Exhibit 10.15

Silicon Valley Bank

Amendment to Loan Documents

|Borrower: |  | Allied Motion Technologies Inc. (fka Hathaway Corporation)
Allied Motion Systems Corporation (fka Hathaway Systems Corporation)
Allied Motion Process Instrumentation Corporation (fka Hathaway Process Instrumentation Corporation)
Allied Motion Control Corporation (fka Hathaway Motion Control Corporation)
Allied Motion Industrial Automation, Inc. (fka Hathaway Industrial Automation, Inc.)
Computer Optical Products, Inc.
EMOTEQ Corporation
Motor Products-Ohio Corporation
Motor Products Corporation (fka Motor Products-Owosso Corporation)
|--------- |  | -----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
|Date:     |  | September 26, 2003                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         

THIS AMENDMENT TO LOAN DOCUMENTSis entered into between SILICON VALLEY BANK ("Silicon") and the borrower named above (jointly and
severally, "Borrower").

The
Parties agree to amend the Loan and Security Agreement between them, dated May 7, 1998 (as amended from time to time, the "Loan Agreement"), as follows, effective as of
September 10, 2003. (Capitalized terms used but not defined in this Amendment shall have the meanings set forth in the Loan Agreement.)

1.     Modified Interest Rate.Section 2 of the Schedule to Loan and Security Agreement, entitled "2. INTEREST," is hereby
amended to read as follows:



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2.     Modified Collateral Monitoring Fee.The Collateral Monitoring Fee set forth in Section 3 of the Schedule to Loan
and Security Agreement is hereby amended to read as follows:



3.     Modified Maturity Date.Section 4 of the Schedule to Loan and Security Agreement is hereby amended to read as
follows:



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4.     Fee.In consideration for Silicon entering into this Amendment, Borrower shall concurrently pay Silicon a fee in the
amount of $6,250, which shall be non-refundable and in addition to all interest and other fees payable to Silicon under the Loan Documents. Silicon is authorized to charge said fee to
Borrower's loan account.

5.     Representations True.Borrower represents and warrants to Silicon that all representations and warranties set forth in the
Loan Agreement, as amended hereby, are true and correct.

6.     General Provisions.This Amendment, the Loan Agreement, any prior written amendments to the Loan Agreement signed by
Silicon and Borrower, and the other written documents and agreements between Silicon and Borrower set forth in full all of the representations and agreements of the parties with respect to the subject
matter hereof and supersede all prior discussions, representations, agreements and understandings between the parties with respect to the subject hereof. Except as herein expressly amended, all of the
terms and provisions of the Loan Agreement, and all other documents and agreements between Silicon and Borrower shall continue in full force and effect and the same are hereby ratified and confirmed.

|Borrower:                                                  |  | Silicon:                                          
|---------------------------------------------------------- |  | --------------------------------------------------
|ALLIED MOTION TECHNOLOGIES INC. (fka Hathaway Corporation) |  | SILICON VALLEY BANK                               
|By                                                         |  | /s/RICHARD D. SMITHPresident or Vice President    
|                                                           |  |                                                   
|By                                                         |  | /s/SUSAN M. CHIARMONTESecretary or Ass't Secretary
|                                                           |  |                                                   

