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PR2 Gripper Transmission

Basic transmission equations:

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Where

Jacobians

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where

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Inverse Transform (from $$\theta$$ to $$MR$$)

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where
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and
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Transmissions

Denote

Propagate From Actuator State to Joint State $$(P_a,V_a,E_a) \rarr (P_j,V_j,E_j)$$

Motor angle in radians ($$P_a$$) is converted to motor revolutions ($$MR$$),

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and we have the transmission equation for gripper gap size above

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.

Motor angular rates in radians per second (

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) is converted to revolutions per second,

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and the gripper gap velocity is approximated by

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Given motor torque

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, gripper effort
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is approximated by

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where

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is the moment of inertia at the motor and
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is defined as
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is the motor torque in
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.

Propagate From Joint State to Actuator State $$(P_j,V_j,E_j) \rarr (P_a,V_a,E_a)$$

pretty much the reverse of previous section, given

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, inverse transmission gives
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, and

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.

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Known Limitations


2022-05-28 12:53