The performance of precision planters is very important for attaining uniform seed spacing. While a planter is on work, undesired situations such as spinning and slipping on ground wheel, vibration, seizing and jamming on the chain-sprocket systems may occur during the transfer of the motion from the ground wheel to the seed-metering unit especially at high operating speeds. In order to overcome these problems, it was aimed to develop an electro-mechanic drive system (EMDS) for seed metering units of a classic single seed planter. The performances of the EMDS and the classic drive system (CDS) were tested at three different operating speeds (v(f)) (5, 7.5, 10 km/h) and ten different seed spacing (z(t)) from 6 to 29.3 cm at laboratory. Both systems were compared regarding to the seed spacing uniformity. When the EMDS was used, the quality of feed index (I-qf), multiple index (I-mult), miss index (Hiss) and precision index (I-p,) were ranged as such: 2.91-95.36%, 0-1.73%, 4.45-97.09% and 8.79-22.14%, respectively. At the test of the CDS, the performance indices varied as such: Iqf 2.09-98.55%, I-mult 0-0.36% and I-miss 1.09-97.91%, I-p, 5.79-20.92%. Seed spacing uniformities were found as "good" and "moderate" for both systems. Average seed spacing values obtained from the EMDS were found to be closer to the theoretical seed spacing values compared with that obtained from the CDS. EMDS enabled the suggested optimum seeding rate, a quick and simple setting possibility, synchronize and real-time control, the ability to work under higher speeds, individual movement and control for each metering unit. However, EMDS should be tested to determine the success of the system in practice. Therefore, the field performance of EMDS with respect to plant spacing uniformity and operational parameters (variation among rows, fuel consumption and negative slippage) were examined in the following part of this study (Part II: Field Performance).