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|Borrower:                                                                   |  | Borrower:                                                                                           
|--------------------------------------------------------------------------- |  | ----------------------------------------------------------------------------------------------------
|ALLIED MOTION SYSTEMS CORPORATION (fka Hathaway Systems Corporation)        |  | ALLIED MOTION PROCESS INSTRUMENTATION CORPORATION (fka Hathaway Process Instrumentation Corporation)
|By                                                                          |  | /s/RICHARD D. SMITHPresident or Vice President                                                      
|By                                                                          |  | /s/SUSAN M. CHIARMONTESecretary or Ass't Secretary                                                  
|Borrower:                                                                   |  | Borrower:                                                                                           
|ALLIED MOTION CONTROL CORPORATION (fka Hathaway Motion Control Corporation) |  | ALLIED MOTION INDUSTRIAL AUTOMATION, INC. (fka Hathaway Industrial Automation, Inc.)                
|By                                                                          |  | /s/RICHARD D. SMITHPresident or Vice President                                                      
|By                                                                          |  | /s/SUSAN M. CHIARMONTESecretary or Ass't Secretary                                                  
|Borrower:                                                                   |  | Borrower:                                                                                           
|COMPUTER OPTICAL PRODUCTS, INC.                                             |  | EMOTEQ CORPORATION                                                                                  
|By                                                                          |  | /s/RICHARD D. SMITHPresident or Vice President                                                      
|By                                                                          |  | /s/SUSAN M. CHIARMONTESecretary or Ass't Secretary                                                  
|Borrower:                                                                   |  | Borrower:                                                                                           
|MOTOR PRODUCTSOHIO CORPORATION                                             |  | MOTOR PRODUCTS CORPORATION (fka Motor Products-Owosso Corporation)                                  
|By                                                                          |  | /s/RICHARD D. SMITHPresident or Vice President                                                      
|By                                                                          |  | /s/SUSAN M. CHIARMONTESecretary or Ass't Secretary                                                  

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GUARANTOR'S CONSENT

The undersigned acknowledges that his consent to the foregoing Agreement is not required, but the undersigned nevertheless does hereby consent to the foregoing
Agreement and to the documents and agreements referred to therein and to all future modifications and amendments thereto, and any termination thereof, and to any and all other present and future
documents and agreements between or among the foregoing parties. Nothing herein shall in any way limit any of the terms or provisions of the Continuing Guaranty of the undersigned, all of which are
hereby ratified and affirmed.

|Guarantor:                                                                                           |  | Guarantor:                                                                 
|---------------------------------------------------------------------------------------------------- |  | ---------------------------------------------------------------------------
|ALLIED MOTION TECHNOLOGIES INC. (fka Hathaway Corporation)                                           |  | ALLIED MOTION SYSTEMS CORPORATION (fka Hathaway Systems Corporation)       
|By                                                                                                   |  | /s/RICHARD D. SMITHPresident or Vice President                             
|By                                                                                                   |  | /s/SUSAN M. CHIARMONTESecretary or Ass't Secretary                         
|Guarantor:                                                                                           |  | Guarantor:                                                                 
|ALLIED MOTION PROCESS INSTRUMENTATION CORPORATION (fka Hathaway Process Instrumentation Corporation) |  | ALLIED MOTION CONTROL CORPORATION (fka Hathaway Motion Control Corporation)
|By                                                                                                   |  | /s/RICHARD D. SMITHPresident or Vice President                             
|By                                                                                                   |  | /s/SUSAN M. CHIARMONTESecretary or Ass't Secretary                         
|Guarantor:                                                                                           |  | Guarantor:                                                                 
|ALLIED MOTION INDUSTRIAL AUTOMATION, INC. (fka Hathaway Industrial Automation, Inc.)                 |  | COMPUTER OPTICAL PRODUCTS, INC.                                            
|By                                                                                                   |  | /s/RICHARD D. SMITHPresident or Vice President                             
|By                                                                                                   |  | /s/SUSAN M. CHIARMONTESecretary or Ass't Secretary                         
|                                                                                                     |  |                                                                            

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|Guarantor:                                                         |  | Guarantor:                                        
|------------------------------------------------------------------ |  | --------------------------------------------------
|EMOTEQ CORPORATION                                                 |  | MOTOR PRODUCTSOHIO CORPORATION                   
|By                                                                 |  | /s/SUSAN M. CHIARMONTESecretary or Ass't Secretary
|Guarantor:                                                         |  |                                                   
|MOTOR PRODUCTS CORPORATION (fka Motor Products-Owosso Corporation) |  |                                                   
|By                                                                 |  | /s/RICHARD D. SMITHPresident or Vice President    
|By                                                                 |  | /s/SUSAN M. CHIARMONTESecretary or Ass't Secretary

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