The Fundamentals
Suction grippers use pneumatic vacuum to adhere to object surfaces. Parallel jaw grippers use two actuated fingers to pinch objects. Both approaches work reliably within their design envelope and fail in predictable ways outside it. The decision between them is almost entirely determined by the object set and task structure, not by gripper quality.
Performance Comparison
| Metric | Suction (e.g. Schmalz SAXO) | Parallel Jaw (e.g. Robotiq 2F-85) |
|---|---|---|
| Max picks/min (structured bin) | 600–1,200 | 200–600 |
| Max payload | 5–20 kg (surface-dependent) | 2–8 kg |
| Cycle time (approach to secured) | 0.3–0.8 s | 0.8–2.5 s |
| Contact points | 1 (distributed over cup) | 2 (point or line) |
| Approach direction flexibility | Top-down only | Any direction with proper finger |
| Cost (basic models) | $200–2,000 | $1,500–5,000 |
| Maintenance interval | Cup replacement 500K cycles | Finger pad replacement 1M cycles |
Object Compatibility
Suction works best with: flat or gently curved surfaces larger than the cup diameter (50-80mm minimum for standard cups), smooth non-porous materials (plastic bags, cardboard boxes, glass, metal panels), objects where top-down access is available, and high-volume structured environments where the same object type repeats.
Suction fails with: curved objects smaller than the cup (spheres, cylinders), porous materials (fabric, foam, unfinished wood), wet or oily surfaces, objects requiring approach from the side, and objects heavier than 5kg at full arm reach where seal integrity cannot be guaranteed.
Parallel jaw works best with: objects with at least two roughly parallel graspable faces, rigid items that will not deform under grip force, arbitrary approach angles, and objects too small or irregular for suction cups.
Parallel jaw fails with: perfectly spherical objects (require specialized finger geometry), very small parts under 8-10mm, extremely fragile items where contact pressure must be near zero, and high-speed structured sorting where suction's faster cycle time is critical.
Application Use Case Recommendations
| Application | Recommended Gripper | Reason |
|---|---|---|
| E-commerce fulfillment (boxes, pouches) | Suction | Speed, flat surfaces, consistent objects |
| Precision electronic assembly | Parallel jaw (custom fingers) | Controlled force, arbitrary approach |
| Food packaging (produce, meat) | Suction (food-grade cups) | No pinch damage, fast cycle |
| Small parts assembly (screws, connectors) | Parallel jaw | Sub-10mm objects require pinch |
| Retail shelf restocking (mixed SKUs) | Parallel jaw or adaptive | High object variety, suction inconsistent |
| Depalletizing uniform boxes | Suction (multi-cup) | High payload, fast cycle, flat surface |
Combined Approaches
For mixed-SKU environments (retail, e-commerce with irregular items), the most capable approach is a combination gripper: a pneumatic suction cup array for flat objects combined with one or two articulated fingers for irregular items. Several commercial options exist (Soft Robotics MPG, Festo DHEFB), and custom combined designs are feasible at the $3,000-8,000 range for most manipulation arms.
Implications for Robot Learning Data Collection
From a machine learning perspective, parallel jaw grippers produce richer training data for contact-rich manipulation learning. Each grasp involves two contact points with independent normals — this contact distribution contains more information about the object geometry and grasp strategy than a single suction seal. For teams training generalizable grasping policies, parallel jaw data is typically more valuable per demonstration.
Suction data is simpler to collect at high volume — fewer failed demonstrations, faster cycle time, less operator skill required. For applications where suction is the deployment end-effector (e-commerce, box picking), collect suction demonstrations. Do not collect parallel jaw data and hope to transfer to suction — the action distributions are incompatible.
Browse compatible grippers and end-effectors in the SVRC store.