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Many thanks to all those who responded to my torque motor request.
I now post an unedited copy of the information for any other interested
readers.
Regards
Andy Cresswell
andrew.cresswell@neuro.ki.se
*****************************************
Cambridge Technology
23 Elm St
Watertown, MA 02172
U.S.A.
(617) 923-1181
They manufacture a number of different torque motors and controllers. The
controllers we use can switch between load and position control "on the fly"
I believe they have torque capacities through at least 5 Nm, and may go
higher. The motors can be a bit particular: we send them back about once
every year or two for recalibration.
*****************************************
We buy torque motors for our test equipment from Grainger. They sell a wide
range of DC and AC type motors which may satisfy your needs. From your
description you will need to design and build a mechanical linkage and a control
system to do exactly what you want. Our area Grainger office is at 603-668-7161.
However, MTS may have a product colse enough to your needs. You may wish to
contact them in the US. MTS 919-677-1610 919-677-2480fax
*****************************************
I recommend the NSK (Nippon Seiko) Megatorque RS0604 direct drive DC brushless
servo-motor. It has an internal resolver to provide position and velocity
feedback, and can be controlled by postion/velocity/torque commands. This
motor is capable of up to 15 N-m torque. Larger and smaller versions are
available.
We have used these motors extensively in our robotics research and find
them to be simple to interface and mechanically very reliable. Unfortunately
they are somewhat expensive.
*****************************************
The Gait Laboratory at the Hugh MacMillan Rehabilitation Centre in Toronto has
an "Ankle Actuator" that will dorsiflex the ankle joint at a specified angular
velocity, while recording the angular velocity and the resistive torque about
the ankle. It is used to quick stretch the ankle plantarflexors in children
with spasticity, while recording the EMG response to the stretch. For
information, contact:
Dr. Stephen Naumann,
Rehabilitation Engineering Dept.,
Hugh MacMillan Rehabilitation Centre,
350 Rumsey Rd.,
Toronto, Ontario
Canada, M4G 1R8.
Phone: (416) 425-6220
*****************************************
You might want to look into a stepping motor like the ones that are used on
CNC milling machines. A local machine shop may be able to put you in
contact with a manufacturer.
*****************************************
We are currently building a system similar to a Cybex or Biodex but
with much better control, measurement accuracy, and torque response.
It is specifically for research purposes. I saw an amazing
demonstration of a motor and controller which we subsequently
purchased for the project. It has extremely fast response in either
direction, maintains 100% of torque even when stopped, and is
relatively easy to control via computer. The controller is the key.
It is called MICROVECTOR and is distributed by a New Zealand firm so
maybe you should fly out for a personal visit
PDL Electronics Ltd
PO Box 741
Napier NZ
*****************************************
You should look up a professor at Drexel University,
Philadelphia, USA. He has done a good deal of experiments with an
apparatus which may do some of the things you are looking for. He has
tested ankle resistance to movement in different directions and with
different footwear. I understand that he applies torque along one of the
three axes and measures the movement.
I am sorry I can't give you his name right now. He presented at
the Footwear Symposium at the 1994 Canadian Society of Biomechanics
Meeting in Calgary
*****************************************
I know of only one commercial manufacturer
of torque motors with servo controllers
for position and force feedback control.
Try Cambridge Technology Inc.
23 Elm St.
Watertown MA 02172 USA
Tel (617) 923-1181
FAX (617) 924-8378
However, they may not make a large-enough
motor for your application.
*****************************************
See the book Muscles, masses and motion by Geoffrey Walsh. He has built many
torque motors over the years, the book may give you some hints.
*****************************************
Try the motors made by Aerotech, Inc. They have a response time on the
order of 10 ms. We have used them to test mouse ankle muscles
(see my paper in J. Appl. Physiology a couple of years ago). But we have
used a much large motor to test human ankle muscles very successfully
once we had put a 5:1 ratio on it using a pulley + pulley plus tensioned steel band to drive the pulley with minimal compliance. The address for Aerotech
is listed in the JAP paper. To control the motor we used a Mektronix MC1
motor controller board. We also wrote custom C++ code.
