Trans­mis­sion test bench with Lab­View and Bosch-Rexroth servos

Test bench up to 15000 Nm

The com­pa­ny Schmahl pro­duces gears for con­struc­tion equip­ment that has to be pro­duced exact­ly due to spe­cial demands. In order to avoid pro­duc­tion- and mate­r­i­al defects a test bench was devel­oped in coop­er­a­tion between the com­pa­nies Schmahl, Bosch Rexroth and Qual­i­ty Automa­tion on which you let up to 15000 Nm sink in. The test bench is con­struct­ed in that way, that the dri­ve and the out­puts of elec­tri­cal motors are simulated.

Dri­ve and adjust­ment con­trol with the MLD of Bosch Rexroth

The MLD of Bosch Rexroth dri­ves and con­trols the motors, in doing so it serves also as SPS and con­trols e.g. the hydraulic sys­tem and gath­ers mea­sur­ing val­ues via ana­logue inputs. The pow­er ele­ment of the IndraDrive series con­sists of a sup­ply unit, two inter­me­di­ate cir­cle resis­tors and con­trol equip­ment for each motor. The capac­i­ty of the sup­ply unit comes to 120 KW, the motors have a nom­i­nal load of in total 141 KW. The MLD as cen­tral dri­ve and con­trol equip­ment is con­nect­ed with the con­trol units, the I/Os und the ana­logue units via Ser­cos Bus.

TCP con­nects the systems

The test bench is visu­al­ized by a Lab­View appli­ca­tion that com­mu­ni­cates with the MLD via TCP/IP. The motors and all con­trol com­po­nents can be con­trolled sep­a­rate­ly dur­ing the ser­vice oper­a­tion. A test cycle is pre­pared with this appli­ca­tion and saved in a data bank. This is pro­vid­ed in that way that the con­trol pro­grams are put in by the qual­i­ty assur­ance and that the sin­gle gears can be test­ed by the oper­a­tor via an order admin­is­tra­tion. The data of the test cycle con­tain dri­ving speed, full load as well as tem­per­a­ture, dis­tance mea­sure­ment and an impact sound mea­sure­ment. These data can be saved in the data bank in a cycle of 10ms.

All from one source

The project was realised exclu­sive­ly by Qual­i­ty Automa­tion except the mechan­i­cal works. It includes the elec­tri­cal con­struc­tion, the con­struc­tion of switch­board cab­i­nets, the soft­ware for the MLD and the Lab­View application.