Position Regulation with Feed Forward - Maxon Motor ag

maxon motor control
EPOS Application Note: Position Regulation with Feed Forward
EPOS Positioning Controller
Object dictionary entries
Units
Symbol Name Index Sub-Index
K P Position Regulator P-Gain 0x60FB 0x01
K I Position Regulator I-Gain 0x60FB 0x02
K D Position Regulator D-Gain 0x60FB 0x03
K ω Velocity Feedforward Factor 0x60FB 0x04
K α Acceleration Feedforward Factor 0x60FB 0x05
Acceleration:
Velocity:
Position: [ ]
Current: [ mA ]
K P :
K I :
K D :
K : α
K : α
K : ω
Operation Modes
⎡rad
⎤
⎢ 2
⎣ s ⎥ ⎦
⎡rad
⎤
⎢
⎣ s ⎥ ⎦
⎡ 1⋅
( turn)
⎤
qc = ⎢
⎥ (quadrature counts)
⎣ Encoder _ pulse _ number ⋅ 4⎦
⎡ mA ⎤
⎢ ⎥
⎣kSP
⋅ kS
⋅ qc ⎦
⎡ mA ⎤
⎢
⎥
⎣kSI
⋅ kS
⋅ qc ⋅TS
⎦
⎡ mA⋅T
⎤
S
⎢ ⎥
⎣kSD
⋅ kS
⋅ qc ⎦
⎡ A −6 ⎤
⎢
⋅10
2
⎣rad
/ s ⎥ ⎦
⎡ A −7 ⎤
⎢
⋅10
2
⎣rad
/ s ⎥ ⎦
⎡ µ A ⎤
⎢
⎣rad
/ s ⎥ ⎦
(EPOS 24/5, EPOS 70/10 and MCD EPOS 60W)
(EPOS 24/1)
(EPOS 24/1, EPOS 24/5, EPOS 70/10 and MCD EPOS 60W)
The acceleration and velocity feed forward take effect in Profile Position Mode and Homing Mode. There is no
influence to all the other operation modes like Position Mode, Profile Velocity Mode, Velocity Mode and Current
Mode.
Purpose of K (Acceleration Feedforward Factor)
α
K provides additional current in cases of high acceleration and/or high load inertias.
α
Purpose of K (Velocity Feedforward Factor)
ω
K provides additional current in cases, where the load increases with speed, e.g. speed dependent friction. The
ω
load is assumed to increase linear with speed.
Edition May 2008 / Subject to change maxon motor control 3