*****************************************
Andrew.Cresswell@neuro.ki.se
I now post an unedited copy of the information for any other interested
readers.
Regards
Andy Cresswell
andrew.cresswell@neuro.ki.se
*****************************************
Cambridge Technology
23 Elm St
Watertown, MA 02172
U.S.A.
(617) 923-1181
They manufacture a number of different torque motors and controllers. The
controllers we use can switch between load and position control "on the fly"
I believe they have torque capacities through at least 5 Nm, and may go
higher. The motors can be a bit particular: we send them back about once
every year or two for recalibration.
*****************************************
We buy torque motors for our test equipment from Grainger. They sell a wide
range of DC and AC type motors which may satisfy your needs. From your
description you will need to design and build a mechanical linkage and a control
system to do exactly what you want. Our area Grainger office is at 603-668-7161.
However, MTS may have a product colse enough to your needs. You may wish to
contact them in the US. MTS 919-677-1610 919-677-2480fax
*****************************************
I recommend the NSK (Nippon Seiko) Megatorque RS0604 direct drive DC brushless
servo-motor. It has an internal resolver to provide position and velocity
feedback, and can be controlled by postion/velocity/torque commands. This
motor is capable of up to 15 N-m torque. Larger and smaller versions are
available.
We have used these motors extensively in our robotics research and find
them to be simple to interface and mechanically very reliable. Unfortunately
they are somewhat expensive.
*****************************************
The Gait Laboratory at the Hugh MacMillan Rehabilitation Centre in Toronto has
an "Ankle Actuator" that will dorsiflex the ankle joint at a specified angular
velocity, while recording the angular velocity and the resistive torque about
the ankle. It is used to quick stretch the ankle plantarflexors in children
with spasticity, while recording the EMG response to the stretch. For
information, contact:
Dr. Stephen Naumann,
Rehabilitation Engineering Dept.,
Hugh MacMillan Rehabilitation Centre,
350 Rumsey Rd.,
Toronto, Ontario
Canada, M4G 1R8.
Phone: (416) 425-6220
*****************************************
You might want to look into a stepping motor like the ones that are used on
CNC milling machines. A local machine shop may be able to put you in
contact with a manufacturer.
*****************************************
We are currently building a system similar to a Cybex or Biodex but
with much better control, measurement accuracy, and torque response.
It is specifically for research purposes. I saw an amazing
demonstration of a motor and controller which we subsequently
purchased for the project. It has extremely fast response in either
direction, maintains 100% of torque even when stopped, and is
relatively easy to control via computer. The controller is the key.
It is called MICROVECTOR and is distributed by a New Zealand firm so
maybe you should fly out for a personal visit
PDL Electronics Ltd
PO Box 741
Napier NZ
*****************************************
You should look up a professor at Drexel University,
Philadelphia, USA. He has done a good deal of experiments with an
apparatus which may do some of the things you are looking for. He has
tested ankle resistance to movement in different directions and with
different footwear. I understand that he applies torque along one of the
three axes and measures the movement.
I am sorry I can't give you his name right now. He presented at
the Footwear Symposium at the 1994 Canadian Society of Biomechanics
Meeting in Calgary
*****************************************
I know of only one commercial manufacturer
of torque motors with servo controllers
for position and force feedback control.
Try Cambridge Technology Inc.
23 Elm St.
Watertown MA 02172 USA
Tel (617) 923-1181
FAX (617) 924-8378
However, they may not make a large-enough
motor for your application.
*****************************************
See the book Muscles, masses and motion by Geoffrey Walsh. He has built many
torque motors over the years, the book may give you some hints.
*****************************************
Try the motors made by Aerotech, Inc. They have a response time on the
order of 10 ms. We have used them to test mouse ankle muscles
(see my paper in J. Appl. Physiology a couple of years ago). But we have
used a much large motor to test human ankle muscles very successfully
once we had put a 5:1 ratio on it using a pulley + pulley plus tensioned steel band to drive the pulley with minimal compliance. The address for Aerotech
is listed in the JAP paper. To control the motor we used a Mektronix MC1
motor controller board. We also wrote custom C++ code.
*****************************************
Andrew.Cresswell@neuro.ki.se