Method and device for simulating the mass of motor vehicles placed on stationary test stands

• US 6,516,287 B1
• Filed: 04/09/2001
• Issued: 02/04/2003
• Est. Priority Date: 10/09/1998
• Status: Expired due to Term

• Current Assignee: Schenk Pegasus GmbH
• Original Assignee: Schenk Pegasus GmbH
• Inventors: Freitag, Gernot
• Primary Examiner(s): SHAH, KAMINI S
• Application Number:
  US09/807,163
• Time in Patent Office: 666 Days
• Field of Search: 702/173, 702/174, 702/175, 701/29, 703/8, 731/16, 731/17, 738/620.9
• US Class Current: 702/173
• CPC Class Codes: G01M 17/0072 the wheels of the vehicle co-operating with rotatable rolls G01M17/022, G01M17/045, G01M17/065 take precedence

Abstract

The invention relates to a method and an apparatus for the mass simulation of vehicle masses on a stationary roller test stand, wherein the simulation mass (m_sim) is determined from the test stand mass (m_P) and from the mass (mRad h?) of the non-driven rotatable vehicle parts that are determined by measuring techniques, as well as from the mass (mRad h?) of the driven rotatable vehicle parts that are determined by measuring techniques, and with the aid of the translatory vehicle mass (m_F), in an evaluating device (10) of the test stand.

Claims

1. Method for the mass simulation of vehicle masses on stationary test stands, especially on vehicle roller test stands, whereby the simulation mass is determined from the vehicle masses rotating along on the test stand and the remaining vehicle masses, characterized in that a separate testing process is carried out on the test stand for the remaining rotatable vehicle parts, and the vehicle total mass (m_total), which serves for the determination of the simulation mass (m_V-sim), is determined from the measured values (m_wheel-F) of the separate testing process and with the aid of the translatory vehicle mass (m_V) as well as the vehicle masses (m_wheel-R) rotating along during the testing process.

2. Method for the mass simulation according to patent claim 1, characterized in that first the test stand mass (m_T) without a vehicle (5) is determined, and the rotatable vehicle masses (m_wheel-F) of the non-driven vehicle parts are measured in a separate test process, and in a further test process the vehicle masses (m_wheel-R) of the driven rotatable vehicle parts are measured, from which, with the aid of the prescribed translatory vehicle mass (m_V), the vehicle total mass (m_total) is determined.

3. Method for the mass simulation according to claim 1, characterized in that a driving resistance characteristic curve (DRC) is calculated for the vehicle (5) to be tested, from the determined vehicle total mass (m_total) and from the velocity variations (Δ

v) per time unit (Δ

t) determined in a roll-out test of the motor vehicle (5), whereby the simulation mass (m_V-sim) is determined with the aid of the driving resistance characteristic curve (DRC).

4. Method for the mass simulation according to claim 1, characterized in that a driving resistance characteristic curve (DRC), which was determined by means of estimated mass (m_estimated) of the non-accelerated rotatable vehicle parts, is set into a ratio with the measured mass (m_total) of the non-accelerated vehicle parts, and from that, corrected driving resistance values (F_DRC) or a corrected driving resistance characteristic curve (DRC) is determined, which serves for the determination of the simulation mass (m_V-sim).

5. Apparatus for carrying out the method according to claim 1, characterized in that the regulating circuit (9) of a stationary test stand contains an evaluating device (10) with a memory circuit (13), which are so embodied, so that in a testing process without vehicle loading, the test stand mass (m_T) or the test stand losses (F_lT) are determined by means of the evaluating device (10) and stored in the memory circuit (13), as well as in a further testing process the rotatable non-driven vehicle masses (m_wheel-F) and in a further separate testing process C the driven rotatable vehicle masses (m_wheel-R) are determined by means of a measuring process by the evaluating device (10) and stored in the memory circuit (13), and the vehicle total mass (m_total), which serves for the determination of the simulation mass (m_V-sim), is calculated with the aid of the translatory vehicle mass (m_V).

6. Apparatus according to claim 5, characterized in that the evaluating device (10) is connected with a test input device (11) into which the velocity values (Δ

v) per time (Δ

t) are input and therefrom the values for the braking (−

a) of the vehicle are calculated in connection with so-called roll-out tests of a vehicle (5) on the street, from which driving resistance characteristic values are formed by the evaluating device (10) with the aid of the measured vehicle masses (m_wheel-F, m_wheel-R), wherein the vehicle resistance characteristic values serve for the determination of the simulation mass (m_V-sim).

7. Apparatus according to claim 5, characterized in that values of a resistance characteristic curve (DRC) with estimated total mass values (m_estimated) are input into the evaluating device (10), and are set into a ratio with measured vehicle total mass values (m_total) in the evaluating device (10), from which the evaluating device (10) forms values (F_DRC) or a corrected driving resistance characteristic curve (DRC).

8. Apparatus according to claim 5, characterized in that the evaluating device (10), the memory circuit (13) and the test input device (11) are embodied as an electronic circuit.

9. Apparatus according to claim 5, characterized in that the evaluating device (10), the memory circuit (13) and/or the test input device (11) are embodied as a program controlled computer circuit.