model to Dynamic with backlash, and set Thermal port to Omit.

Thermal Port

Thermal mass — Resistance to temperature change
`50` `kJ/K` (default) | scalar

Thermal energy required to change the component temperature by a single degree. The greater the thermal mass, the more resistant the component is to temperature change.

Dependencies

To enable this parameter, set Torque transmission model to Friction clutch approximation - Suitable for HIL and linearization, and set Thermal port to Model.

Initial temperature — Initial temperature
`300` `K` (default) | scalar

Component temperature at the start of simulation. The initial temperature alters the component efficiency by adjusting the starting meshing or friction losses.

Dependencies

To enable this parameter, set Torque transmission model to Friction clutch approximation - Suitable for HIL and linearization, and set Thermal port to Model.

Extended Capabilities

C/C++ Code Generation
Generate C and C++ code using Simulink® Coder™.

Version History

Introduced in R2011a

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R2024a: Capture effects of engagement blocking due to speed differentials

You can now capture the effects of engagement blocking due to the speed differential at the system level when Torque transmission model is Dynamic modal.

R2023b: Two-mode support

The Dog Clutch block can now model abstract behavior when Torque transmission model is Two-mode. Use this option for system-level design or where speed is a priority over precision.

Dog Clutch

Description

Torque Transmission Models

Rotational Power Dissipation

Thermal Modeling

Linearization

Hardware-in-the-Loop Simulation

Examples

Dog Clutch with Dynamic Modal Model

Vehicle with Dual Clutch Transmission

Ports

Input

S — Logical shift linkage, unitless physical signal

Dependencies

Output

X — Clutch position, m or unitless physical signal

Conserving

H — Clutch hub mechanical rotational

R — Clutch ring mechanical rotational

S — Shift linkage mechanical translational

Dependencies

T — Heat flow thermal

Dependencies

Parameters

Clutch

Torque transmission model — Torque transmission model Two-mode (default) | Friction clutch approximation - Suitable for HIL and linearization | Dynamic with backlash | Dynamic modal

Engagement speed threshold — Engagement speed threshold 5 rpm (default) | positive scalar

Dependencies

Thermal port — Option to enable thermal port Omit (default) | Model

Dependencies

Clutch teeth mean radius — Clutch teeth mean radius 50 mm (default) | positive scalar

Dependencies

Maximum transmitted torque — Maximum transmitted torque 1000 N*m (default) | positive scalar

Dependencies

Temperature vector — Temperature [280, 300, 320] K (default) | vector

Dependencies

Maximum transmitted torque vector — Maximum transmitted torque [1000, 1050, 1000] N*m (default) | vector

Dependencies

Interpolation method — Interpolation method Linear (default) | Smooth

Dependencies

Extrapolation method — Extrapolation method Linear (default) | Nearest | Error

Dependencies

Number of teeth — Number of ring or hub teeth 6 (default) | positive nonzero scalar integer

Dependencies

Rotational backlash — Rotational backlash 10 deg (default) | positive scalar

Dependencies

Torsional stiffness — Torsional stiffness 10e6 N*m/rad (default) | positive scalar

Dependencies

Torsional damping — Torsional damping 100 N*m*s/rad (default) | positive scalar

Dependencies

Shift Linkage

Abstract shift linkage control — Two-mode linkage control option Logic-controlled (default) | Physical signal

Dependencies

Shift linkage control — Shift linkage control port Physical signal (default) | Conserving port

Dependencies

Tooth height — Tooth height 10 mm (default) | positive scalar

Dependencies

Ring-hub clearance when disengaged — Ring-hub clearance when disengaged 3 mm (default) | positive scalar

Dependencies

Hard stop at back of shift linkage — Hard stop backing option on (default) | off

Dependencies

Ring stop stiffness — Ring stop stiffness 10e5 N/m (default) | positive scalar

Dependencies

Ring stop damping — Ring stop damping 1e3 N*s/m (default) | nonegative scalar

Dependencies

Shift linkage viscous friction coefficient — Shift linkage viscous friction coefficient 100 N*s/m (default) | positive scalar

Dependencies

Tooth-tooth friction coefficient — Tooth-tooth contact kinetic friction coefficient 0.05 (default) | positive scalar

Dependencies

Shift linkage engaged friction coefficient — Engaged friction coefficient 100 N*s/m (default) | positive scalar

Dependencies

Shift linkage disengaged friction coefficient — Disengaged friction coefficient 50 N*s/m (default) | positive scalar

