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CIM Motor

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CIM (2.5 inch FR801-001)

Stall current (amps) 133.0
Stall torque (in-lb) 21.462
Max power output (watts) 337
Free speed (rpm) 5310

One of the two basic skid steer drive trains included in the kit of parts is designed to utilize one or two CIM motors on each side of the robot. This exact motor has been known over the years as the “CIM”, “Chiaphua”, or “Atwood” motor. The motor is provided in the kit of parts as part number “FR801-001”. Some years (2006 & 2007) have also shipped a larger three inch “Mini-bike” motor (part number FP801-005).

Exact specifications are available from FIRST: FR801-001 MOTOR SPECIFICATIONS

Torque and Efficiency curves

  Torque (oz-in) Speed (RPM) Current (A) Power (Wo) Efficiency
Free Load 0 5310 2.7 0 0%
Normal Load 64.0 4320 27 205 63%
Max Efficiency 45.0 4614 19.8 154 65%
Max Power 171.7 2655 67.9 337 41%
Stall 343.4 0 133.0 0 0%

Kit of Parts

2017

Four standard 2.5” motors are included, along with one miniCIM motor and one BAG motor. In FIRST Choice, CIM motors were available to veteran teams at a cost of 20 credits each, with no quantity limit.

2014-2016

Four standard 2.5” motors are included, along with one miniCIM motor and one BAG motor.

2013

Two standard 2.5” motors are included, along with one miniCIM motor and one BAG motor.

2012

Two standard 2.5” motors are included.

2011

Two standard 2.5” motors included, with AndyMark CIMple Box assembly. [1]

2008-2010

Two standard 2.5” motors are included, the 3” CIM is no longer legal.

2007

Two of the standard 2.5” motors are included, and a larger 3” CIM (previously labeled as mini-bike motors).

2006

Two of the four 2.5” CIM motors were replaced with two larger 3” “mini-bike” motors (labeled as ‘Motor (Large)’ in the KOP list). [2]

2005

Four standard 2.5” motors are included in the KOP.

2003-2004

Two standard 2.5” motors are included in the KOP, now labeled as CIM Motors in the KOP list.

2002

CIM motors make their debut in FRC. Two 2.5” motors are provided in the KOP, labeled as Chiaphua Motors in the KOP list.

Usage Notes

  • Partially because of the CIM’s relatively large size and consequentially low power density, the motor can withstand longer periods at, or near, stall. CIM do not burn out nearly as often as a drill motor or a fisher price motor.
  • Because the CIM is not designed for a specific application like the (obsolete) drill motor, it has little or no wiring bias. This means the motor is equally powerful in forward in reverse. This can be useful in many applications. For example, drive trains which involve a pair of motors running in opposite directions can suffer from driving in a large radius circle when both motors are set to equal speeds. The CIM is relatively immune from such problems in that situation.