Dependencies

Static contact speed threshold — Static contact speed threshold 0.1 m/s (default) | positive scalar

Dependencies

Static contact release force threshold — Release force threshold 0.001 N (default) | positive scalar

Dependencies

Engagement Conditions

Linkage travel direction — Engagement condition travel direction Positive shift linkage displacement engages clutch (default) | Negative shift linkage displacement engages clutch

Dependencies

S — Logical shift linkage, unitless
physical signal

X — Clutch position, m or unitless
physical signal

H — Clutch hub
mechanical rotational

R — Clutch ring
mechanical rotational

S — Shift linkage
mechanical translational

T — Heat flow
thermal

Torque transmission model — Torque transmission model
`Two-mode` (default) | `Friction clutch approximation - Suitable for HIL and linearization` | `Dynamic with backlash` | `Dynamic modal`

Engagement speed threshold — Engagement speed threshold
`5` `rpm` (default) | positive scalar

Thermal port — Option to enable thermal port
`Omit` (default) | `Model`

Clutch teeth mean radius — Clutch teeth mean radius
`50` `mm` (default) | positive scalar

Maximum transmitted torque — Maximum transmitted torque
`1000` `N*m` (default) | positive scalar

Temperature vector — Temperature
`[280, 300, 320]` `K` (default) | vector

Maximum transmitted torque vector — Maximum transmitted torque
`[1000, 1050, 1000]` `N*m` (default) | vector

Interpolation method — Interpolation method
`Linear` (default) | `Smooth`

Extrapolation method — Extrapolation method
`Linear` (default) | `Nearest` | `Error`

Number of teeth — Number of ring or hub teeth
`6` (default) | positive nonzero scalar integer

Rotational backlash — Rotational backlash
`10` `deg` (default) | positive scalar

Torsional stiffness — Torsional stiffness
`10e6` `N*m/rad` (default) | positive scalar

Torsional damping — Torsional damping
`100` `Nms/rad` (default) | positive scalar

Abstract shift linkage control — Two-mode linkage control option
`Logic-controlled` (default) | `Physical signal`

Shift linkage control — Shift linkage control port
`Physical signal` (default) | `Conserving port`

Tooth height — Tooth height
`10` `mm` (default) | positive scalar

Ring-hub clearance when disengaged — Ring-hub clearance when disengaged
`3` `mm` (default) | positive scalar

Hard stop at back of shift linkage — Hard stop backing option
`on` (default) | `off`

Ring stop stiffness — Ring stop stiffness
`10e5` `N/m` (default) | positive scalar

Ring stop damping — Ring stop damping
`1e3` `N*s/m` (default) | nonegative scalar

Shift linkage viscous friction coefficient — Shift linkage viscous friction coefficient
`100` `N*s/m` (default) | positive scalar

Tooth-tooth friction coefficient — Tooth-tooth contact kinetic friction coefficient
`0.05` (default) | positive scalar

Shift linkage engaged friction coefficient — Engaged friction coefficient
`100` `N*s/m` (default) | positive scalar

Shift linkage disengaged friction coefficient — Disengaged friction coefficient
`50` `N*s/m` (default) | positive scalar

Static contact speed threshold — Static contact speed threshold
`0.1` `m/s` (default) | positive scalar

Static contact release force threshold — Release force threshold
`0.001` `N` (default) | positive scalar

Linkage travel direction — Engagement condition travel direction
`Positive shift linkage displacement engages clutch` (default) | `Negative shift linkage displacement engages clutch`

Maximum engagement speed — Engagement speed upper velocity threshold
`inf` (default) | positive scalar

Tooth overlap to engage — Tooth overlap engagement threshold
`3` `mm` (default) | positive scalar

Engagement block stiffness — Engagement blocking stiffness coefficient
`10e6` `N/m` (default) | positive scalar

Engagement block damping — Engagement blocking damping coefficient
`300` `N*s/m` (default) | positive scalar

Clutch locked — Initial clutch state
`off` (default) | `on`

Initial shift linkage position — Initial shift linkage position
`0` `mm` (default) | scalar

Initial ring-hub offset angle — Initial ring-hub offset angle
`0` `deg` (default) | scalar

Thermal mass — Resistance to temperature change
`50` `kJ/K` (default) | scalar

Initial temperature — Initial temperature
`300` `K` (default) | scalar

C/C++ Code Generation
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